Geochronological and Geochemical Constraints on the Lithospheric Evolution of the Arabian Shield, Saudi Arabia: Understanding Plutonic Rock Petrogenesis in an Accretionary Orogen.
A thesis submitted for the degree of Doctor of Philosophy
Frank Alexander Robinson B.Sc. (Hons)
Department of Geology and Geophysics The University of Adelaide February 2014 Table of Contents
Abstract vi Declaration viii Acknowledgments ix List of Figures x List of Tables xv
Chapter 1: General Introduction 1 1.1 Granite Overview 1 1.2 Development of the A-type Classification 1 1.3 A-type Characteristics and Global Occurrences 2 1.4 Anorogenic Timing and Tectonic Significance 3 1.5 Petrogenetic Models for Generating Anorogenic Magmatism 4 1.6 The East African Orogen and its Relation to the Arabian-Nubian Shield 5 1.7 Arabian Shield Geological Overview 7 1.8 Aims 14
Chapter 2: Petrographic Constraints on Sampled Arabian Shield Plutons; Subdivision of A-type Suites 15 2.1 Introduction 15 2.2 Sample Selection 16 2.2.1 Adopted Classification Nomenclature 18 2.3 Granitoid Petrography 19 2.3.1 Makkah Suite (dm) 20 2.3.2 Shufayyah Complex (su) 23 2.3.3 Kawr Suite (kw) 25 2.3.4 Abanat Suite (aa) 31 2.3.5 Malik Granite (kg) 33 2.4 Petrography Summary and Discussion 35
Chapter 3: Arabian Shield Pluton Geochronology; Subtle Changes in a Homogeneous Juvenile Mantle 40 3.1 Introduction 40
i 3.2 U-Pb Geochronology 41 3.2.1a Makkah Suite (dm): Gabbro-Diorite 41 3.2.1b Shufayyah Complex (su): Tonalite 43 3.2.1c Jar-Salajah Complex and Fara’ Trondhjemite (js): Granodiorite 46 3.2.1d Subh Suite (sf): Rhyolite 48 3.2.1e Kawr Suite (kw): Granodiorite 50 3.2.1f Al Hafoor Suite (ao): Alkali-Granite 53 3.2.1g Najirah Granite (nr): Granite 55 3.2.1h Wadbah Suite (wb): Alkali-Granite 57 3.2.1i Ibn Hashbal Suite (ih): Alkali-Granite 59 3.2.1j Ar Ruwaydah Suite (ku): Granite 61 3.2.1k Haml Suite (hla): Quartz-Monzonite 63 3.2.1l Kawr Suite (kw): Alkali-Granite 65 3.2.1m Idah Suite (id): Alkali-Granite 67 3.2.1n Al Khushaymiyah Suite (ky): Quartz-Monzonite 70 3.2.1o Malik Granite (kg): Granite 72 3.2.1p Admar Suite (ad): Syenite 74 3.2.1q Al Bad Granite Super Suite (abg): Alkali-Granite 76 3.2.1r Al Hawiyah Suite (hwg): Granite 78 3.2.1s Mardabah Complex (mr): Syenite 81 3.2.2 Arabian Shield U-Pb Geochronology Summary and Discussion 83 3.3 Hafnium (Hf) Isotopes 88 3.3.1 Western Shield 90 3.3.2 Eastern Shield 90 3.3.3 Nabitah Orogenic Belt 93 3.3.4 Hafnium Isotope Summary 95
Chapter 4: Geochemical Constraints on Arabian Shield Plutonic Rocks 97 4.1 Introduction 97 4.2 Whole Rock Major and Trace Element Geochemistry 98 4.2.1 Island Arc and Syncollisional Granitoids (IA+Syn) 99 4.2.2 Nabitah and Halaban Suture Granitoids (NHSG) 104 4.2.3 Post-Orogenic Perthitic Granitoids (POPG) 111 4.2.4 Anorogenic Aegirine Perthitic Granitoids (AAPG) 119
ii 4.3 Whole Rock Isotope Geochemistry 125 4.3.1 Island Arc and Syncollisional Granitoids (IA+Syn) 126 4.3.2 Nabitah and Halaban Suture Granitoids (NHSG) 129 4.3.3 Post-Orogenic Perthitic Granitoids (POPG) 134 4.3.4 Anorogenic Aegirine Perthitic Granitoids (AAPG) 137 4.3.5 Shield Volcanics 139 4.3.6 Isotope Geochemistry Summary 142 4.4 Arabian Shield Granitoid Classification/Tectonic Discrimination 143 4.4.1 Post-Orogenic Perthitic Granitoids (POPG) and Anorogenic Aegirine Perthitic Granitoids (AAPG) 143 4.4.2 Island Arc and Syncollisional Granitoids (IA+Syn) and Nabitah and Halaban Suture Granitoids (NHSG) 148 4.4.3 Western Shield and Nabitah Suture Mafic Endmembers 154 4.4.4 Geochemistry Summary and Discussion 157 4.4.4a Subdivision of Arabian Shield A-type Granitoids 159 4.4.4b Differentiating Contaminated and Enriched Mantle 163
Chapter 5: Insights into Mantle Source from Zircon Geochemistry 167 5.1 Introduction 167 5.2 Island Arc and Syncollisional Granitoids (IA+Syn) 168 5.2.1 Major Element Geochemistry 169 5.2.2 Trace Element Geochemistry 170 5.3 Nabitah and Halaban Suture Granitoids (NHSG) 175 5.3.1 Major Element Geochemistry 178 5.3.2 Trace Element Geochemistry 180 5.4 Post-Orogenic Perthitic Granitoids (POPG) 186 5.4.1 Major Element Geochemistry 186 5.4.2 Trace Element Geochemistry 187 5.5 Anorogenic Aegirine Perthitic Granitoids (WPG) 189 5.5.1 Major Element Geochemistry 190 5.5.2 Trace Element Geochemistry 191 5.6 Zircon Geochemistry Summary 193
iii Chapter 6: Discrete Crystallisation Ages within Granitoid Zircon Populations 195 6.1 Introduction 195 6.2 Identification of Distinguished Zircon Morphologies 196 6.3 Identification of Non-Gaussian Probability Distributions 200 6.4 Discrete Ages Using Isoplot Software 203 6.5 Establishment of Three Discrete Zircon Ages 204 6.6 Relationships between Machine Error and Age Separation 207 6.7 Additional Evidence for Discrete Ages and Discussion 214
Chapter 7: Arabian Shield Post-Orogenic and Anorogenic Granitoids; Petrogenetic Mechanisms for Distinct Contaminated and Enriched Mantle Sources 216 7.1 Introduction 216 7.2 Geochemical Characteristics of Contaminated Granitoids 217 7.3 Magmatic Pulsing in a Contaminated MASH Zone 222 7.4 Subtle Differences in Primitive Syenites; Two Mantle Sources 228 7.5 Enriched Mantle Within Plate Granitoids; Key to Economic Deposits 233 7.6 Within Plate Granitoids; Products of Lithospheric Delamination 236 7.7 Generation of Crustal Melts 238
Chapter 8: A Tectonic Synthesis of the Arabian Shield; Implications for Gondwana Assembly 241 8.1 Geochronological Overview 241 8.2 Island Arc Magmatism (950-750Ma) 243 8.3 Syncollisional Magmatism (730-636Ma) 250 8.4 Post-Orogenic Magmatism (636-600Ma) 251 8.5 Anorogenic Magmatism (<600Ma) 258 8.6 Evidence for Final Gondwana Assembly 265 8.7 Subtle Changes in Homogenous Juvenile Mantle Melts 270 8.8 Concluding Remarks 277
References 280
iv Appendices Appendix a Analytical Techniques 290 Appendix 1 Sample Catalogue from the Arabian Shield 303 1.1 Midyan Terrane 303 1.2 Jiddah Terrane 303 1.3 Hijaz Terrane 308 1.4 Ha’il Terrane 320 1.5 Ad Dawadimi Terrane 324 1.6 Tathlith Terrane 333 1.7 Afif Terrane 337 1.8 Asir Terrane 342 Appendix 2 Zircon U-Pb Geochronological Data 353 Appendix 3 Zircon Cathodoluminescence Images 396 Appendix 4 Zircon Hafnium Isotope Data 420 Appendix 5 Whole Rock Major and Trace Element Data; Ferrous Iron Determination 444 Appendix 6 Whole Rock Sm-Nd and Sr Isotope Data 468 Appendix 7 Zircon Rare Earth Element Geochemistry 477
v Abstract
The Arabian-Nubian shield reflects the complex interplay between juvenile oceanic and continental arc fragments accreted during the final stages of Gondwanian super continental assembly. To date, much of the geochronological and geochemical data from the Arabian Shield, Saudi Arabia, is absent or poorly constrained and extrapolated from neighbouring Middle Eastern and African countries. Little attention has been paid to the petrogenesis and tectonic significance of the plutonic rocks pursuant to lithospheric orogenesis.
A total of 137 samples from 26 geological units were collected from the Midyan, Hijaz, Asir, Tathlith, Afif, Ad Dawadimi and Ha’il terranes with particular emphasis on accretionary suture zone and within plate setting relationships. Extensive data bases are constructed using zircon U-Pb geochronology and Hf isotopes to evaluate Gondwanian significance and whole rock major and trace element geochemistry, Nd, Sm, Sr isotopes and zircon geochemistry to determine their petrogenetic properties. These parameters provide new insight into changing mantle conditions beneath collisional sutures (Yanbu, Nabitah and Halaban) and within plate asthenospheric upwelling.
19 granitic units are subdivided into metaluminous, peraluminous and peralkaline groups that possess distinguished island arc (~950-730Ma), syncollisional (~<730-636Ma), post tectonic (~<636-600Ma) and anorogenic (<600Ma) U-Pb geochronology. These magmatic phases represent accretionary cycles initiating from the dismantlement of Rodinia, closure of the Mozambique Ocean and final Gondwana amalgamation. Evidence for final assembly is recorded at ~525Ma (Najd fault reactivation) which is now the youngest dated magmatism in the Arabian-Nubian Shield and warrants repositioning of the regional unconformity at ~542Ma.
Emplacement of sampled Arabian Shield classic A-type post-tectonic and anorogenic granitoids falls into three categories: 1) Intrude sutures immediately following collision which contain extensive mafic cumulate fractionation and N-MORB affiliation. 2) Plate boundary juxtaposed suites without obvious mafic cumulates, but
vi posses contaminated N-MORB geochemistry. 3) Within plate granitoids isolated from plate boundaries and also without obvious mafic cumulates, but with a distinctive enriched (OIB) like asthenospheric mantle source. All categories produce similar felsic endmembers, but contain isotopically distinct mantle source. These are differentiated using a newly developed geochemical scheme (contaminated and enriched mantle granitoids) that is successfully applied to regional Arabian-Nubian examples.
The diachronous Nabitah Orogenic Belt symbolises collision and subduction between western oceanic and eastern continental terranes that was terminated by the appearance of category 1 post-tectonic granitoids. This long lived (~50Ma) granitic magmatism contains mingling textures, discrete crystallisation ages, distinguished zircon morphologies and isotopically less juvenile mafics that geochronologically and geochemically reflect magmatic pulsing from a contaminated lower crustal MASH zone. The transition from N-MORB like mafics to isotopically enriched granitoids (isotopically similar to category 3 suites) reflects subduction magmatism followed by slab tear and asthenospheric influx.
Conversely, the appearance of category 3 anorogenic plutons is characterised by widespread, tightly constrained (<10Ma) magmatism that is geochemically enriched, economic and symbolic of lithospheric delamination and asthenospheric (OIB like) upwelling. Differences between category 1, 2 and 3 zircon geochemistry constrain further contaminated and enriched mantle source behaviour that produces similar felsic products from distinguished petrogenetic processes.
In summary, the work presented in this thesis establishes clear distinctions between accretionary syncollisional suites and anorogenic suites, but more significantly, post-orogenic plutons confined to suture zones from those confined to within plate settings. This allows new petrogenetic insights into changing juvenile mantle beneath the Arabian Shield.
vii Declaration
I certify that this work contains no material which has been accepted for the award of any other degree or diploma in any university or other tertiary institution in my name and, to the best of my knowledge and belief, contains no material previously published or written by another person, except where due reference has been made in the text. In addition, I certify that no part of this work will, in the future, be used in a submission in my name, for any other degree or diploma in any university or other tertiary institution without the prior approval of the University of Adelaide and where applicable, any partner institution responsible for the joint-award of this degree.
I give consent to this copy of my thesis, when deposited in the University Library, being made available for loan and photocopying, subject to the provisions of the Copyright Act 1968.
I also give permission for the digital version of my thesis to be made available on the web, via the University’s digital research repository, the Library catalogue and also through web search engines, unless permission has been granted by the University to restrict access for a period of time
………………………….. Frank Alexander Robinson
…………………………..
viii Acknowledgements
Firstly, I would like to throw out a big thank you to my supervisors Professor John Foden and Associate Professor Alan Collins for their endless support, knowledge and enthusiasm throughout this project. I appreciate them allowing me the freedom to determine the direction of my thesis.
A special thank you must be awarded to the Saudi Arabian Geological Survey for providing me with the opportunity and support to carry out this project. In particular, Khalid Kadi, Mubarak Al-Nahdi, Fayek Kattan and Abdullah Yazidi must be thanked for their gracious hospitality and support in Saudi Arabia. Their ongoing friendship has been invaluable for the completion of this project.
This project would not have been possible without the tireless efforts of the technical support staff from Adelaide Microscopy. Ben Wade, Angus Netting and Aoife McFadden must be recognised for their help and support in obtaining geochronological and geochemical data. David Bruce and John Stanley from the Adelaide Geology Department must also take the stage for their help and advice in obtaining geochemical data. Dr Justin Payne has also provided invaluable help and support throughout this project. Paolo Sossi must also be thanked for his help with whole rock wet chemistry and iron determination.
To the many geology friends I have made along the way, in particular Ben Vanderhoek, Russell Smits, Jade Anderson and Alec Walsh, I thank you all for the much needed coffees and lunches we had together. Without these I probably would not have made it through to the end. I would like to thank my family, especially my mother and father for putting up with my various moods and coaching me through to submission. Max and Zen must also be thanked for keeping me sane by baking brownies and letting me win at Catan. Finally, a big thanks to all my brothers and sisters, but in particular that big lug Tony for keeping things light hearted all the way to the end.
ix List of Figures
Chapter 1 1 Figure 1.1: The Arabian-Nubian Shield in relation to the Middle East and Africa 6 Figure 1.2: Arabian Shield Cryogenian (850-700Ma) intrusives. 9 Figure 1.3: Arabian Shield Cryogenian-Ediacaran (700-635Ma) intrusives 10 Figure 1.4: Arabian Shield Ediacaran (600-542Ma) intrusives 12 Figure 1.5: Arabian Shield unassigned Neoproterozoic intrusives 13
Chapter 2 15 Figure 2.1: Geological units sampled in the Arabian Shield 17 Figure 2.2: Makkah Suite field and petrographic photography 21 Figure 2.3: Makkah Suite plutonic classification 22 Figure 2.4: Shufayyah Complex field and petrographic photography and plutonic classification 24 Figure 2.5: Kawr Suite plutonic classification 26 Figure 2.6: Kawr Suite field and petrographic photography 27 Figure 2.7: Kawr Suite field and petrographic photography 30 Figure 2.8: Abanat Suite field and petrographic photography and plutonic classification 32 Figure 2.9: Malik Granite field and petrographic photography and plutonic classification 34 Figure 2.10: A summary map of all granitoid petrography 36 Figure 2.11: A plutonic classification summary diagram for all units sampled 37
Chapter 3 40 Figure 3.1: Makkah Suite U-Pb concordia 42 Figure 3.2: Shufayyah Complex U-Pb concordia 45 Figure 3.3: Jar-Salajah Complex U-Pb concordia 47 Figure 3.4: Subh Suite U-Pb concordia 49 Figure 3.5: Kawr Suite U-Pb concordia (sample kw42) 51 Figure 3.6: Al Hafoor Suite U-Pb concordia 54 Figure 3.7: Najirah Granite U-Pb concordia 56 Figure 3.8: Wadbah Suite U-Pb concordia 58
x Figure 3.9: Ibn Hashbal Suite U-Pb concordia 60 Figure 3.10: Ar Ruwaydah Suite U-Pb concordia 62 Figure 3.11: Haml Suite U-Pb concordia 64 Figure 3.12: Kawr Suite U-Pb concordia (sample kw51p) 66 Figure 3.13: Idah Suite U-Pb concordia 68 Figure 3.14: Al Khushaymiyah U-Pb concordia 71 Figure 3.15: Malik Granite U-Pb concordia 73 Figure 3.16: Admar Suite U-Pb concordia 75 Figure 3.17: Al Bad Granite Super Suite U-Pb concordia 77 Figure 3.18: Al Hawiyah Suite U-Pb concordia 79 Figure 3.19: Mardabah Complex U-Pb concordia 82 Figure 3.20: A summary of the U-Pb concordia for 452 zircons analysed 83 Figure 3.21: A summary probability diagram for 452 zircons analysed 85 Figure 3.22: Calculated ɛHf vs. U-Pb age (all Shield suites) 89 Figure 3.23: Calculated ɛHf vs. U-Pb age: IA and Syn suites part1 91 Figure 3.23: Calculated ɛHf vs. U-Pb age: PO and A suites part2 92 Figure 3.24: Calculated ɛHf vs. U-Pb age: Arabian Shield and southern India 94
Chapter 4 97
Figure 4.1: Hawker diagrams part1: SiO2 vs. MgO and Na2O+K2O 100
Figure 4.1: Hawker diagrams part2: SiO2 vs. FeO and K2O vs. Na2O 102 Figure 4.2: Hawker diagrams part1: SiO2 vs. Zr/TiO2 and Nb 107 Figure 4.2: Hawker diagrams part2: SiO2 vs. Rb and Ga 109 Figure 4.3: Hawker diagrams part1: Rb vs. Na2O+K2O and Nd vs. Nb 113 Figure 4.3: Hawker diagrams part2: Y vs. Nb and Y/Nb vs. Ce/Yb 115
Figure 4.4: Whole rock (<60% SiO2) N-MORB normalised LREES part1 117
Figure 4.4: Whole rock (<60% SiO2) N-MORB normalised HREES part2 118
Figure 4.5: Whole rock (>60% SiO2) N-MORB normalised LREE part1 122
Figure 4.5: Whole rock (>60% SiO2) N-MORB normalised LREE part2 123 Figure 4.6: Age vs. calculated ɛNd (T) for all whole rock isotope analyses 128 Figure 4.7: Nd-Sr isotopic separation of enriched/contaminated granitoids 130 Figure 4.8: Mg#/Fe# isotopic separation of enriched/contaminated granitoids 133 Figure 4.9: A-type granite classification (Whalen et al., 1987) of AAPG and POPG suites 144
xi Figure 4.10: A-type granite classification (Frost et al., 2001) of AAPG and POPG suites 146 Figure 4.11: Tectonic discrimination (Pearce et al., 1984a) of AAPG and POPG suites 147 Figure 4.12: A-type granite classification (Whalen et al., 1987) of IA+Syn and NHSG suites 149 Figure 4.13: A-type granite classification (Frost et al., 2001) of IA+Syn and NHSG suites 151 Figure 4.14: Tectonic discrimination (Pearce et al., 1984a) of IA+Syn and POPG suites 153 Figure 4.15: Western Shield and Nabitah Suture mafic classification 155 Figure 4.16: A geochemical summary map of all granitic suites 161 Figure 4.17: A geochemical classification for A-type mantle source 165 Figure 4.18: Evolution of the ANS and Australian A-type data using the mantle source classification scheme 166
Chapter 5 167 Figure 5.1: Zircon Age vs. Hf geochemistry for 18 granitic suites 172 Figure 5.2: Zircon Na vs. K geochemistry for 18 granitic suites 173 Figure 5.3: Zircon Na+K vs. LREE geochemistry for 18 granitic suites 176 Figure 5.4: Zircon Nb vs. U geochemistry for 18 granitic suites 177 Figure 5.5: Zircon Nb vs. Zr geochemistry for 18 granitic suites 184 Figure 5.6: Zircon REE geochemistry normalised to primitive mantle 185
Chapter 6 195 Figure 6.1: Geological age scatter produced by 3 zircon morphologies part 1 197 Figure 6.1: Geological age scatter produced by 3 zircon morphologies part 2 198 Figure 6.1: Geological age scatter produced by 3 zircon morphologies part 3 199 Figure 6.2: Examples of non-Gaussian probability distributions part1 201 Figure 6.2: Weighted average plots highlighting large MSWD values part2 202 Figure 6.3: Discrete age groups using Isoplot Software (Ludwig, 2000) part1 205 Figure 6.3: Discrete age groups using Isoplot Software (Ludwig, 2000) part2 206 Figure 6.4: 3 Discrete age groups using weighted average method part1 208 Figure 6.4: 3 Discrete age groups using weighted average method part2 209
xii Figure 6.5: Weighted average ages in sequential experimental time 211 Figure 6.6: Age vs. concordance and various isotope parameters part1 212 Figure 6.6: Age vs. concordance and various isotope parameters part2 213
Chapter 7 216 Figure 7.1: A geochemical summary map of all granitic suites 218 Figure 7.2: Petrogenetic model of the Asir-Tathlith microplates 227 Figure 7.3: Petrogenetic model of the Midyan-Hijaz microplates 232 Figure 7.4: Petrogenetic model of the Hijaz-Afif microplates 240
Chapter 8 241 Figure 8.1: A summary of the U-Pb concordia for all 452 zircons analysed 241 Figure 8.2: A summary probability diagram for all 452 zircons analysed 242 Figure 8.3: Arabian Shield U-Pb geochronology summary map 244 Figure 8.4: Hijaz-Asir microplate tectonic cartoon (part1) 245 Figure 8.4: Hijaz-Asir microplate tectonic cartoon (part2) 246 Figure 8.4: Hijaz-Asir microplate tectonic cartoon (part3) 247 Figure 8.4: Hijaz-Asir microplate tectonic cartoon (part4) 248 Figure 8.4: Hijaz-Asir microplate tectonic cartoon (part5) ` 249 Figure 8.5: Midyan-Hijaz microplate tectonic cartoon (part1) 252 Figure 8.5: Midyan-Hijaz microplate tectonic cartoon (part2) 253 Figure 8.5: Midyan-Hijaz microplate tectonic cartoon (part3) 254 Figure 8.5: Midyan-Hijaz microplate tectonic cartoon (part4) 255 Figure 8.5: Midyan-Hijaz microplate tectonic cartoon (part5) 256 Figure 8.6: Hijaz-Afif microplate tectonic cartoon (part1) 261 Figure 8.6: Hijaz-Afif microplate tectonic cartoon (part2) 262 Figure 8.6: Hijaz-Afif microplate tectonic cartoon (part3) 263 Figure 8.6: Hijaz-Afif microplate tectonic cartoon (part4) 264 Figure 8.7: Calculated ɛHf vs. U-Pb age (all Shield suites) 272 Figure 8.8: Calculated ɛHf vs. U-Pb age: IA and Syn suites part1 274 Figure 8.8: Calculated ɛHf vs. U-Pb age: PO and A suites part2 275
Appendix 1 303 Figure A1.1: Midyan terrane plutonic classification 307
xiii Figure A1.2: Al Bad Granite Super Suite field and petrographic photography 308 Figure A1.3: Jar-Salajah Complex and Subh Suite field and petrographic photography 315 Figure A1.4: Admar Suite and Mardabah Complex field and petrographic photography 318 Figure A1.5: Rithmah Complex field and petrographic photography and Hijaz terrane plutonic classification 320 Figure A1.6: Idah Suite field and petrographic photography and Ha’il terrane plutonic classification 324 Figure A1.7: Najirah Granite field and petrographic photography 329 Figure A1.8: Ad Dawadimi terrane plutonic classification 331 Figure A1.9: Ar Ruwaydah and Al Khushaymiyah Suites field and petrographic photography 333 Figure A1.10: Tathlith terrane plutonic classification 336 Figure A1.11: Al Hafoor Suite field and petrographic photography 337 Figure A1.12: Afif terrane plutonic classification 341 Figure A1.13: Haml Suite field and petrographic photography 342 Figure A1.14: Ibn Hashbal and Al Hawiyah Suites field and petrographic photography 350 Figure A1.15: Wadbah Suite field and petrographic photography and Asir terrane plutonic classification 352
Appendix 3 396 Figure A3.1: Makkah Suite zircon catholuminescence images 398 Figure A3.2: Shufayyah Complex zircon catholuminescence images 400 Figure A3.3: Jar-Salajah Complex zircon catholuminescence images 401 Figure A3.4: Subh Suite zircon catholuminescence images 402 Figure A3.5: Kawr Suite (sample kw42) zircon catholuminescence images 404 Figure A3.6: Al Hafoor Suite zircon catholuminescence images 405 Figure A3.7: Najirah Granite zircon catholuminescence images 406 Figure A3.8: Wadbah Suite zircon catholuminescence images 407 Figure A3.9: Ibn Hashbal Suite zircon catholuminescence images 408 Figure A3.10: Ar Ruwaydah Suite zircon catholuminescence images 409 Figure A3.11: Haml Suite zircon catholuminescence images 410
xiv Figure A3.12: Kawr Suite (sample kw51p) zircon catholuminescence images 411 Figure A3.13: Idah Suite zircon catholuminescence images 412 Figure A3.14: Al Khushaymiyah Suite zircon catholuminescence images 413 Figure A3.15: Malik Granite zircon catholuminescence images 415 Figure A3.16: Admar Suite zircon catholuminescence images 416 Figure A3.17: Al Bad Granite Super Suite zircon catholuminescence images 417 Figure A3.18: Al Hawiyah Suite zircon catholuminescence images 418 Figure A3.19: Mardabah Complex zircon catholuminescence images 419
List of Tables
Chapter 2 15 Table 2.1: Mineralogy and petrographic classification summary part1 38 Table 2.1: Mineralogy and petrographic classification summary part2 39
Chapter 3 40 Table 3.1: U-Pb geochronology summary from 19 Arabian suites part1 86 Table 3.1: U-Pb geochronology summary from 19 Arabian suites part2 87
Table 3.2: Hf isotope summary conducted on 19 dated Arabian suites part1 95 Table 3.2: Hf isotope summary conducted on 19 dated Arabian suites part2 96
Chapter 4 97 Table 4.1: Whole rock Sm, Nd and Sr isotopic summary for 20 Arabian suites and associated volcanics/mafic units 142
Table 4.2:Whole rock major element geochemistry summary and associated petrogenetic /tectonic classifications for all 20 Arabian suites 157 Table 4.3: Whole rock trace element geochemistry summary for all 20 Arabian suites 158
Chapter 5 167 Table 5.1:Zircon REE summary from 19 dated Arabian suites part1 193 Table 5.1: Zircon REE summary from 19 dated Arabian suites part2 194
xv Chapter 1: General Introduction.
1.1 Granite Overview.
Granites are the most abundant rocks in the earth’s upper continental crust, comprising a total volume of at least 3.49*109 km3, a mass of 1022 kg and a crustal composition of ~86 % by volume (Bonin, 2007). These contain a simple genetic mineralogy consisting of mainly quartz, feldspars, micas and amphiboles that encompass formation in a diverse range of tectonic environments including; convergent plate margins, orogenic fold belts, oceanic spreading centres and within plate pull apart basins (Bowden et al., 1984; Brown et al., 1984; Bonin, 1990). According to White (1979) and Clarke (1992), granites can be subdivided into 3 distinct groups: metaluminous I-types (ascent driven fractional crystallisation of contaminated mafic melts); peraluminous S-types (melting of continental crust); and peralkaline A-types (fractionation driven mantle affinity). This oversimplified subdivision conceals a number of petrogenetic processes that represent windows into the earth’s lithosphere.
1.2 Development of the A-type Classification.
The term A-type granite was first introduced by Loiselle and Wones (1979) for distinct granitoids low in CaO and Al2O, but high in total alkalis (K2O-Na2O), FeO/FeO+MgO and REE (Zr, Nb, Ta in particular). It was proposed that these were anorogenic (hence ‘A’-type) derivatives of alkali basalt fractionation with minimal crustal interaction. This classification was enhanced further by the introduction of new incompatible element parameters by Collins et al. (1982), Pearce et al. (1984a), Whalen et al. (1987) and Eby (1992). The ever increasing incorporation of more diverse granite types from Africa, Asia, Australia, North America and South America placed great strain on this terminology until the term ‘ferroan’ was introduced by Frost et al. (2001). Controversially, it was outlined by both Frost et al. (2001) and Bonin (2007) the term A-type granite was used too indiscriminately and should become obsolete. Frost and Frost (2011) suggested the term ‘ferroan granite’ should prevail to cover the diverse compositional and tectonic environments observed in generating these granites.
1 1.3 A-type Characteristics and Global Occurrences.
A-type granites are typically found at the termination of continental orogenic cycles and represent anorogenic rift magmatism derived from enriched mantle sources. The combination of lithospheric mantle and overlying crust generates A-type diversity characterised by: sub-trans/hypersolvous, rapakivi, porphyritic and granophyric textures; Na rich amphibole/pyroxene mineral assemblages; high alkali and low CaO contents (SiO2=70%, Na2O+K2O=7-11%, CaO<1.8%); high FeO ratios (0.8-0.9); high F (up to 5.4%); high Zr, Nb and Ta, low Sc, Cr, Co, Ni, Ba, Sr and Eu; and relatively low initial 87Sr/86Sr ratios of 0.703-0.712 suggestive of limited to moderate crust and mantle interaction (Eby, 1990).
Some A-type suites are of economic interest, possessing enrichment in Sn-W- Mo-Au-Ag-Nb-Ta REE and Y, U, Th and Zr. Significant world-class deposits include; the Carajas metallogenic province, Brazil (Dall’Agnol et al., 2005), Suzhou province China (Charnoy and Raimbault, 1994), Olympic Dam province, South Australia (Johnson and McCulloch, 1995) and Ha’il terrane, Saudi Arabia (Drysdall et al., 1984; Kuster, 2009). Associated with A-type granites, economic mineralising fluids are evidenced by fluorite and topaz precipitation controlled by brittle fracture zones in the upper crust (Agar, 1992), but whether they are magmatic or remobilised from country rocks remains unclear.
Brown et al. (1984) relate the geochemical characteristics of A-type granites to accreting island arc, continental arc and back arc environments. Consequently, these are found preserved in a wide variety of geological contexts including: continental cratons and shields (e.g. Archaean Yilgarn Craton, Australia, Superior Providence, Canada, and Arabian-Nubian Shield, Saudi Arabia); newly consolidated fold belts (e.g. Himalayas, India-Tibet and Taupo Volcanic Zone, New Zealand); ocean floors; and even other terrestrial planets (Moon) and asteroids (Bonin, 2007). This diversity is not seen in any other granitic group. Eby (1990) provides an excellent summary of the characteristics of A-type granites and their global occurrences.
2 1.4 Anorogenic Timing and Tectonic Significance.
The subduction-controlled convergence and collision between buoyant lithospheric fragments (e.g. Himalayas and Arabian-Nubian Shield) produce major orogenic episodes resulting in the juxtaposition of young and old core continental lithosphere (Stein and Goldstein, 1996). The appearance of anorogenic magmatism shortly after is not entirely disconnected with lithospheric orogenesis. According to Whalen et al. (1987), anorogenic granitoid emplacement is temporally related to collisional events with magmatic occurrences recorded immediately and up to ~50Ma after accretionary cycles. This suggests that a transitional stage between magmatic events must occur. Bonin (1990) discusses this using the Adrar des Iforas Orogenic Belt (Mali) as an example, but this could potentially apply to any of the A-type suites found in the Pan-African, North American, South American and Australian regions.
Accretionary cycles are summarised by Bonin (1990) as 3 magmatic stages that begin with subduction related melt zones producing low-K, calc-alkaline magmas and last up to 100Myrs e.g. Andes and Sierras (Bonin, 1990). This may be followed by a stage of continental collision (~30-50Myr duration) creating large volume, medium- high-K, calc-alkaline magmas, regional uplift and finally lithospheric denudation. Denudation may begin ~50Myrs after subduction ceases, last up to ~50-70Myrs afterwards and produce low Ca, iron rich, alkaline A-type formations that result from enriched asthenosphere upwelling beneath the over thrust plate.
This magmatic transition described by Bonin (1990) appears to have a sharp ‘window’ from subduction related calc-alkaline granites to post-orogenic alkaline suites. According to Barker (2010), some cases suggest the transition takes place in less than 10Myrs, resulting in synchronous emission of calc-alkaline and alkaline products. In any event, this scenario emphasises some fundamental questions involving the generation of A-type magmas in convergent and within plate settings, which are discussed further in Chapter 1.5.
It becomes apparent from the previous work outlined above that anorogenic magmatism symbolises the termination of orogenesis and provides the minimum accretionary age between continental fragments. This can help constrain the break up and assembly of supercontinents such as Rodinia and Gondwana (Chapter 1.6).
3 1.5 Petrogenetic Models for Generating Anorogenic Magmatism.
Despite the many petrogenetic unknowns of anorogenic suites, it is agreed (Frost and Frost 2011) that they are characterised by regions of uplift and crustal extension. Great controversy surrounds the mechanisms that induce extension and provision of lithospheric heat (Bonin, 2007), but the generation of this magmatism is convincingly argued to be non-crustal in origin, fractionated from variably contaminated mantle-like basalts and occurs in both rift zones and stable continental blocks (Pearce et al., 1984a). Partial melting of anorogenic sources requires heat supply and, whatever the origin, results in associated thermal erosion and/or mechanical delamination of lithospheric roots (Black and Liegeois, 1993).
Amongst prior explanations for the tectonic setting and alkaline affinities of A- type granites was the derivation from a residual crustal source left behind from a previous partial melting event (White, 1979). However, geochemical and isotopic developments in A-type classification have tended to implicate an enriched mantle source. To account for these geochemical and within plate parameters, Stein and Goldstein (1996) and Stein and Hofmann (1992) examined the Icelandic and Arabian Shield A-type suites and suggested a rising plume derived from the enriched lower mantle. The plume contributes to upper crustal extension and provides the heat to partially melt the lower crust and mix the two sources. It is notable that these plumes both follow lithospheric collision and occur in subduction as well as within-plate settings, an interesting, but coincident relationship that suggests induced asthenospheric plume upwelling may be created by either slab tear off or delamination.
According to Kay and Kay (1993), Schott and Schmeling (1998), Elkins-Tanton (2005) and Avigad and Gvirtzman (2009) slab tear seems unlikely to account for repeated cycles of accretion or long lived anorogenic magmatism. It is suggested that within plate A-type magmatism is generated by lithospheric root removal caused by denudation (lower crustal eclogite metamorphism) and accounts for subsequent extension pursuant to orogenesis. This mechanism is used to explain the Scandinavian rapakivi granites (Ramo and Haapala, 1995), Proterozoic North American suites (Anderson and Bender, 1989), Australian Lachlan Fold Belt and Delamerian suites (King et al., 1997; Turner et al., 1992; Foden et al., 2002) and Egyptian/Israeli Pan
4 African granitoids (Jarrar et al., 2008; Be’eri-Shlevin et al., 2009a; Be’eri-Shlevin et al., 2009b; Be’eri-Shlevin et al., 2009c; Be’eri- However, slab tear is still a favoured tectonic model for Mt Etna (Gvirtman and Nur, 1999) and sections of the Arabian- Nubian Shield (Flowerdew et al., 2013). Magmatic longevity could also be accounted for by the establishment of a lower crustal MASH (melting, assimilation, storage and homogenisation) zone in subducting environments (Smithies et al., 2011), but seems unlikely to account for within plate magmatism.
1.6 The East African Orogen and its Relation to the Arabian-Nubian Shield.
The Arabian-Nubian Shield (Figure 1.1) is characterised by juvenile Neoproterozoic island arc and continental accreted microplates that form a significant part of the thermo-tectonic-episode (Kennedy, 1964) known as the Pan-African orogenic event. Initially defined to differentiate Africa into late Precambrian cratons separated by mobile belts, the Pan-African terminology has been revised by Kroner (1985) and more recently by Veevers (2007) and Fritz et al. (2013) to incorporate the complex orogenic cycle from ~950-450Ma observed in many parts of what is now called Gondwana.
Veevers (2007) summarise Gondwana as a series of cratons (West African, Amazonia, Congo, Indian, and East Antarctica-Australia) that initially assembled by ~650-500Ma forming the Pan-Gondwana supercraton. Mesoproterozoic Rodinian dismemberment (Hoffmann, 1999) initiated Mozambique Ocean closure (Stern, 1994) stitching east and west Gondwana (Collins and Pisaversky, 2005; Cawood, 2005) forming what is currently referred to as the East African Orogen (Stern et al., 2006).
Focusing on the Arabian-Nubian Shield, Black et al. (1994) suggest a two stage orogeny commencing with a strong-collisional event following the west-dipping subduction east of the Air Region ~750-660Ma. This high pressure thrusting event produced orogenic calc-alkaline magmatism that was followed by development of north-south mega shear zones and ~650-580Ma calc-alkalic magmatism associated with an east dipping subduction zone west of the Air Region.
5 Figure 1.1: A regional map of the Middle East and Africa highlighting in yellow the Arabian- Nubian Shield (Shield boundary obtained from Johnson et al., 2011). This Shield forms a series of Proterozoic (2500- 542Ma) accreted terranes, which are interrupted by mobile orogenic belts and pull apart basins. The orogenic cycles associated with the Arabian-Nubian Shield emplace it firmly within the formation of Gondwana (~650- 500Ma). The Red Sea separates the two halves of the Shield, which rifted apart in the Tertiary (Vail, 1985).
6 Partial melting in response to post-tectonic delamination of the continental lithosphere produced many of the A-type suites in the Pan-African following supercontinental assembly (Goodge and Vervoort, 2006). This series of events produced the Arabian-Nubian Shield, which is arguably the largest piece of juvenile Neoproterozoic crust on earth (Patchett and Chase, 2002).
The Arabian-Nubian Shield preserves a tract of the Pan-African supercontinental accretionary cycle as a series of microplate collisions and magmatic events. Stoeser and Camp (1985) in conjunction with Veevers (2007) and Fritz et al. (2013) recognised 5 main phases of evolution in the Arabian-Nubian Shield:(1) rifting of the African craton (~1200-950Ma);(2) ensimatic island-arc development (~950-715Ma);(3) formation of the Arabian-Nubian neocraton by microplate accretion and continental collision (~715- 640Ma);(4) collision-related intracratonic magmatism and tectonism (~640-550Ma); and (5) epicontinental subsidence (<550Ma).
This Precambrian evolution produced Neoproterozoic orogenic belts (~870- 550Ma) consisting of a series of metasedimentary, metavolcanic, calc-alkaline and alkaline suites that form the basement crustal rocks. These range from ~4.5-45km thick in both northern Egypt and central Saudi Arabia respectively (Abdel-Rahman and Martin, 1990). These are unconformably overlain by Phanerozoic shallow marine sediments, which were deposited until the Tertiary uplift associated with the opening of the Red Sea (Vail, 1985).
1.7. Arabian Shield Geological Overview.
The Arabian Shield, arguably the most geologically complicated and interesting of the two Shields, can be subdivided into eight discrete terranes separated by five ophiolite-bearing suture zones. Camp (1984) provides excellent summary figures for the accreted terranes and related sutures, which also correlate with the Nubian side of the Shield in Africa. In general terms, the Shield structure consists of two parts: the western side comprising the Midyan, Hijaz, Jiddah and Asir island arc plates; and the eastern side composed of the Tathlith, Ha’il, Afif, Ad Dawadimi, and Ar Ryan plates which are of continental affinity (see Figures 1.2-1.5). This subdivision is also reflected
7 in the geochronological age (Stoeser and Frost, 2006), which appears to show a general younging trend towards the eastern side.
More recent tectonic evolution studies by Johnson et al. (2011) and Flowerdew et al. (2013) suggest the Arabian Shield is a protracted recorded of amalgamated juvenile tectonostratigrahphic terranes, composed of volcanosedimentary and plutonic assemblages (~850-620Ma) and are deformed by at least four periods of arc collision and suturing. These terranes are intruded by petrographically and geochemically diverse granitoids that are overlain by post-amalgamation basins and in turn, affected by multiple exhumation and erosion events.
Separating the two halves of the Shield is the geological ‘spine’ known as the Nabitah Orogenic Belt. This significant geographical feature is a ~100-200km wide currently mountainous zone that is thought to represent the late Neoproterozoic collision between western island arc and eastern continental plates (Stoeser and Camp, 1985; Stoeser and Frost, 2006). Recent geochronology and geochemical studies conducted by Flowerdew et al. (2013) confirms the Nabitah belt separates juvenile Neoproterozoic intra-oceanic arc terranes and proposes that plutons confined to its southern end form as a consequence of subduction slab roll back. The N-S trending Nabitah Orogenic Belt, together with smaller ophiolitic sutures, amalgamates adjacent terranes and is undoubtedly the site of a significant part in the magmatic history of the Shield, which is discussed shortly.
The late Proterozoic magmatic history of the Shield can be divided into four main phases defined and described in detail by Bentor (1985). These will be discussed in the following paragraphs. The earliest events include the emplacement of thick island arc bimodal volcanic sequences from ~950-715Ma that are confined to the western side of the Shield, particularly in the Midyan, Hijaz and Asir terranes (Figure 1.2). Microplate accretion and suture formation from ~715-640Ma resulted from the closure of these oceanic basins, leaving behind ophiolitic evidence of their existence.
Collision occurred along what is now called the Yanbu and B’ir Umq Sutures in the west (island Arc plates) and the Nabitah and Halaban Sutures in the east (continental plates). This stage was magmaticly the most productive resulting in extensive north- south trending granitoids in the eastern side of the Shield (Figure 1.3). As suggested
8 Figure 1.2: A geological map of the Arabian Shield modified from Johnson (2006), highlighting the Cryogenian age intrusive rocks scattered throughout the Shield. These intrusives are not involved in terrane accretion, but form the bimodal island arc rocks associated with oceanic basins formed in the Rodinian break-up stage (1250-715Ma). Note the high concentration of island arc rocks located in the western part of the Shield, in particular, the Asir terrane. The dashed suture represents the future Jiddah terrane boundary running through Makkah. It should also be noted that the Red Sea coast line is not presented here, but rather the Arabian Shield outline with major cities highlighted in bold. by Johnson et al. (2011), Nabitah collision was not synchronous, but started in the north between Midyan-Hijaz-Afif at ~680Ma while still experiencing subduction in the southern Shield between the Asir-Tathlith-Afif plates. Geochronological evidence
9 presented by Johnson (2006) and Johnson et al. (2011) suggest further collision along the Nabitah Orogenic Belt converted the once subducting orogenic belt into a strike slip style system. It is speculated all terranes were sutured by ~640Ma.
Figure 1.3: A geological map of the Arabian Shield modified from Johnson (2006), highlighting the Cryogenian-Ediacaran age intrusive rocks scattered throughout the Shield. These intrusives are directly involved in terrane accretion associated with ocean closure and suture formation, but also include some post-suturing A-type plutons. This is considered to be subduction style magmatism resulting from the collision of the western and eastern terrane plates. Note the high concentration of plutons located in the eastern part of the Shield. This stage also saw the formation of the Nabitah Orogenic Belt running down the spine of the Arabian Shield. It should also be noted that the Red Sea coast line is not presented here, but rather the Arabian Shield outline with major cities highlighted in bold.
10 Post-orogenic magmatism at <640Ma highlights the cessation of the microplate accretion (Figure 1.4). According to Johnson (2006) this post-collisional magmatism continued for ~80Ma and marks a significant switch from calc-alkaline to alkaline dominated granites (Black and Liegeois, 1993). The formation of the SE-NW striking Najd fault-system, primarily located in the Afif terrane, is speculated by Johnson et al. (2011) to be the last tectonic event caused by the final assembly of the Ar Ryan continental plate. It is thought that the Ar Ryan plate forms part of a bigger continent that extends under the eastern Phanerozoic cover and is exposed in Oman. This final collision caused lateral displacement the Nabitah Orogenic Belt.
The current regional unconformity at 542Ma marks lithospheric stabilisation and peneplain formation in the Shield. These Cambrian-Ordovician sediments described by Johnson (2006) covered vast areas of the Shield concealing the granitic basement underneath. Permian cover defines the ‘empty quarters’ in the eastern side of Saudi Arabia associated with petroleum deposits. Tertiary rifting associated with the opening of the Red Sea (Vail, 1985) has produced the only magmatic activity recorded thus far in the Shield since magmatic cessation at 542Ma.
The interpretation of the geological reconstruction of the Arabian Shield had significant contributions in the 1980’s and early 1990’s, particularly by Camp (1984), Bentor (1985), Stoeser and Camp (1985), Abdel-Rahman and Martin (1990), Stein and Hofmann (1992), Black and Liegeois (1993), Black et al. (1994), Johnson and Stewart (1995) and Stein and Goldstein (1996). More recent studies by Johnson (2003), Johnson et al. (2003), Johnson (2006), Stoeser and Frost (2006) and Johnson et al. (2011) summarise the data gathered in the Arabian Shield thus far. Extensive and high quality geochronology data sets are presented in Kennedy et al. (2004), Kennedy et al. (2005), Kennedy et al. (2010a), Kennedy et al. (2010b), Kennedy et al. (2011), Johnson and Kattan (2007) and summarised in Johnson et al. (2011). However, many of the geological suites remain unassigned (Figure 1.5) and are currently under investigated.
Some understanding of the geological reconstruction has been extrapolated through recent studies conducted in Egypt and Israel around the Sinai Peninsular and Sudan, Africa (Avigad and Gvirtzman, 2009; Be’eri-shelvin et al., 2009a; Be’eri- Shlevin et al., 2009b; Be’eri-Shlevin et al., 2009c; Be’eri-Shlevin et al., 2010; Eyal et al., 2010; Goodenough et al., 2010; Stern and Johnson, 2010; Krienitz and Haase, 2011;
11 Figure 1.4: A geological map of the Arabian Shield modified from Johnson (2006), highlighting the Ediacaran age intrusive rocks scattered throughout the Shield. These post- tectonic intrusives are within plate and somewhat evenly distribution across the Shield. Note that these are the only post-tectonic suites with current published geochronological data. There are likely to be more, but these are currently classified as unassigned or poorly age constrained Cryogenian-Ediacaran intrusives. It should also be noted that the Red Sea coast line is not presented here, but rather the Arabian Shield outline with major cities highlighted in bold.
El-Baily and Hassen, 2012; Morag et al., 2012). This indirect approach awaits more detailed studies gathered within the Arabian Shield. This project has placed special
12 emphasis on Arabian Shield post-orogenic suites that are emplaced in two types of geological setting: 1) convergent suture zones (Figure 1.3); and 2) within plate or ‘back arc’ settings (Figure 1.4).
Figure 1.5: A geological map of the Arabian Shield modified from Johnson (2006), highlighting the unassigned Neoproterozoic intrusive rocks scattered throughout the Shield. These intrusives currently contain no geochronological data or they are poorly constrained. Geographical location of these suites, in particular the Nabitah Orogenic Belt, suggests that they are associated with suture formation or within-plate magmatism. It should also be noted that the Red Sea coast line is not presented here, but rather the Arabian Shield outline with major cities highlighted in bold.
13 1.8 Aims.
The primary objective of this research project is to establish an extensive geochronological and geochemical Arabian Shield pluton database with particular emphasis on post-orogenic magmatism and describe its petrogenetic and tectonic implications in relation to continental accretion. A comprehensive summary of previous work has been provided, highlighting important and extensive data sets that construct the current geology and geodynamic models of the Arabian Shield. However, many drawn conclusions are still extrapolated from neighbouring Middle Eastern and African countries and selected intrusives are geochronologically and geochemically under investigated.
Post-orogenic magmatism is a well established and important cycle in continental assembly. Given granitic diversity immediately following and pursuant to collisional episodes, it is worthwhile exploring further the mantle geochemistry in which they are derived. Particular attention will be paid to geochronological evolution (U-Pb) and mantle source behaviour (whole rock geochemistry and zircon Hf isotopes) providing new insights into their petrogenesis and relationship with Gondwanian supercontinental assembly. It is then envisaged that this classification can be applied to similar regional Arabian-Nubian Shield post-tectonic cycles.
14 Chapter 2: Petrographic Constraints on Sampled Arabian Shield Plutons; Subdivision of A-type Suites.
2.1 Introduction.
The late Neoproterozoic-Cambrian tectonic events that formed the Arabian Shield (Chapter 1.7) resulted in a wide range of granite types including; metaluminous I-types, peraluminous S-types and peralkaline A-types (Chapter 1.1). According to existing maps and data from Johnson (2006) and Johnson et al. (2011) respectively, many post-orogenic plutons directly intrude major suture zones such as the Nabitah Orogenic Belt, but also are spatially within plate suites isolated from suture zones (Figures 1.3 and 1.4). The existing petrographic and geochronological information on many of these post-orogenic plutons describes these as A-type suites. However, the grouping of all endmembers into one A-type category fails to recognise the potential petrogenetic diversity as indicated by their spatial relationship in the Arabian Shield. The range in tectonic environments possessed by the Arabian Shield provides a convenient basis to discriminate the classic A-type, strictly rift-related, basaltic fractionation category as first described in the early years of classification (Loiselle and Wones, 1979).
The aim of this section is to identify mineralogical discriminators that clearly separate the sampled granitoids into I-S and A-type categories. Furthermore, highlight the misplaced reliance on mineralogical and textural (perthitic texture, decompression settings) characteristics alone to categorise A-type granites, hence their petrogenesis and reinforce the need for further geochronological (Chapter 3) and geochemical (Chapter 4) data to discriminate them.
15 2.2 Sample Selection.
As outlined in Chapter 1.7, the Arabian Shield consists of accreted Neoproterozoic oceanic and continental arc fragments adjoined by the Nabitah Orogenic Belt. The record of accretion is preserved as a series of pre-, syn- and post- collisional geological units. This work focuses on the undeformed post-tectonic series that appear to record a change in mantle chemistry based on results in this study. The majority of these intrusive suites cross-cut terrane boundaries and are Cryogenian- Ediacaran (650-542Ma) in age and are thought to represent post-tectonic activity associated with the Shield (Figures 1.3 and 1.4).
Plutonic suites were selected using 1: 100, 000 geological maps and technical reports (SGS-TR-2006-4) complied by Johnson (2006) and availability/ease of access of exposed outcrop from Google Earth. Emphasis was placed on the structural relationships of granitoids that cross-cut older geological units and contained little if any geochronological or geochemical data.
Fieldwork commenced on January 12th 2011 and concluded on February 16th of the same year. This consisted of transects across each of the 8 terranes with opportunistic sampling of the desired plutons (Figure 2.1). Exposed outcrop was limited, but sampling at least 50m apart within a suite was desirable. This reduced the local bias of geochronological and geochemical results by ensuring homogeneity and robustness across the suite. Some suites exhibited internal magmatic mixing phenomena alongside unconformable older basement interaction that was also sampled whenever possible.
The collection consisted of 216 samples including; mafic volcanics and plutonic units, metamorphosed sediments, felsic volcanics and undeformed alkali-granites. 137 of these were selected, cleaned and shipped to the University of Adelaide, Australia to represent the 26 different geological units sampled from 8 Shield terranes (Figure 2.1). All samples were cleaned, sawn and crushed in preparation for petrographical (Chapter 2.3), geochronological (Chapter 3) and geochemical (Chapter 4) analysis. A detailed catalogue of all samples collected can be viewed in Appendix 1.
16 Figure 2.1: A geological map of the Arabian Shield modified from Johnson (2006) highlighting the sampled units spread across the 8 different terranes. Red units are thought to represent post- tectonic granitoids, blue units are amalgamation basins and green units are mafic intrusives. The dark blue boundaries are accretionary suture zones associated with the closure of two microplates. A detailed catalogue of the units sampled can be viewed in Appendix 1.
17 2.2.1 Adopted Classification Nomenclature.
This section has adopted the nomenclature scheme developed by De la Roche et al. (1980). This is a major element geochemically based scheme and is simply adopted as a means of classifying and subdividing the Arabian Shield suites without prior petrographic assumptions.
Classical discrimination diagrams such as the quartz, orthoclase, albite, anorthite
(QAPF) and SiO2 vs. Na2+K2O (TAS) systems (Steckeisen, 1976; Le Bas et al. 1986) are commonly used, but involve assumptions with normative quartz-albite-anorthite that are calculated before applying a mineralogical classification. These models recalculate major element data into respective leucocratic mineral components, but discard mafic components, which are commonly seen in A-I type granites. Later work by Middlemost (1994) suggests that the QAPF is by itself unable to classify the rocks in the field surrounding the plagioclase endmember.
The decision to adopt the De la Roche et al. (1980) system over the more traditional QAPF and TAS models is based on petrological observations. In particular, the Mardabah Complex contains mafic olivine scattered amongst perthitic alkali- feldspar with <20% plagioclase, which would petrologically classify this suite as a syenite. This is clearly reflected in the De la Roche et al. (1980) model, but the normative QAPF Streckeisen system claims a monzonite with much more calculated plagioclase (>35%). A-type hypersolvous granites have modal alkali-feldspar whose composition falls towards the middle of the albite-orthoclase join (low pressure/H2O content) creating a significant difference between mode and normative fields. Consequently, the calculated CIPW normative values significantly underestimate the amount of alkali-feldspar and overestimate the amount of plagioclase.
TAS diagrams by Le Bas et al. (1986) and Middlemost (1994) are more reliable, but many of the granitic suites in this section contain intermediate-mafic units which are more reliably plotted on the De la Roche et al. (1980) diagram. In any case, the importance of accurately classifying granitic rocks becomes apparent when determining their petrogenetic and geotectonic relationships (Chapter 7).
18 2.3 Granitoid Petrography.
This section contains petrographic descriptions of intrusive suites representing classic I-S and A-type mineralogy found in the Arabian Shield. Although 20 intrusive suites are described, 5 are selected to represent various parts of the Shield: Jiddah terrane (Makkah Suite), Hijaz terrane (Shufayyah Complex - Yanbu-Suture), Asir terrane (Kawr Suite - Nabitah Suture), Ha’il terrane (Abanat Suite) and the Ad Dawadimi terrane (Malik Granite). The remaining 15 suites: Admar Suite, Al Bad Granite Super Suite, Al Hafoor Suite, Al Hawiyah Suite, Al Khushaymiyah Suite, Ar Ruwaydah Suite, Haml Suite, Ibn Hashbal Suite, Idah Suite, Jar-Salajah Complex, Mardabah Complex, Najirah Granite, Rithmah Complex, Subh Suite and Wadbah Suite are catalogued in Appendix 1.
The summary classification Figure 2.11 utilises published data from the Arabian-Nubian Shield to compare and contrast data obtained in this study. The published data are divided into 4 distinct MORB, I-type, fractionated A-type and within plate granitoid fields based on geochronological and geochemical constraints (predominantly tectonic classification, major and trace element and Nd-Sm isotope correlations) from existing papers. The references associated with these granitic fields are as follows: Mafic, I-type and Fractionated A-type Fields: Israel (Beyth et al., 1994), Egypt (El-Sayed et al., 2002), Oman (Gass et al., 1990), Sudan (Klemenic and Poole, 1988) and an extensive data base (~250 points) from Jordan (Jarrar et al., 2003; Jarrar et al., 2008). Within plate A-type Field: Israel (Mushkin et al., 2003), Sudan (Klemenic and Poole, 1988; Harris et al., 1983), Yemen (Cole et al., 1992; El- Gharbawy, 2011) and Egypt (Abdel-Rahman and Martin, 1990; El-Baily et al., 2009; El-Sayed et al., 2002; Katzir et al., 2007).
19 2.3.1 Makkah Suite (dm). A mineralogical summary of this suite is presented in Chapter 2.4.
The Makkah Suite forms a series of subangular plutons, locally known as the Milh and Sharqah Complexes (Johnson, 2006), spread across the northern part of the Asir terrane. This compositionally diverse series of rocks is exposed by a steep ascent to At Ta’if known as the Sarawat Mountains ~50km from Jeddah (Figure 2.2). This suite is poorly constrained at 817-687Ma, but has been classified as Tonian based on geochronological data from an identical suite in the neighbouring Nubian Shield (Johnson, 2006). However, new U-Pb data from Kenned et al. (2011) presents a crystallisation age of 859±1Ma.
Mafic gabbroic units often display sharp cross-cutting dyke contacts with more felsic tonalite rich patches and fresh road cuttings allowing ample sampling (Figure 2.2). A total of 3 samples were collected from the southern part of the Makkah Pluton (see Appendix 1.2). Medium-fine grained gabbroic autoliths mingled with coarse tonalite/granodiorite was also evident (Figure 2.2). Some mingling patches, up to several meters across, showed diffuse mineralogical boundaries with reduction of pyroxene assemblages towards the granodiorite unit. The mafic units are composed of plagioclase (~50%), clinopyroxene (~30%), orthopyroxene (~10%), hornblende (~5%) and olivine + magnetite (<5%) that define a gabbro-diorite (Figure 2.3), but are not petrographically described here. The mafic units appear to transform into biotite schists patches along localised fault boundaries. This slight deformation (possibly greenschist grade facies) is consistent with the syn-tectonic nature of the suite, but overall, this suite is considered undeformed.
A chlorite schist was also sampled (Appendix 1.2), but ~20km south of this location on the outskirts of At Ta’if. These greenschist facies rocks belong to the deformed At Ta’if Group and are thought to form part of an older (840-815Ma) frontal arc (Johnson, 2006). This outcrop showed thrusting to the west, which is consistent with westward migrating island arcs. However, for the purposes of this project, this suite will not be described in detail.
20 Figure 2.2: A) Well exposed mountain ranges composed of Makkah Suite intrusives near At Ta’if east of Jeddah. B) Dyke swarms ranging from gabbros to rhyolites are scattered throughout this suite. These are very sharp contacts with distinguishable relative ages. C) Magma- mingling between mafic and felsic endmembers. A total of 3 samples were collected here together with one micacous schist (At Ta’if Group). D) A representation of the medium/coarse-grained tonalites obtained from the Makkah Suite. E) A petrographic photograph taken in plane-polarised light of the same tonalite sample. Note the abundant hornblende and plagioclase with little alkali-feldspar present. The opaques seem to be confined to the hornblende crystals. F) The same petrographic photo taken in cross-polarised light. The location of all samples collected and a complementary catalogue of this suite is displayed in Figure 2.10 and Appendix 1.2 respectively.
21 The Makkah Suite has a predominately silica poor mineralogy with the felsic endmember composed primarily of plagioclase (~50%), hornblende (~20%), quartz (~20%), biotite (<5%) and alkali-feldspar (<5%) that define a tonalite (Figure 2.3). These are most likely fractionated from parent gabbros. Accessory phases include magnetite, zircon and titanite. Textures are homogeneously granular, but porphyritic sections containing coarse ~2-5mm plagioclase crystals are observed.
Figure 2.3:A Plutonic classification scheme modified from De la Roche et al. (1980) of Makkah Suite samples (red circles) from the Jiddah terrane. This diagram indicates that the mafic samples collected are classified as gabbro-diorites, whilst the more felsic endmember is a tonalite.
Adcumulate euhedral-subhedral plagioclase forms the interlocking network between the cumulate subhedral hornblende grains (Figure 2.2). Post cumulate interstitial anhedral quartz is confined to the plagioclase matrix. Magnetite appears in both early and late stages confined as hornblende inclusions and at junctions of interstitial quartz and feldspar respectively. Zircon appears as euhedral <0.2mm crystals in both hornblende and plagioclase. This suggests two stages of magnetite-zircon crystallisation. Interstitial titanate is rare and confined to the matrix forming overprints on plagioclase.
22 2.3.2 Shufayyah Complex (su). A mineralogical summary of this suite is presented in Chapter 2.4.
The Shufayyah Suite forms a series of irregular shaped plutons spread across the southern part of the Hijaz terrane. These discordant plutons lie ~150km south east of Yanbu al Bahr, mid way between the Yanbu and B’ir Umq Sutures. The Shufayyah suite is emplaced into the already folded rocks of the Birak (805Ma) and Al Ays Groups (745-700Ma) and has been dated at 715Ma (U-Pb in zircon), which according to Johnson (2006) is undocumented, but broadly coeval with the Salajah batholith to the north of Yanbu al Bahr.
The well exposed angular nature of the outcrops provided ideal sampling conditions. A total of 4 samples were collected here including one country volcanic (see Appendix 1.3). The granitic plutons exhibited obvious contact relationships between older Al Ays Group volcanics (Figure 2.4). No evidence of mingling or deformation was observed in the granitic plutons. However, some sections (<1m) exhibit a reduction in hydrous ferromagnesian mineral assemblages and are often associated with quartz and muscovite veining.
Shufayyah tonalites are primarily composed of plagioclase (~60-65%), quartz (~20%), hornblende (~10%) and biotite (~10%) that define a tonalite (Figure 2.4). Accessory phases include alkali-feldspar and magnetite/ilmenite. Textures are homogeneously porphyritic defined by ~5-10mm euhedral-subhedral plagioclase grains (Figure 2.4). These coarse grains are surrounded by finer (<2mm) subhedral-anhedral plagioclase, quartz and minor orthoclase. Hydrous subhedral hornblende exclusively hosts magnetite inclusions and together with coarse plagioclase, form the early phases of crystallisation. Anhedral quartz and biotite are the only interstitial phases observed and appear to form at plagioclase intersections.
23 Figure 2.4: A) Exposed rolling hills composed of the Shufayyah Complex marked by a contact with the Al Ays Group volcanics. A total of 3 samples were collected here. B) A representation of the coarse grained tonalites obtained at the contact. Note the abundance of amphiboles and large plagioclase crystals. C) A petrographic photograph taken in plane-polarised light of the same granite sample. Note the abundant hornblende hosting the majority of the opaques. D) The same petrographic photo taken in cross-polarised light. Plagioclase alteration is caused by weathering. E)A Plutonic classification scheme modified from De la Roche et al. (1980) of the Shufayyah Complex. These 3 samples are classified as tonalities and reflect typical ‘I-type’ intrusives that are associated with the Yanbu Suture. The location of all samples collected and a complementary catalogue of this suite is displayed in Figure 2.10 and Appendix 1.3 respectively.
24 2.3.3 Kawr Suite (kw). A mineralogical summary of this suite is presented in Chapter 2.4.
The Kawr Suite is a large body of relatively small discordant, subrounded to circular plutons spread over the southeastern Asir terrane. The emplacement of these undeformed mafic-felsic plutons are characterised by steep high relief mountains that intrude sections of the Nabitah Orogenic Belt. This suite has been directly dated (U-Pb in zircon) at 650-620Ma, but localised plutons have been documented at 605Ma (Johnson, 2006).
Fortunately, these granitic plutons are currently quarried for granite, thus providing ample opportunity to obtain fresh samples. A total of 34 samples were collected from across the various quarries visited (see Appendix 1.8). The Kawr Suite exhibits a range of subunits ranging from diabase/gabbro-dioirte-granite-alklai-feldspar granite, which frequently show mingling interactions (Figures 2.6 and 2.7). These spectacular mingling interactions were observed on the wall rocks and cut blocks inside the quarry. Reduction in grainsize and/or concentration of hydrous biotite is often marked by flow banding texture around pyroxene/olivine-bearing autoliths (Figure 2.6). This interaction predominantly occurred in the pink alkali-feldspar granites, but was also observed in the finer grained grey granites.
Some sections of the quarry displayed sharp compositional contacts from coarse pink alkali-feldspar granites to fine grey monzogranite (Figure 2.7). This relatively sharp change is thought to be an exposed magma chamber or sill like structure that defines a change in cooling rate. Some exposed sections also displayed a transition from autolthic gabbros incorporated in grey granites to pink alkali-feldspar mingling and finally to Na-rich amphibole/pyroxene granites. This is thought to resemble the progressive magmatic fractionation that occurred in the Kawr Suite.
Cumulate Gabbros: Sample kw19.
The majority of the mafic autoliths are dioritic in composition and predominantly composed of plagioclase and pyroxenes. However, some endmembers contain plagioclase (~45%), olivine (~35%) and clinopyroxene (<20%) that define a
25 gabbroic composition (Figure 2.5). Minor and accessory phases include orthopyroxene and magnetite. Textures are homogeneously equigranular defined by an interlocking network of cumulate plagioclase. Euhedral to subhedral coarse (~1-5mm) olivine with magnetite inclusions mark the first stage of crystallisation. These are randomly distributed and exhibit slight serpentinisation with occasional clinopyroxene rims (Figure 2.6). Euhedral cumulate plagioclase fills the voids between olivine crystals and appears to show orientation consistent with cumulate magmatic settling. Magnetite occurs as both plagioclase inclusions and at mineral junctions, indicating continuous magnetite crystallisation.
Figure 2.5:A Plutonic classification scheme modified from De la Roche et al. (1980) of the Kawr Suite in the Asir terrane. This suite is quite a diverse package of rocks that range from gabbros to tonalites and alkali-granites. The geochemical parameters that distinguish these intrusives from other Arabian Shield suites are discussed in Chapters 4.4.4 and 7.
26 Figure 2.6: A) Exposed quarried hills composed of the Kawr Suite granites near Bishah, just west of the Nabitah Orogenic Belt. A total of 34 samples were collected from the various quarries. B) Mafic mingling interaction with pink granites. Note the flow texture around pyroxene-bearing autoliths. C) Various styles of mafic mingling between different granitic units. D) A representation of the cumulate gabbros obtained at the quarries. E) A petrographic photograph of the same gabbro sample taken in plane-polarised light. Note the slight serpentinisation of olivine. F) The same petrographic photo taken in cross-polarised light. Note the abundant olivine, cumulate plagioclase and clinopyroxene rimming some olivine grains. G) A representation of the porphyritic granites obtained. Note mingling mafic and felsic patches. H) A petrographic photograph taken in plane-polarised light of the same granite sample. Note the intrusive nature of the mafic enclave into the porphyritic granite. I) The same petrographic photo taken in cross-polarised light. Note the distinction between plagioclase-clinopyroxene mafic enclaves compared to the finer quartz-alkali-feldspar assemblages in the surrounding granite. The location of all samples collected and a complementary catalogue of this suite is displayed in Figure 2.10 and Appendix 1.8 respectively.
27 Pink Granites: Sample kw35.
These samples have homogeneously porphyritic texture, but are often interrupted with mafic and felsic enclaves, thus causing a variation in mineral composition (Figure 2.6). Granite mineralogy is composed of quartz (~30-35%), alkali- feldspar (~30%), plagioclase (~25%) and biotite (<10%) that defines a monzogranite (Figure 2.5). The majority of coarse (~5-10mm) pink feldspar is slightly weathered alkali-feldspar and plagioclase that exhibits microperthitic texture. The void spaces between coarse grains are filled with finer (<2mm) interlocking quartz and alkali- feldspar. Later stage interstitial biotite and less common hastingsite appear at quartz- feldspar intersections. Hornblende is occasionally observed and contains magnetite inclusions
Some sections of this suite exhibit mafic enclaves (Figure 2.6). These mafic zones are composed of coarse (~1-5mm) clinopyroxene (~50%), some containing actinolite alteration, and finer (<2mm) subhedral-anhedral adcumulate plagioclase nestled between clinopyroxene spaces. Interstitial anhedral hornblende also appears here. The relatively poor crystal structures combined with little interaction with granitic minerals, suggests rapid infiltration and cooling/crystallisation. Felsic enclaves are also apparent in this sample (Figure 2.6). Apart from the reduction in grainsize, these are mineralogically identical to the host granite (quartz, alkali-feldspar-plagioclase- hornblende and interstitial biotite and hastingsite). Small patches of quartz-alkali- feldspar intergrowths mark the appearance of granophyric texture.
Green-Grey Alkali-feldspar Granites: Sample kw21.
These are texturally and mineralogically typical hypersolvous granites composed of quartz (~45%), microperthite (~40%), plagioclase (<10%), aegirine (<10%) and biotite (<5%) that define alkali-granite/syenogranite (Figure 2.5). Minor and accessory phases include biotite, arfvedsonite, titanite, magnetite and apatite. Textures are equigranular characterised by coarse (~5-10mm) perthitic feldspars and quartz (Figure 2.7). However, some sections are more porphyritic containing quartz- alkali-feldspar intergrowths sandwiched between larger perthitic grains (Figure 2.7).
28 Two phases of quartz crystallisation are apparent: initial coarse grains (~1-5mm) of subhedral quartz are followed by interstitial anhedral quartz rimming the intersections of larger perthitic grains. The Na-rich ferromagnesian minerals are predominantly aegirine, some showing 2 cleavages at 900. Biotite is exclusively an interstitial phase forming at the intersections of perthitic grains and occasionally containing small (<1mm) aegirine and apatite inclusions. Interstitial titanite is also observed at the junctions of coarse perthitic-quartz grains.
Grey Granite/Pink alkali-feldspar Granite: Sample kw52b/52p.
This sample exhibits the compositional contact from coarse pink to fine grey granite (Figure 2.7). Perthite (~70%), quartz (~20%), plagioclase (~5%) and biotite (~5%) are the main constituents of the coarse pink granite, whilst quartz (~30-35%), alkali-feldspar (~30%), plagioclase (~25%), biotite (<10%) and hornblende (<5%) are the components of the finer grey granite. These minerals define a monzogranitic and alkali-feldspar granitic composition respectively (Figure 2.5).
The pink granites are homogeneously equigranular defined by coarse (~1-5mm) subhedral quartz and perthitic feldspars (Figure 2.7). Microcline (containing microperthitic texture) is commonly seen and composes ~20-25% of the feldspars. Biotite and quartz appear to form in two stages of crystallisation. Large (~1-5mm) subhedral grains of biotite (including magnetite inclusions), quartz and alkali-feldspar mark the initial crystallisation phases. This is then followed by fine (<1mm) interstitial biotite and quartz, observed at the intersections of coarse perthitic grains.
Although mineralogically similar, the abrupt change in grainsize and texture marks the contact of the fine grained grey granite (Figure 2.7). The porphyritic nature of this granite is defined by coarse (~1-3mm) subhedral quartz and plagioclase grains surrounded by finer (<1mm) interlocking anhedral quartz and alkali-feldspar. Biotite is more abundant, but finer grained and still remains an interstitial phase forming anhedral grains at the junctions of quartz and feldspar. The introduction of early stage hornblende hosting magnetite inclusions is also apparent. Interstitial hastingsite is also observed scattered around the finer grain feldspar sections.
29 Figure 2.7: A) Exposed quarried hills composed of the Kawr Suite granites near Bishah, just west of the Nabitah Orogenic Belt. A total of 34 samples were collected from various quarries. B) Mafic mingling textures with alkali-granites. C) A clear distinction between granitic types thought to represent internal chamber processes. D) A representation of the sampled alkali-granites. Note the abundant pyroxenes. E) A petrographic photograph of the same granite sample taken in plane-polarised light. Note the microperthitic feldspars and presence of aegirine. F) The same petrographic photo taken in cross-polarised light. Note the patches of granophyric texture G) A representation of the sharp compositional boundary between the coarse pink alkali-feldspar and finer grey granites obtained at the quarry contact. H) A petrographic photograph taken in plane-polarised light of the same granite sample. Note the boundary between the coarse granite and finer porphyritic granite. I) The same petrographic photo taken in cross-polarised light. Note abundant exsolution textures in the coarse feldspar grains. The location of all samples collected and a complementary catalogue of this suite is displayed in Figure 2.10 and Appendix 1.8 respectively.
30 2.3.4 Abanat Suite (aa). A mineralogical summary of this suite is presented in Chapter 2.4.
The Abanat Suite is a highly evolved granitic unit forming extensive rounded and ring like plutons spread across the Afif, Ha’il and Ad Dawadimi terranes in the northeastern part of the Shield. These units are often expressed by impressive high relief mountains such as the Aja Mountains near Ha’il (Figure 2.8). These are undeformed and have been directly dated (U-Pb in zircon) at 585-570Ma and are associated with Sn-W/Nb-La REE mineral deposits (Johnson, 2006).
Plutons often displayed sharp cross-cutting rhyolitic dykes with fresh road cuttings allowing ample sampling. A total of 4 samples were collected including one rhyolite dyke (see Appendix 1.4). The rhyolite is predominantly composed of alkali- feldspar (~45%), quartz (45%) and minor plagioclase and biotite (<10%) phenocrysts. Unusual zones of grainsize reduction coinciding with increased biotite occurrences were also observed, predominantly confined to the edges of dykes (presumably hydrous fluids/wall rock interaction). The pink coarse grained alkali-granites show no evidence of deformation or magma-mingling. However, localised concentrations of green Na- amphiboles and pyroxenes were evident scattered around the exposed outcrops.
Abanat Suite units are homogeneous in both mineralogy and texture composed of perthite (~65-70%), quartz (~15%), aegirine (~10%) and plagioclase (~5%) that define alkali-granite (Figure 2.8). Accessory phases include arfvedsonite and magnetite. Textures are equigranular characterised by coarse (~5-10mm) perthitic feldspars and quartz (Figure 2.8). Subhedral-anhedral perthitic feldspars dominate, but there are a few multi-twinned plagioclase grains sandwiched between perthite. Anhedral quartz occurs in multiple phases: large (~1-5mm) grains coexisting with perthite and smaller (<1mm) interstitial grains at perthitic and amphibole junctions. Aegirine (~1-10mm) is the dominant Na-rich ferromagnesian mineral, but there are a few occurrences of arfvedsonite located in perthitic junctions hosting aegirine inclusions (Figure 2.8). Magnetite is rarely seen and is confined to aegirine crystals. Zircon is almost non-existent, but evidence of yellow radiometric halos in perthite and cracking in quartz is observed.
31 Figure 2.8: A) Jagged high topographic mountain ranges composed of the undeformed Abanat Suite. B) A representation of the alkali-granites collected from the Abanat Suite Note the large alkali-feldspar grains and blue-green amphiboles. C) A petrographic photograph of the same granite sample taken in plane- polarised light. Note the interaction of arfvedsonite hosting aegirine grains. D) The same petrographic photo taken in cross-polarised light. Note the abundant hypersolvous perthitic feldspar. E)A Plutonic classification scheme modified from De la Roche et al. (1980) of the Abanat Suite. This is typical Na-rich ferromagnesian-bearing hypersolvous A-type granite associated with economic REE deposits. The location of all samples collected and a complementary catalogue of this suite is displayed in Figure 2.10 and Appendix 1.4 respectively.
32 2.3.5 Malik Granite (kg). A mineralogical summary of this suite is presented in Chapter 2.4.
The Malik Granite is composed of two isolated elliptical shaped plutons confined to the northeastern margin in the Ad Dawadimi terrane. These undeformed leucocratic granites are not directly dated, but are classified as 620-15Ma based on conformable relationships with the Idah Suite (Johnson, 2006). These granites are poorly exposed, but are occasionally disclosed in isolated sections of creek bed (Figure 2.9). A total of 5 samples were collected and ranged from red garnet-bearing leucogranites to granites (Appendix 1.5). No direct magma-mingling evidence is evident between granitic units. However, a gradational mineralogical boundary, primarily in the reduction of garnet and introduction amphiboles, was observed and served as compositional contacts. There was no evidence of deformation aside from localised quartz veining and hydrous muscovite faulting.
The identification of garnet-bearing assemblages clearly characterise crustal melting (Clarke, 1992), which is discussed further in Chapter 7.7. Mineralogically, the garnet-bearing leucogranites are homogeneous and composed of quartz (~65%), alkali- feldspar (~20%) and plagioclase (10%) that defines granite (Figure 2.9). There are two sample samples that contain less quartz and a minor amount of amphiboles (hornblende), but these are still classified as granites. Apart from varying amounts of well-developed garnet crystals, minor and accessory phases are almost non-existent. However, one isolated patch of interstitial biotite and ilmenite was observed nestled between quartz grains. Texturally, these granites are equigranular, characterised by medium-fine (1-5mm) subhedral quartz and alkali-feldspar grains (Figure 2.9).
Although alkali-feldspar dominates the feldspar mineralogy, there are occurrences of early stage euhedral-subhedral plagioclase grains. Quartz grains appear to form two stages of crystallisation: initial crystallisation of larger subhedral quartz and feldspar grains; followed by smaller interstitial anhedral grains found at the junctions of larger grains. Late stage euhedral garnet crystals are the only accessory phase (Figure 2.9). The crystallisation of these late stage garnet crystals (+ localised muscovite) formed at the expense of hydrous biotite.
33 Figure 2.9: A) Poorly exposed creek beds composed of the Malik Granite. Note the potential compositional variation (presence of garnet). A total of 5 samples were collected here. B) A representation of the garnet-bearing leucogranites (leuco meaning predominately white quartz) obtained at the outcrop. Note the abundance of red garnet crystals and absence of hydrous ferromagnesian minerals. C) A petrographic photograph taken in plane-polarised light of the same granite sample. Note the abundant quartz interrupted by euhedral-subhedral garnet crystals. D) The same petrographic photo taken in cross-polarised light. E)A Plutonic classification scheme modified from De la Roche et al. (1980) of the Malik Granite, which indicates these samples are typically granites. The geochemical and petrogenetic properties of this suite are discussed further in Chapter 7.7. The location of all samples collected and a complementary catalogue of this suite is displayed in Figure 2.10 and Appendix 1.4 respectively.
34 2.4 Petrography Summary and Discussion.
It is clear from the petrological data described in Chapter 2.3, that the Arabian Shield exhibits a combination of classic I-S and A-type granites. These are expressed as hydrous, plagioclase rich granitoids (I-type), garnet- bearing leucogranites (S-type) and aegirine-bearing perthitic alkali-granites (A-type) respectively (Table 2.1). The mineralogy and structural relationships (1: 250, 000 geological maps, Johnson, 2006) of these granitoids provides the opportunity to reconstruct the Arabian Shield without the use of geochronological or geochemical parameters (Figure 2.10).
The Shield is broadly segmented into two halves: western and eastern granitoids separated by the Nabitah Orogenic Belt (Figure 2.10). In general, the western Shield is composed of hydrous I-type suites that display numerous younger cross-cutting intrusions. Conversely, the eastern Shield is dominated by anhydrous perthitic suites, some isolated from and juxtaposed to suture zones, without obvious mafic cumulates. The hydrous ferromagnesian suites confined to the Hijaz terrane are associated with the Yanbu and Bir’ Umq Sutures (Figure 2.10) and are cross-cut by isolated rounded perthitic suites, thus suggest older age I-type suites. The spatial relationship of these intruding I-type suites into suture zones also suggests emplacement during western Shield accretion. Intermediate suites (hydrous mineralogy) display fractionation from MORB like parents (Figure 2.11), whilst felsic endmembers (anhydrous mineralogy) are distinguished by the absence of perthitic mineralogy. Mafic magmatism is strictly confined to the western Shield and produces both hydrous ferromagnesian and perthitic aegirine-bearing granitic suites (Figure 2.10). Obvious fractionation trends are absent in the eastern Shield, which is distinctly dominated by perthitic endmembers.
Arabian Shield amalgamation follows typical syncollisional and post-orogenic magmatic events. The Hijaz and Ad Dawadimi terranes (Figure 2.10) are extraordinary examples of these processes. A closer inspection of their post-orogenic behaviour reveals cross-cutting relationships in the same vicinity as older ferromagnesian samples and syncollisional age suites (Johnson, 2006). Controversy surrounding the generation of aegirine alkali-granites is not necessarily whether they are extension related products (perthitic decompression), but how and why large volumes of mantle can be rapidly emplaced at high crustal levels over a shot period following continental assembly.
35 Figure 2.10: A summary map of the petrography from sampled suites into distinct groups. This highlights the plutonic diversity within the Shield and interestingly shows two distinct perthitic granite types that appear to increase in abundance towards the eastern side. Mafic magmatism is confined to the south western part of the Shield, which is coincidently associated with suture zones. It becomes apparent that the two perthitic granite types are situated in different tectonic settings: within plate suites e.g. Al Bad and Abanat Suites, and those that are associated with suture zones e.g. Kawr Suite, Al Hafoor Suite and Najirah Granite. These two distinguished groups provide an obvious focal point for geochronological and, more importantly, geochemical synthesis. This is explored further in Chapters 3, 4 and 5 respectively.
The Shield exhibits two types of classic perthitic A-type granite (Figure 2.10): those that intrude or are juxtaposed to orogenic sutures and those that are within plate
36 suites isolated from collisional boundaries. The former contain extensive mafic mingling cumulates and fractionate to aegirine perthitic granites (Figure 2.11), whilst the latter are widespread and often associated with economic REE deposits (Johnson, 2006). These also show no evidence of mingling or fractionation from mafic cumulates. The presence of metaluminous, peraluminous and peralkaline units confined to the same geological suite (e.g. Kawr Suite), emplaced into converging continental and oceanic crust (Nabitah Suture, Flowerdew et al. 2013) and exhibit extensive fractionation from mafics cumulates is an interesting, not well documented phenomenon that would be surely overlooked using classic A-type petrographic classification. It is suggested that A-type endmembers, regardless of mafic parents, exhibit similar mineralogy and to simply categorise them all as A-type granite, hence petrogenetic processes, seems inappropriate. Obvious tectonic difference warrants the need for further the geochronological and geochemical separation (Chapter 3, 4 and 5).
Figure 2.11: A summary classification diagram (De la Roche et al., 1980) of 137 samples collected from the Arabian Shield. Blue circles are A-types associated with the Nabitah Suture and appear to fractionate from MORB producing similar endmembers to within plate granitoids (red circles/field, yellow=S-type leucogranite) that exhibit lateral trends from a different tectonic process. Volcanic units (black squares) and hydrous I-types (green circles) follow similar MORB fractionation patterns. The references for Arabian-Nubian granitic fields are displayed in Chapter 2.3.The grey MORB data points are taken from Melson et al. (2002).
37 Table 2.1 part1: A summary of the petrography and rock classification (De la Roche et al., 1980) of 20 sampled Arabian Shield suites. Note these are only the samples with accompanying petrographic photographs described in Chapter 2.3 and Appendix 1. Mineral abbreviations are as follows: aeg=aegirine, alk- fld=alkali-feldspar, ap=apatite, arfv=arfvedsonite, bi=biotite, cpx=clinopyroxene, fl=fluorite, gt=garnet, hast=hastingsite, hbl=hornblende, mag=magnetite, mic=microcline, opx=orthopyroxene, olv=olivine, plag=plagioclase, qtz=quartz, ti=titanate and zirc=zircon.
No. Samples Published Geochronological Geological Map Unit Shield Terrane Rock Type Mineralogy Collected Age (Johnson, 2006) Al Bad Granite Super perthitic alk-fld+qtz+minor plag+bi. Accessory U-Pb in zircon =577Ma Midyan 6 Alkali-Granite Suite (abg) mag+zirc+ap+fl Rb-Sr Isochron=586Ma
Granodiorite/ U-Pb in zircon =715Ma Shufayyah Complex (su) Hijaz 3 plag+qtz+hbl+bi. Accessory mag Tonalite (undocumented) Jar-Salajah Complex and Granodiorite/ U-Pb in zircon =745-695Ma Hijaz 4 qtz+plag+bi+alk-fld + minor mag and hbl Fara' Trondhjemite (js) Granite (unreliable) Rhyolite: alk-fld+qtz+plag (pheoncrysts). Whole rock Rb-Sr Subh Suite (sf) Hijaz 4 Ryholite Groundmass=qtz+alk-fld isochron=659Ma perthitic alk-fld+bi+hbl+minor qtz+plag+mic+ti. Admar Suite (ad) Hijaz 5 Syenite 3 Rb-Sr ages:640-602-583Ma Accessory mag+zirc+ap Diorite/ Age Unknown. Structural Rithmah Complex (rt) Hijaz 4 plag+cpx+hbl+minor olv+opx+mag Gabbro relationships=<600Ma perthitic alk-fld+bi+hbl+minor qtz+plag+olv. Age Unknown. Structural Mardabah Complex (mr) Hijaz 6 Syenite Accessory mag+zirc+ap relationships=<600Ma
Alkali-Granite/ Idah Suite (id) Ha'il 5 perthitic alk-fld+qtz+minor plag+hbl+bi+hast U-Pb in zircon=620-615Ma Syenogranite Abanat Suite (aa) Ha'il 4 Alkali-Granite perthitic alk-fld+qtz+minor plag+aeg+arfv U-Pb in zircon=585-570Ma
Granite/ U-Pb in zircon=641Ma Najirah Granite (nr) Ad Dawadimi 4 alk-fld+qtz+plag+bi+minor mag Alkali-Granite SHRIMP=576Ma Age Unknown. Structural Malik Granite (kg) Ad Dawadimi 5 Leucogranite qtz+alk-fld+minor plag+gt relationships=620-615Ma 2 units: 605-565Ma and 587- Ar Ruwaydah Suite (ku) Ad Dawadimi 4 Granite alk-fld +qtz+plag+bi+minor mag+hast 585Ma Al Khushaymiyah Suite Quartz- perthitic alk-fld+qtz+plag+hbl+minor Ad Dawadimi 5 U-Pb in zircon=611-595Ma (ky) Monzonite mag+bi+mic+ti+hast
38 Table 2.1 part2: A summary of the mineralogy and petrographic classification (De la Roche et al., 1980) of 20 sampled Arabian Shield suites. Note these are only the samples with accompanying petrographic photographs described in Chapter 2.3 and Appendix 1. Mineral abbreviations are as follows: aeg=aegirine, alk-fld=alkali-feldspar, ap=apatite, arfv=arfvedsonite, bi=biotite, cpx=clinopyroxene, fl=fluorite, gt=garnet, hast=hastingsite, hbl=hornblende, mag=magnetite, mic=microcline, opx=orthopyroxene, olv=olivine, plag=plagioclase, qtz=quartz, ti=titanate and zirc=zircon.
Geological Map Unit Shield Terrane No. Samples Rock Type Mineralogy Published Geochronological Collected Age (Johnson, 2006) Quartz- alk-fld+plag+minor qtz+hbl+mic+bi. Accessory U-Pb in zircon =640-625Ma. Haml Suite (hla) Afif 4 Monzonite mag+zirc+ap Some plutons=<610Ma
Age Unknown. Structural Al Hafoor Suite (ao) Tathlith 8 Alkali-Granite alk-fld+qtz+minor hbl+hast+bi. Accessory mag relationships=Ediacaran
U-Pb in zircon?=817-678Ma Makkah Suiite (dm) Jiddah 3 Granodiorite plag+hbl+bi+minor qtz+mag+ti (poorly constrained)
Gabbro plag+olv+cpx+minor mag qtz+alk-fld+plag+bi+minor mag+hast. Mafic Granite enclave=plag+hbl+cpx U-Pb in zircon=650-605Ma Kawr Suite (kw) Asir 35 perthitic alk-fld+qtz+aeg+minor bi+ti. (poorly constrained) Alkali-Granite Accessory mag+ap perthitic alk-fld+qtz+mic+minor bi. Accessory Alkali-Granite mag+ap. Granitic enclave+qtz+alk- fld+plag+minor hast+bi U-Pb in zircon=640-617Ma Ibn Hasbal Suite (ih) Asir 6 Alkali-Granite mic+qtz+bi+minor plag+hbl+hast (poorly constrained) perthitic alk-fld+qtz+bi+minor plag+hast+ti. Rb-Sr and SHRIMP=630-590Ma Al Hawiyah Suite (hwg) Asir 5 Granite Accessory mag (poorly constrained) perthitic alk-fld+qtz+bi+minor hbl+mic+plag. Wadbah Suite (wb) Asir 4 Alkali-Granite SHRIMP=606Ma Accessory mag+zirc
39 Chapter 3: Arabian Shield Pluton Geochronology; Subtle Changes in a Homogeneous Juvenile Mantle.
3.1 Introduction.
The occurrence of island arc (950->730Ma), syncollision (<730->630Ma), post- collisional (<630->600Ma) and anorogenic (<600Ma) magmatism following continental break up is a well established, albeit under investigated notion within the Arabian Shield (Bentor, 1985; Stoeser and Camp, 1985; Johnson et al. 2011). The tectonic timing and East African Orogen (EAO) significance of these accreted terranes is still a highly debated topic (Stern and Johnson, 2010). Nevertheless, the amalgamations of tectonic plates are terminated with the initiation of anorogenic magmatism. This switch from collisional to extensional environments defines a convenient geological marker to provide the minimum stitching age of accretion. Many sampled syncollisional- anorogenic suites (Chapter 2) have limited, poorly constrained data or are determined from structural relationships. This provides the window of opportunity to define through U-Pb geochronology, the tectonic relationships between neighbouring terranes.
The Arabian Shield is consistently referred to as the largest exposure of juvenile continental crust on Earth and its enriched or depleted mantle affinity is still debated (Stein and Goldstein, 1996; Stoeser and Frost, 2006; Be’eri-Shlevin et al., 2010). It is agreed that with the exception of the outer rims, crustal reworking is a foreign concept beneath the Arabian Shield, which exclusively yields juvenile mantle. Discrete terranes overprinted by magmatic cycles provide the ideal setting to discriminate crustal signatures and melt juvenility using zircon hafnium isotopes (Griffin et al., 2000; Scherer et al., 2001; Scherer et al., 2007; Kinny and Maas, 2003; Woodhead et al., 2004; Kemp et al., 2007). Similar studies from Africa, Australia, Asia, Europe, North and South America contain extensive Hf isotopic data sets (Belousova et al., 2010).
This section presents Hf isotopes from 18 U-Pb dated granitoids and establishes a reliable dataset from which implications for mantle juvenility can be drawn. Emphasis is placed on subtle differences between island arc, syncollisional, post-tectonic and anorogenic magmatism and isotopic changes beneath the Nabitah Belt.
40 3.2 U-Pb Geochronology.
From the 137 samples collected from the Arabian Shield (Chapter 2.2), 18 individual granitic suites covering 8 discrete terranes were selected for U-Pb zircon analysis. A total of 452 zircon grains were analysed by LA-ICPMS producing 4 tightly constrained individual magmatic events (Chapter 3.2.2). The U-Pb dating method is displayed in Appendix a1. There is also extensive and high quality geochronological data bases for the Arabian Shield in which the information in this study is obtained. The references for this include: Kennedy et al. (2004), Kennedy et al. (2005), Kennedy et al. (2010a), Kennedy et al. (2010b), Kennedy et al. (2011) and Johnson and Kattan (2007). Much of this data is summarised in Johnson et al. (2011).
3.2.1a Makkah Suite (dm): Gabbro-Diorite.
This mafic suite (Chapter 2.3.1) consists of the Milh and Sharqh Complexes forming the Sarawat Mountains spread across the northern part of the Asir terrane (Figure 8.3). Units are slightly metamorphosed and poorly constrained at 817-687Ma, but have been classified as Tonian based on geochronological data from an identical suite in the neighbouring Nubian Shield (Johnson, 2006). However, new data U-Pb from Kennedy et al. (2011) presents a crystallisation age of 859±1Ma. U-Pb analyses from the Makkah Suite are summarised in Chapter 3.2.2.
The Makkah Suite gabbro-diorite contains various zircon morphologies within sample dm01a (Figure 3.1 and Appendix 3). Some zircons are yellow-brown stubby euhedral prisms ~ 50-100µm in length. These are a mixture of partly recrystallised and distinct core and rim type grains. Primary magmatic zoning is almost non-existent, but some grains contain slight overgrowth zoning towards the rims (Figure 3.1). Numerous grains have complex cores, but still retain a prismatic shape towards the rim. Most stubby prisms appear to be S13-S15 types corresponding with a temperature of ~7500C (Pupin, 1980). However, there are occurrences of diamond shaped R2 zircons (~7000C).
41 Another zircon type is yellow elongate prisms ~100-300µm in length. This group shows very little recrystallisation or overgrowths in grains. The needle like grains illustrate a ‘prison uniform’ type zoning with alternating black and white stripes (Figure 3.1 and Appendix 3). There is no significant difference in analyses between cores and rims. Most grains convey dark cores as elongate slivers, bounded by equally thick white rims. By contrast, some grains appear as predominantly dark cores with slivers of white rims, slightly thicker at the prism ends. Only two elongate grains display ‘embryo like’ zircon attachments, which appear as secondary overgrowths. Overall, Group 2 grains contain distinct primary magmatic zoning with morphologies corresponding with G1-P1 (~600-6500C) types (Pupin, 1980). However, there is the rare occurrence of P4 (~8000C) zircons.
Figure 3.1: A) A concordia plot illustrating the crystallisation age of 842.6Ma constrained from 38 analyses, 36 of which are individual grains (Appendix 2, Table 1). The weighted average values (1 σ error) have been numerically rearranged in descending order to highlight the minimum and maximum values. Raw isotope age data was processed using Glitter software (Van Achterbergh et al., 2001) and conveyed using the Isoplot macro (Ludwig, 2000). B) A representation of the 3 zircon morphologies found in sample dm01a (Appendix 3, Figure A3.1). The calculated initial ɛHf (at U-Pb age) from Hf isotope analysis is also provided and described in Chapter 3.3.
42 Other zircons are yellow elongate prisms ~200-400µm in length. These are similar to those described above, but completely lack primary zoning (Figure 3.1 and Appendix 3) apart from a few grains exhibiting overprinting from the rim. This has left corners of grains illustrating prismatic shapes. All analyses are very concordant and show no significance between overgrowths and rims. It is difficult to distinguish morphologies, but few remaining shapes suggest P1-R1 (~6500C) zircons.
38 analyses from 36 individual zircon grains yielded a U-Pb concordia age of 842.6±6.7Ma (MSWD=1.5) and a 206Pb-238U weighted average age of 845.6±4.9Ma (MSWD=1.6). These zircons exhibited no Pb loss or inheritance and produce a tight concordance (Figure 3.1). The mean concordancy is 99% with only 2 out of 38 grains showing >10% discordance. These are 82% and 87% and display elevated 207Pb/206Pb ages of 1033Ma and 958Ma respectively. However, these analyses are still used in the mean calculation because they both contain a 206Pb-238U age of 834-843Ma and are within 1σ error of the suite mean age.
Overall, this suite produced an age of 846Ma (859±1Ma -Kennedy et al., 2011) that is consistent with island arc magmatism (<950->730Ma). Multiple zircon morphologies are identified and display no evidence of inheritance or metamorphism. The suite age is interpreted to be the first magmatic phase in the Arabian Shield after ~1200-950Ma African rifting and is discussed further in Chapter 8.2.
3.2.1b Shufayyah Complex (su): Tonalite.
This discordant tonalitic suite is spread over the southern Hijaz terrane between the Yanbu and B’ir Umq Sutures (Figure 8.3). Plutons are emplaced into the already folded rocks of the Birak (805Ma) and Al Ays Groups (745-700Ma). The suite has an undocumented age of 715Ma from U-Pb in zircon (Johnson, 2006). U-Pb analyses from the Shufayyah Complex are summarised in Chapter 3.2.2.
The Shufayyah Complex tonalite contains distinguished zircon morphologies within sample su215 (Figure 3.2 and Appendix 3). Some zircons are yellow stubby
43 euhedral pyramids ~<100µm in length. These exhibit faint core and rim zoning and are homogeneously bright. Some grains contain a slightly darker core, but no grains display a tendency for dimming towards the rims. Some zircons illustrate fine laminar zoning interrupted by a thicker overgrowth towards the rims. There is no age distinction between the cores and rims. Zircon morphology is reasonably distinctive despite the bright nature. Most grains exhibit L2-L4 and possibly G2 characteristics, which corresponds with ~6500C (Pupin, 1980).
Another zircon variety is yellow-pink stubby euhedral pyramids ~50µm in size. This group contains the most abundant amount of zircons and are similar to those described above, but exhibit fine laminations confined to internal zones. These become increasingly thicker to almost non-existent towards the rims (Figure 3.2). Very few grains display darker cores with most appearing as homogeneous grey cores with little change in brightness. Almost all zircons retain their crystallised shape with no recrystallisation apparent. A select few show overgrowths towards the rims. Numerous smaller grains display equant octagon style pyramidal shapes, which appear to correlate with AB2-AB4 types with a low temperature of ~5500C (Pupin, 1980). Some larger grains display slightly hotter (~6500C) L2-L3-S2-S3 characteristics.
The last zircon type is colourless-brown elongate prisms ~100-150µm in length. These are the only elongate needle like zircons found in this suite and display simple compositional zoning (Figure 3.2). The images display a mixture of brighter and darker cores. The zircons either stay homogeneously bright or show a tendency for brighter rims. Overall, zoning is medium-fine, but one bright grain shows a prominent thick outer zone with a small core. Recrystallisation is non-existent, but overgrowths are observed, particularly towards the rims of smaller grains. Most grains exhibit P1 (~6500C) characteristics, but one grain is an S14 (~7500C) zircon (Pupin, 1980).
47 individual zircon analyses yielded a U-Pb concordia age of 715.8±3.2Ma (MSWD=1.09) and a 206Pb-238U weighted average age of 715.4±3.6Ma (MSWD=1.2). These zircons exhibited no Pb loss or inheritance and produce a tight concordancy (Figure 3.2). The mean concordancy is 101% with only 8 out of 47 analyses showing >10% discordance. The lowest and highest values are 88% and 119% respectively.
44 These are consistent with fluctuating 207Pb/206Pb, but are used in the mean calculation because they have 206Pb-238U ages within 1σ error of the mean age.
Overall, this suite produced an age of 715Ma consistent with syncollisional magmatism (<730->630Ma) constrained by 3 distinguished zircon morphologies. The emplacement of this suite in the vicinity of the B’ir Umq Suture marks the first syncollisional magma phases associated with the Hijaz-Asir microplate accretion. This helps to constrain further the B’ir Umq Suture age of ~700-680Ma (Hargrove, 2006) and is discussed further in Chapter 8.3.
Figure 3.2: A) A concordia plot illustrating the crystallisation age of 715.8Ma constrained from 47 individual grains (Appendix 2, Table 2). The weighted average values (1 σ error) have been numerically rearranged in descending order to highlight the minimum and maximum values. Raw isotope age data was processed using Glitter software (Van Achterbergh et al., 2001) and conveyed using the Isoplot macro (Ludwig, 2000). B) A representation of the 3 zircon morphologies found in sample su215 (Appendix 3, Figure A3.2). The calculated initial ɛHf (at U-Pb age) from Hf isotope analysis is also provided and described in Chapter 3.3.
45 3.2.1c Jar-Salajah Complex and Fara’ Trondhjemite (js): Granodiorite.
This suite consists of multiple intrusions spread over both the Midyan and Hijaz terranes, cross-cutting the Yanbu Suture in the northwestern part of the Shield (Figure 8.3). These units have been poorly constrained by U-Pb in zircons at 745-695Ma (Johnson, 2006) and are emplaced into the already deformed volcanics of the Al Ays (745-700Ma) and Zaam (760-710Ma) Groups. U-Pb analyses from the Jar-Salajah Complex are summarised in Chapter 3.2.2.
The Jar-Salajah Complex granodiorite contains various zircon morphologies within sample js202 (Figure 3.3 and Appendix 3). Some zircons are brown stubby euhedral pyramids ~<100µm in length. These exhibit a mixture of distinct core and rim zoning and homogeneous grey laminated oscillatory zoning, but all produce medium CL responses. Some grains contain a slightly darker core, but no grains display a tendency for dimming towards the rims. Although most grains illustrate homogeneous zoning from core to rim, occasional grains are interrupted with overgrowths towards the rims. Zircon morphology is reasonably distinctive with most grains exhibiting pyramidal AB2-AB4 (~5500C) characteristics (Pupin, 1980). One grain appears to be a diamond shaped G3 (~6000C) type, while 2 grains display S3 (~6500C) overgrowths with an indeterminate core.
Other zircon types are yellow elongate prisms ~100-200µm in length. These are the most abundant zircons and exhibit fine oscillatory zoning with distinct core and rims (Figure 3.3). Many grains appear to have thick black and/or white banded cores surrounded by very fine zoning towards the rims. There was insignificant age difference between core and rims. A closer inspection of the thicker cores surrounded by finer zoning, reveals textural overprinting. This morphology appears to be black elongate squarish cores exhibiting P4 (~8000C) type characteristics, but are overprinted by S12- S13 (~7500C) zircons (Pupin, 1980). Few grains show S8-S10 (~7000C) type structures with one elongate diamond R1 (~6500C) shaped zircon. The grain illustrated in Figure 3.3 corresponds with the hottest temperature of ~8500C displaying an octagon shaped core (S24 zircon type).
46 Figure 3.3: A) A concordia plot illustrating the crystallisation age of 705.9Ma constrained from 29 analyses, 27 of which are individual grains (Appendix 2, Table 3). The weighted average values (1 σ error) have been numerically rearranged in descending order to highlight the minimum and maximum values. Raw isotope age data was processed using Glitter software (Van Achterbergh et al., 2001) and conveyed using the Isoplot macro (Ludwig, 2000). B) A representation of the 3 zircon morphologies found in sample js202 (Appendix 3, Figure A3.3). The calculated initial ɛHf (at U-Pb age) from Hf isotope analysis is also provided and described in Chapter 3.3.
Another zircon type is yellow stubby euhedral pyramids ~<100µm in length (Figure 3.3). Apart from the colour, these are vey similar to the first zircons described. These exhibit a medium CL response with homogeneous fine grey laminations. This is strictly confined to the outer rims of the zircon. Some grains contain black complex
47 cores synonymous with 204Pb and were avoided for analysis. No overgrowths are apparent with most morphology AB2-AB4 (~5500C) zircon types (Pupin, 1980).
29 analyses from 28 individual zircon grains yielded a U-Pb concordia age of 705.9±7Ma (MSWD=1.4) and a 206Pb-238U weighted average age of 693.2±6.3Ma (MSWD=3.5). These zircons exhibited no Pb loss or inheritance and produce a spread of data with tight concordance (Figure 3.3). The mean concordancy is 96% with only 5 out of 29 analyses showing >10% discordance. These lie between 80-90% and are consistent with fluctuating 207Pb/206Pb, but are used in the mean calculation because they have 206Pb-238U ages within 1σ error of the mean age. Overall, this suite produced an age of 694Ma consistent with syncollisional magmatism (<730->630Ma) constrained by distinguished 3 zircon morphologies. This cross-cuts the Yanbu Suture, constraining both the suite age and final Midyan-Hijaz accretion. The tectonic significance of this suite is discussed in Chapter 8.3.
3.2.1d Subh Suite (sf): Rhyolite.
The Subh Suite (Appendix 1.3) is locally composed of two complexes confined to the southern Hijaz terrane (Figure 8.3). It cross-cuts older deformed units such Birak Group (805Ma) and the Milhah Formation (715Ma) and also intrudes the Shufayyah Complex (715Ma). The crystallisation age of this suite is unknown, but has been given an unreliable Rb-Sr whole rock date of 659Ma (Johnson, 2006) and 696Ma from 3 discordant zircons (Aleinikoff and Stoeser, 1989). U-Pb analyses from the Subh Suite are summarised in Chapter 3.2.2.
Subh Suite rhyolite zircons vary from colourless elongate euhedral prisms ~100- 200µm in length to pink-brown stubby euhedral prisms ~50-10µm in length. Overall, the elongate grains display medium to very fine oscillatory zoning with generally bright CL responses (Figure 3.4 and Appendix 3). Some larger elongate grains, although bright, generally lack zoning. By contrast, the stubby prisms are very dark with slightly thicker zoning. There appears to be a mix of bright and darker cores, but all have a tendency for dimming towards the rims. Numerous elongate grains show overgrowths
48 that change the morphology of the rims. In general, the stubby grains exhibit a S7-S10 (~7000C) structure, while the elongate grains show P1-P2 (~750-7000C) characteristics (Pupin, 1980). A few examples of diamond shaped R2-R1 (~750-7000C) types were also observed.
Figure 3.4: A) A concordia plot illustrating the tight concordance of 22 individual grain analyses yielding a crystallisation age of 699.1Ma (Appendix 2, Table 4). The weighted average values (1 σ error) have been numerically rearranged in descending order to highlight the minimum and maximum values. Raw isotope age data was processed using Glitter software (Van Achterbergh et al., 2001) and conveyed using the Isoplot macro (Ludwig, 2000). B) A finely oscillatory zoned zircon image representing a typical zircon type analysed from the Subh Suite (Appendix 3, Figure A3.4). The calculated initial ɛHf (at U-Pb age) from Hf isotope analysis is also provided and described in Chapter 3.3.
49 22 individual zircon analyses yielded a U-Pb concordia age of 699.1±5.8Ma (MSWD=0.21) and a 206Pb-238U weighted average age of 698.7±5.5Ma (MSWD=0.21). These zircons exhibited no Pb loss or inheritance and the tight concordancy is interpreted to be the crystallisation age of the suite (Figure 3.4). The mean concordancy is 98 % with only 2 of 22 displaying a >10% discordance. These 2 grains at 111% record slightly lower 207Pb/206Pb ages of 632Ma, but are still used in the mean calculation because the 206Pb-238U age is within 1σ error of the mean age of the suite. All raw data are presented in Appendix 2, Table 4. Overall, this suite age of 699Ma is consistent with syncollisional magmatism (<730->630Ma). The tectonic implications are discussed further in Chapter 8.3.
3.2.1e Kawr Suite (kw): Granodiorite
The undeformed intrusives of the Kawr Suite (Chapter 2.3.3) are emplaced into south eastern sections of the Nabitah Orogenic Belt in the Asir terrane (Figure 8.3). Zircons in this suite have been directly dated (U-Pb) at 650-620Ma.However, localised plutons have been documented at 605Ma (Johnson, 2006). U-Pb analyses from the Kawr Suite are summarised in Chapter 3.2.2.
Kawr Suite granodiorite contains multiple zircon morphologies within the sample kw42 (Figure 3.5 and Appendix 3). Some zircons are yellow stubby euhedral prisms ~<100µm in length. These exhibit distinct dark cores surrounded by medium- fine oscillatory zoning. Most cores are thickly walled, enclosed by thinner oscillatory zoned rims. With the exception of one grain, the CL response is homogeneous from core to rim with a tendency for slightly darker rims. One zircon contains a bright band in the outer zones of the grain. Several grains appear as overgrowths towards the rims. Zircon morphology is reasonably distinctive with most grains exhibiting S18-S19 (~8000C) characteristics (Pupin, 1980). One unanalysed grain contains a distinctive octagon shaped core, possibly correlating to a J4 (~9000C) zircon type.
Another zircon variety has brown-pink elongate euhedral prisms ~100-200µm in length. These are the most abundant zircons and exhibit medium-fine oscillatory
50 Figure 3.5: A) A concordia plot illustrating the crystallisation age of 618Ma constrained from 26 individual grains (Appendix 2, Table 5). The weighted average values (1 σ error) have been numerically rearranged in descending order to highlight the minimum and maximum values. Raw isotope age data was processed using Glitter software (Van Achterbergh et al., 2001) and conveyed using the Isoplot macro (Ludwig, 2000). B) A representation of the 3 zircon morphologies found in sample kw42 (Appendix 3, Figure A3.5). The calculated initial ɛHf (at U-Pb age) from Hf isotope analysis is also provided and described in Chapter 3.3. laminations confined to the outer zones (Figure 3.5). There is a distinct difference between thickly walled cores and finely laminated rims. There is a tendency for darker cores, but few grains display bright internal zones. No grains show a preference for dark or bright rims, but rather display a homogeneous grey response from core to rim.
51 Almost all zircons retain their crystallised shape with no recrystallisation apparent, but often display fine oscillatory overgrowths towards the rims. However, these appear not to change in morphology, but rather just cyclically repeat the same structure. This is possibly related to a change in pressure rather than temperature. There is a mixture of zircon morphologies within this group. These range from S24 (~8500C) to S17-S19 (~8000C) and finally to S13-S14-P3 (~7500C) zircon types (Pupin, 1980).
Other zircons are colourless-yellow elongate prisms ~100-20µm in length. These are similar to those described above, but display very bright CL responses. In general, zircons have very fine oscillatory zoning, but in some cases are too bright to distinguish distinct cores and rims. In contrast, some grains lack complex zonation and display a homogeneous thick grey core surrounded by thinner bright rims (Figure 3.5). There appears to be a tendency for brighter rims, but one grain contains a very bright core with darker rims. Recrystallisation and overgrowths appear non-existent. There is again a mixture of morphologies ranging from S23-S24-P5 (~8500C) to S19 (~8000C) and finally P3 (~7500C) zircon types (Pupin, 1980). One grain also shows an octagon style core surrounded by a prismatic rim, which possibly correlates with a J4 (~9000C) structure.
26 individual zircon grain analyses yielded a U-Pb concordia age of 618±7.1Ma (MSWD=1.9) and a 206Pb-238U weighted average age of 611.7±6.5Ma (MSWD=2.4). These zircons exhibited no Pb loss or inheritance and produce a spread of data with tight concordance (Figure 3.5). The mean concordancy is 95% with 12 out of 26 analyses showing >10% discordance. The lowest and highest values are 81% and 116% respectively. These are consistent with fluctuating 207Pb/206Pb, but are used in the mean calculation because they have 206Pb-238U ages within 1σ error of the mean age. Overall, this suite produced an age of 612Ma, consistent with post-tectonic magmatism (<636- >600Ma) constrained by 3 distinguished zircon morphologies. These intrusives intrude the Nabitah Orogenic Belt after the final amalgamation of the southern Asir and Afif plates (~640Ma). This unit is a definite marker of the minimum stitching age in this part of the Shield. The tectonic significance is discussed further in Chapter 8.4.
52 3.2.1f Al Hafoor Suite (ao): Alkali-Granite
The Al Hafoor undeformed mafic-felsic units (Appendix 1.6) consist of multiple intrusions juxtaposed to the Nabitah Orogenic Belt in the Tathlith terrane south of the Ruwah Fault Zone (Figure 8.3). These intrusives have an unknown age, but post-date the Bani Ghayy Group (630-620Ma) volcanic sediments and have been classified as Ediacaran from structural relationships (Johnson, 2006). U-Pb analyses from the Al Hafoor Suite are summarised in Chapter 3.2.2.
Alkali-granite from the Al Hafoor Suite contains zircons that are predominately yellow-brown stubby euhedral prisms ~50-100µm. However, there are few clear elongate prisms up to ~150µm. Overall, images are homogeneously grey displaying fine oscillatory zoning with a generally low-medium CL response (Figure 3.6 and Appendix 3). Some elongate grains exhibit more diversity and contain darker needle like cores surrounded by thicker slightly brighter rims. There is no apparent tendency for brighter or darker rims, but rather homogeneously grey from core to rim. One grain does experience a dimming towards the outer zones. There is no obvious recrystallisation, but overgrowths towards the outer zones of some grains are observed. Overall, stubby prism morphology is predominantly S3-S5 (~6500C), whilst elongate grains are slightly hotter P2 (~7000C) type (Pupin, 1980). There is also one octagon shaped AB3-AB4 (~5500C) zircon. Some larger grains also convey S13-S14 (~7500C) cores overgrown at the rims by S4-S5 (~6500C) shapes.
16 individual zircon analyses yielded a U-Pb concordia age of 639.6±7Ma (MSWD=0.79) and a 206Pb-238U weighted average age of 636±4Ma (MSWD=0.81). These zircons exhibited no Pb loss or inheritance, but convey a reasonably poor concordance (Figure 3.6). The mean concordancy is 88 % with only 5 of 16 displaying a <10% discordance. The lowest value recorded is 78% with the remaining 11 analyses between 80-90%. All grains have slightly elevated 207Pb/206Pb ages of ~700-750Ma, which poses difficulties in obtaining a tight concordance. However, all 16 analyses are still used in the mean calculation because the 206Pb-238U age is within 1σ error of the mean age of the suite. Raw data are presented in Appendix 2, Table 6. Overall, the 636Ma age defines post-tectonic magmatism (<636->600Ma) consistent with Nabitah Suture termination (~680-640Ma) and is discussed further in Chapter 8.4.
53 Figure 3.6: A) A concordia plot illustrating the crystallisation age of 639.6Ma constrained from 16 individual grain analyses (Appendix 2, Table 6). The weighted average values (1 σ error) have been numerically rearranged in descending order to highlight the minimum and maximum values. Raw isotope age data was processed using Glitter software (Van Achterbergh et al., 2001) and conveyed using the Isoplot macro (Ludwig, 2000). B) A finely oscillatory zoned zircon image representing a typical zircon type analysed from the Al Hafoor Suite (Appendix 3, Figure A3.6). The calculated initial ɛHf (at U-Pb age) from Hf isotope analysis is also provided and described in Chapter 3.3.
54 3.2.1g Najirah Granite (nr): Granite.
This unit consists of multiple batholiths straddling the border between the Afif and Ad Dawadimi terranes in the eastern part of the Shield (Figure 8.3). The undeformed perthitic suite (Appendix 1.5) is juxtaposed and cross-cuts the Halaban Suture between the Afif and Ad Dawadimi microplates. Localised units have been dated (U-Pb in zircons) at 575Ma (Johnson, 2006) and is itself intruded by the Idah (607Ma) and Ar Ruwaydah (612Ma) Suites. U-Pb analyses from the Najirah Granite are summarised in Chapter 3.2.2.
The Najirah Granite contains various zircon morphologies within sample nr120 (Appendix 3, Figure A3.7). The first type are yellow stubby euhedral prisms <100µm in length. Many grains exhibit faint core and rim zoning and are homogeneously dark with both dull cores and rims. In contrast, some are bight from core to rim and show medium oscillatory zoning (Figure 3.7). Multiple grains contain xenocrystic style grey cores, but no age difference was recorded. Zircon morphology is relatively distinct with grains showing S13-S15 (~7500C) and S8-S10 (~7000C) characteristics (Pupin, 1980).
Another zircon morphology is pink elongate euhedral prisms ~150-250µm in length. This group contains the most abundant amount of zircons. These grains contain medium-fine compositional oscillatory zoning, arguably the best observed from any suite (Figure 3.7). These illustrate distinct dark cores with intermittent brighter zones before a dimming towards the rims. Th dark cores vary in shape from needle like slivers to thicker octagon prismatic shapes. Several grain cores display small <50µm prismatic overgrowths cross-cutting the oscillatory zoning. Many grains contain simple zoned cores with fine oscillatory overgrowths towards the rims. No recrystallisation is apparent and morphology is distinctive. Zircon grains predominantly exhibit S23-S24 (~8500C) to S18-S19 (~8000C) morphologies (Pupin, 1980), but there are some examples of P4-P3 (~800-7500C) characteristics and one unanalysed possible J4 (~9000C) shaped zircon.
The last zircon types are colourless-yellow elongate prisms ~100-300µm in length. These are the only elongate needle like zircons found in this suite and display simple compositional zoning (Figure 3.7). The images display thick homogeneous
55 bright cores with a tendency for dimming towards the rims. The bright cores dominant the zircon composing ~80% of the grain. Only the outer rims contain visible fine oscillatory zoning and distinguishable prismatic shapes. There appears to be no recrystallisation or overgrowths. Zircon morphology is defined as the P4-P2 (~800- 7000C) types (Pupin, 1980).
Figure 3.7: A) A concordia plot illustrating the crystallisation age of 616Ma constrained from 20 analyses, 19 of which are individual grains (Appendix 2, Table 7). The weighted average values (1 σ error) have been numerically rearranged in descending order to highlight the minimum and maximum values. Raw isotope age data was processed using Glitter software (Van Achterbergh et al., 2001) and conveyed using the Isoplot macro (Ludwig, 2000). B) A representation of the 3 zircon morphologies found in sample nr120 (Appendix 3, Figure A3.7). The calculated initial ɛHf (at U-Pb age) from Hf isotope analysis is also provided and described in Chapter 3.3.
56 20 analyses from 19 individual zircon grains yielded a U-Pb concordia age of 616±9.5Ma (MSWD=2.1) and a 206Pb-238U weighted average age of 607±7.9Ma (MSWD=2.9). These zircons exhibited no Pb loss or inheritance and produce a spread of data with fair concordance (Figure 3.7). The mean concordancy is 89% with 12 of 20 analyses showing <10% discordance. Of the remaining 8 analyses, the lowest value recorded is 65% and like all >10% discordant grains, is associated with elevated 207Pb/206Pb ages. However, all 20 analyses are used in the mean calculation because they have 206Pb-238U ages within 1σ error of the mean age. Overall, this suite produced an age of 607Ma consistent with post-tectonic magmatism (<636->500Ma) constrained by 3 distinguished zircon morphologies. This age appears to provide the minimum stitching age between the Afif and Ad Dawadimi microplates. The tectonic significance of this age is discussed further in Chapter 8.4.
3.2.1h Wadbah Suite (wb): Alkali-Granite.
The Wadbah Suite undeformed intrusives (Appendix 1.8) cross-cut the Nabitah Orogenic Belt, south of the Ruwah Fault Zone, in the southern part of the Asir terrane (Figure 8.3). This suite has been directly using SHRIMP at 606Ma (Johnson, 2006). U- Pb analyses from the Wadbah Suite are summarised in Chapter 3.2.2.
This alkali-granite contains various zircon morphologies found within sample wb65 (Figure 3.8 and Appendix 3). The first observed are zircons that are yellow stubby euhedral prisms <100µm in length. Cores and rims are faintly discriminated, but most display homogeneous grey fine oscillatory zoning. There is no apparent recrystallisation, but many grains contain overgrowths towards the rims. Many of the core morphologies remain indistinguishable, but the rims can be determined. This morphology is predominantly S18-S19 (~8000C) and S15 (~7500C) characteristics and one diamond shaped R3 (~7500C) zircon is observed (Pupin, 1980).
Another zircon variety is yellow-pink elongate euhedral prisms ~100-250µm in length. This group contains the most abundant amount of zircons. These zircons are well zoned displaying fine homogeneous grey oscillatory zoning. The needle like
57 prismatic grains have a tendency for darker cores with a dimming towards the rims (Figure 3.8). Many grains exhibit prismatic cores overgrown by elongate octagons towards the rims. Interestingly, this also occurs in reverse with octagon shaped cores overprinted by prismatic rims. This is thought to resemble fluctuations in chamber temperatures. Overall, morphology varies from S19-S20-P4-R4 (~8000C) to S15-P3 (~7500C) zircon characteristics (Pupin, 1980).
Figure 3.8: A) A concordia plot illustrating the crystallisation age of 617.9Ma constrained from 26 individual grains (Appendix 2, Table 8). The weighted average values (1 σ error) have been numerically rearranged in descending order to highlight the minimum and maximum values. Raw isotope age data was processed using Glitter software (Van Achterbergh et al., 2001) and conveyed using the Isoplot macro (Ludwig, 2000). B) A representation of the 3 zircon morphologies found in sample wb65 (Appendix 3, Figure A3.8). The calculated initial ɛHf (at U-Pb age) from Hf isotope analysis is also provided and described in Chapter 3.3.
58 Another zircon morphology observed is colourless-brown elongate prisms ~100-200µm in length. The images display a bright CL response with a tendency for dimming towards the rims (Figure 3.8). Overall, the zoning is medium-fine homogeneous grey oscillatory zoning. Recrystallisation is non-existent and overgrowths are observed occurring early on in the cores growth. Initial core morphology is too difficult to distinguish, but the outer zones exhibit S14-S15-P3 (~7500C) characteristics (Pupin, 1980).
26 individual zircon grain analyses yielded a U-Pb concordia age of 617.9±5.4Ma (MSWD=1.9) and a 206Pb-238U weighted average age of 615.9±4.9Ma (MSWD=2). These zircons exhibited no Pb loss or inheritance and produce a spread of data with tight concordance (Figure 3.8). The mean concordancy is 98% with only 6 out of 26 analyses showing >10% discordance. The lowest and highest values are 81% and 111% respectively. These are consistent with fluctuating 207Pb/206Pb, but are used in the mean calculation because they have 206Pb-238U ages within 1σ error of the mean age. Overall, this suite produced an age of 616Ma consistent with post-tectonic magmatism (<636->600Ma) constrained by 3 distinguished zircon morphologies. These alkali-granites intrude the Nabitah Orogenic Belt in which accretion ceased at ~640Ma (Johnson, 2006). The tectonic significance of this suite is discussed in Chapter 8.4.
3.2.1i Ibn Hashbal Suite (ih): Alkali-Granite.
The Ibn Hashbal Suite (Appendix 1.8) forms a widespread A-type granitic group intruding the Nabitah Orogenic Belt in the south eastern corner of the Asir terrane (Figure 8.3). This unit comprises multiple ring complexes that are lithologically categorised as one. These have been individually dated (U-Pb in zircons) to provide a broad suite age of 640-615Ma (Johnson, 2006). U-Pb analyses from the Ibn Hashbal Suite are summarised in Chapter 3.2.2.
Zircons from the Ibn Hashbal Suite are predominantly yellow-brown elongate euhedral prisms ~150-300µm in length. Overall, images display dark cores and medium to fine oscillatory zoned rims with a bright CL response (Figure 3.9 and Appendix 3). Multiple grains exhibit no distinct zones, but rather a continuous, bright, finely
59 laminated response. In general, there is no tendency for dimming towards the rims. Some convey an almost entirely dark zone with a fine bright rim. There appears to be no recrystallising of rims, but some grains exhibit patchy overgrowths.
Figure 3.9: A) A concordia plot illustrating the tightly constrained crystallisation age of 621.3Ma from 19 analyses, 15 of which are individual grains (Appendix 2, Table 9). The weighted average values (1 σ error) have been numerically rearranged in descending order to highlight the minimum and maximum values. Raw isotope age data was processed using Glitter software (Van Achterbergh et al., 2001) and conveyed using the Isoplot macro (Ludwig, 2000). B) A finely oscillatory zoned zircon image representing a typical zircon type analysed from the Ibn Hashbal Suite (Appendix 3, Figure A3.9). The calculated initial ɛHf (at U-Pb age) from Hf isotope analysis is also provided and described in Chapter 3.3.
Most elongate zircons are classic P1-P2 types corresponding with a temperature of ~650-7000C (Pupin, 1980). However, there are some blocky prismatic grains that appear to correspond with S19-S20 types and higher temperatures of ~8000C. Despite
60 minor differences in the primary oscillatory zoning, there was no significant age difference between cores and rims. The inner zones were targeted wherever possible because they are assumed to represent the crystallisation age of the zircon.
19 analyses from 15 individual zircon grains yielded a U-Pb concordia age of 621.3±7.1Ma (MSWD=0.68) and a 206Pb-238U weighted average age of 617.6±5.2Ma (MSWD=0.76). These zircons exhibited no Pb loss or inheritance and constrain a tight concordance (Figure 3.9), which is interpreted as the suite crystallisation age. The mean concordancy is 91%, but two grains at 71% and 117% are recorded. These display 207Pb/206Pb ages of ~848Ma and ~525Ma respectively. However, they are used in the mean calculation because both contain a 206Pb-238U age of 605 and 616Ma and are within 1σ error from the suite mean age. 10 of 19 analyses recorded >10% discordance and range from 71-117%. All raw data are presented in Appendix 2, Table 9. Overall, this 618Ma age is consistent with post-tectonic magmatism (<636->600Ma). The tectonic significance is discussed further in Chapter 8.4.
3.2.1j Ar Ruwaydah Suite (ku): Granite.
The undeformed granites of the Ar Ruwaydah Suite (Appendix 1.5) are confined to Ad Dawadimi terrane straddling the Halaban Suture in the eastern part of the Shield (Figure 8.3). Locally, they are separated into the Khurs and Arwa Granites conveying two discrete granite types and ages. According to Johnson (2006) the white leucocratic Khurs granite yields two zircon ages ranging from 605-598Ma and 579- 565Ma (SHRIMP). The pink Arwa microgranite is associated with an unreliable Rb-Sr isochron of 587Ma and a SHRIMP age of 575Ma. U-Pb analyses from the Ar Ruwaydah Suite are summarised in Chapter 3.2.2.
Zircons from the Ar Ruwaydah Suite are predominantly yellow-brown stubby euhedral prisms ~50-100µm in length. However, colourless-pink slightly more elongate prisms ~100-150µm also occur. Overall, stubby prism images display dark cores, followed by medium-fine oscillatory zoning and finally thick dark rims (Appendix 3, Figure A3.10). Some of these exhibit patchy recrystallised cores commonly associated with dark inclusions. A Few grains are completely dark with only minor grey patches.
61 Figure 3.10: A) A concordia plot illustrating the constrained crystallisation age of 610.7Ma from 20 individual grain analyses (Appendix 2, Table 10). The weighted average values (1 σ error) have been numerically rearranged in descending order to highlight the minimum and maximum values. Raw isotope age data was processed using Glitter software (Van Achterbergh et al., 2001) and conveyed using the Isoplot macro (Ludwig, 2000). B) A finely oscillatory zoned zircon image representing a typical zircon type analysed from the Ar Ruwaydah Suite (Appendix 3, Figure A3.10). The calculated initial ɛHf (at U-Pb age) from Hf isotope analysis is also provided and described in Chapter 3.3.
Typically, the morphology of the stubby prisms is S3-S5 types corresponding with a temperature of ~6500C (Pupin, 1980). By contrast, the slightly more elongate zircons display finely laminated bright images (Figure 3.10). These are homogeneously grey or slightly white and convey no apparent overgrowths or recrystallisation. This is with the exception of one grain, which displays a slight recrystallisation at one end of
62 the zircon. These grains exhibit S10-S14 tendencies that correspond with a temperature of ~7500C (Pupin, 1980).
20 individual zircon grain analyses yielded a U-Pb concordia age of 610.7±5.5Ma (MSWD=1.03) and a 206Pb-238U weighted average age of 612.1±4.9Ma (MSWD=1.12). These zircons exhibited no inheritance, but possibly have experienced minor Pb loss. The mean concordancy is 98%, but two grains at 81% and 118% are recorded. These display 207Pb/206Pb ages of 757Ma and 532Ma respectively. However, these analyses are still used in the mean calculation because both contain a 206Pb-238U age of ~615-630Ma and are within 1σ error from the mean age of the suite. Only 7 of 20 analyses recorded are >10% discordant and range from 80-120%. All raw data are presented in Appendix 2, Table 10. Overall, this suite produced an age of 612Ma consistent with post-tectonic magmatism (<636Ma). The tectonic significance is discussed further in Chapter 8.4.
3.2.1k Haml Suite (hla): Quartz-Monzonite.
This perthitic suite (Appendix 1.7) is a widespread unit, locally composed of multiple intrusions, east of the Nabitah Orogenic Belt in the southern Afif terrane (Figure 8.3). The suite is divided into two distinctive undeformed age groups (U-Pb in zircon): the Samim Complex at 640-625Ma and the Himarah Complex at 610Ma (Johnson, 2006). U-Pb analyses from the Haml Suite are summarised in Chapter 3.2.2.
Zircons from the Haml Suite are predominantly yellow-brown elongate euhedral prisms ~100-200µm in length. Overall, images display medium to fine oscillatory zoning with a homogeneous grey CL response (Figure 3.11 and Appendix 3). Primary magmatic zoning observed in zircons showed no age difference between zones. Multiple grains exhibit no distinct zones, but rather a continuous, bright, finely laminated response. However, in general, there is a tendency to have darker cores with intermittent oscillatory banding, finally followed by dimming towards the rims. Few grains exhibit overgrowths in the cores with primary zoning all but disappeared except for prismatic remnants towards the rims.
63 Figure 3.11: A) A concordia plot illustrating the poorly concordant crystallisation age of 619.3Ma constrained from 15 individual grain analyses (Appendix 2, Table 11). The weighted average values (1 σ error) have been numerically rearranged in descending order to highlight the minimum and maximum values. Raw isotope age data was processed using Glitter software (Van Achterbergh et al., 2001) and conveyed using the Isoplot macro (Ludwig, 2000). B) A finely oscillatory zoned zircon image representing a typical zircon type analysed from the Haml Suite (Appendix 3, Figure A3.11). The calculated initial ɛHf (at U-Pb age) from Hf isotope analysis is also provided and described in Chapter 3.3.
Multiple grains also convey dark thick prismatic cores surrounded by brighter thinner walls. Most elongate grains are S13-S15 zircon types corresponding with a temperature of ~7500C (Pupin, 1980). However, there are some blocky prismatic grains that appear to correspond with higher temperatures of ~8000C and are possibly S19-S20 zircon types. One grain even exhibits S19 type morphology in the core, but the outer zones gradually reform into lower temperature S13 characteristics. This may reflect the rapid ascension of a hot magma chamber into the cooler crust, forcing magma
64 temperatures to decrease. The compositional zoning showed no age differences between cores and rims.
15 individual zircon grains yielded a U-Pb concordia age of 619.3±7.3Ma (MSWD=1.4) and a 206Pb-238U weighted average age of 608.6±8.1Ma (MSWD=2.3). These zircons exhibited no Pb loss or inheritance, but convey a poor concordance (Figure 3.11). The mean concordancy is 88%, just outside <10% discordance. 8 of 15 grains are <10% discordant, whilst the remaining 7 contain slightly elevated 207Pb/206Pb ages ranging from ~700-800Ma. However, these analyses are still used in the mean calculation because they contain a 206Pb-238U age that lie within 1σ error from the mean age of the suite. Despite fluctuations in Pb, all 15 analyses are interpreted to represent the crystallisation age of the suite. All raw data are presented in Appendix 2, Table 11. Overall, this suite produced an age of 609Ma consistent with post-tectonic magmatism (<636->600Ma). This provides the minimum stitching age for the southern part of the Afif terrane and is discussed further in Chapter 8.4.
3.2.1l Kawr Suite (kw): Alkali-Granite.
The undeformed intrusives of the Kawr Suite (Chapter 2.3.3) are emplaced into sections of the Nabitah Orogenic Belt in the south eastern Asir terrane (Figure 8.3). This suite has been directly dated (U-Pb in zircon) at 650-620Ma, but localised plutons have been documented at 605Ma (Johnson, 2006). U-Pb analyses from the Kawr Suite are summarised in Chapter 3.2.2. This sample was dated because it forms what is thought to be a fractionated endmember in the Kawr Suite.
Zircons from this Kawr Suite sample are predominantly yellow-brown stubby euhedral prisms ~50-100µm in length. Overall, images display homogeneous dark-grey thickly zoned zircons with a tendency for darker rims (Figure 3.12 and Appendix 3). Multiple grains contain finely laminated growth with a bright CL response and illustrated no obvious discolouration between cores and rims. Several zircons exhibit grey overprinting from the rims that covers prior magmatic oscillatory zoning. This compositional zoning is very finely laminated, but since no core-rim analysis was preformed, it is unclear if similar ages would occur. The prismatic shapes are
65 pronounced towards the rims of the grains. Most stubby prisms correspond with S12- S15 zircon types with a temperature of ~7500C (Pupin, 1980). However, some grains exhibit traits of S19 (~8500C) structure.
Figure 3.12: A) A concordia plot illustrating the poorly concordant crystallisation age of 605Ma constrained from 11 individual grain analyses (Appendix 2, Table 12). The weighted average values (1 σ error) have been numerically rearranged in descending order to highlight the minimum and maximum values. Raw isotope age data was processed using Glitter software (Van Achterbergh et al., 2001) and conveyed using the Isoplot macro (Ludwig, 2000). B) An oscillatory zoned zircon image representing a typical zircon type analysed from the Kawr Suite (Appendix 3, Figure A3.12). The calculated initial ɛHf (at U-Pb age) from Hf isotope analysis is also provided and described in Chapter 3.3.
11 individual zircon grain analyses yielded a U-Pb concordia age of 605±18Ma (MSWD=4.9) and a 206Pb-238U weighted average age of 608±12Ma (MSWD=4.6). These zircons illustrate a poorly constrained crystallisation age, but surprisingly are reasonably concordant (Figure 3.12).This is interpreted not as the result of inherited ages, but as being consistent with elevated 204Pb in the analyses. The age range from
66 ~640-580Ma not only corresponds with the published age of the suite, but is homogeneous with the accurately dated sample kw42 in Chapter 3.2.1e.
Despite the elevated 204Pb values, the 11 analyses are interpreted to yield the crystallisation age of this suite. The mean concordancy is 88%, just outside >10% discordance. However, this is mainly attributed to 2 grains yielding a concordance of 65% and 69%. These display elevated 207Pb/206Pb ages of 956Ma and 877Ma respectively. The analysed zircons are still used in the mean calculation. This is because there are a limited number of analyses and both contain a 206Pb-238U age of 622Ma and 605Ma, which is within 1σ error from the mean age of the suite. 5 analyses have <10% discordance with the remaining 4 at ~80-90%. All raw data are presented in Appendix 2, Table 12. Overall, this suite produced an age of 608Ma consistent with post-tectonic magmatism (<636->600Ma). The significance of this age in relation to southern Asir and Afif microplate accretion is discussed further in Chapter 8.4.
3.2.1m Idah Suite (id): Alkali-Granite.
The undeformed Idah Suite perthitic alkali-granites (Appendix 1.4) cover vast areas of the Ha’il terrane and spread into the northern Afif terrane east of the Nabitah Suture (Figure 8.3). These intrude older post amalgamation basins such as the Hadn Formation (598Ma) and have been directly dated (U-Pb in zircon) at 620-615Ma (Johnson, 2006). U-Pb analyses from the Idah Suite are summarised in Chapter 3.2.2.
Zircons from the Idah Suite are predominantly brown stubby euhedral prisms ~50-100µm in length. However, there are also colourless elongate euhedral prisms ~100-250µm. Despite the morphological differences these zircons reveal similar ages. Overall, images display fine to very fine oscillatory zoning with generally bright CL responses (Figure 3.13 and Appendix 3). Stubby prisms convey a continuous alternating sequence of fine dark and bright zoning. Multiple grains exhibit bright cores with dimming towards the rim. However, most grains display darker cores with intermittent brighter zones terminating at darker rims. Stubby prisms contain no apparent overgrowths and with the exception of one grain (possibly an S19), most stubby prisms are S8-10 zircons forming at a temperature of ~7000C (Pupin, 1980).
67 Figure 3.13: A) A concordia plot illustrating the poorly concordant crystallisation age of 616.6Ma Ma constrained from 20 individual grain analyses (Appendix 2, Table 13). The weighted average values (1 σ error) have been numerically rearranged in descending order to highlight the minimum and maximum values. Raw isotope age data was processed using Glitter software (Van Achterbergh et al., 2001) and conveyed using the Isoplot macro (Ludwig, 2000). B) A finely oscillatory zoned zircon image representing a typical zircon type analysed from the Idah Suite (Appendix 3, Figure A3.13). The calculated initial ɛHf (at U-Pb age) from Hf isotope analysis is also provided and described in Chapter 3.3.
Numerous elongate prisms have similar characteristics of the stubby zircons, but differ in the oscillatory zoning. These needle like grains have no obvious cores, but sometimes contain a darker sliver in the middle. The very fine oscillatory zoning
68 conveys a homogeneous CL response. These zircons become increasingly prismatic towards the rims (Figure 3.13). This morphology suggests that a change in growth rate occurred (faster growing indistinguishable core to a slower growing prismatic rim). This may reflect a possible change in magma ascension rate. Overall, the elongate prisms reflect P2-P3 shaped zircons at a temperature of ~700-7500C (Pupin, 1980).
20 individual zircon grain analyses yielded a U-Pb concordia age of 616.6±8.7Ma (MSWD=1.03) and a 206Pb-238U weighted average age of 607.9±6.6Ma (MSWD=1.3). These zircons exhibited no Pb loss or inheritance, but have a somewhat poor concordance (Figure 3.13). Despite the fluctuation in concordancy, the 20 analyses are interpreted to yield the crystallisation age of the suite. The mean concordancy is 90%, but two grains as low as 59% and 62% are recorded. These display elevated 207Pb/206Pb ages of 1020Ma and 962Ma respectively. However, these analyses are still used in the mean calculation because both contain a 206Pb-238U age of 597Ma and are within 1σ error from the mean age of the suite. The elevated Pb observed in these grains posed difficulties in obtaining a concordant crystallisation age. Only 10 of 20 analyses recorded are <10% discordant. The remaining 8 grains range from 80-90% concordancy. All raw data are presented in Appendix 2, Table 13.
Fluctuations in 204Pb isotopes were recorded in primary oscillatory zoning. This created difficulties in obtaining concordant ages and caused age differences between zircon cores and rims. Fortunately, the 206Pb-238U ages were unaffected, but elevated 204Pb values were discarded because these cannot be accurately corrected. This Pb interference was primarily confined to outer zones in the stubby prismatic zircons and no obvious decolouration revealed this. As a result, only inner zones of stubby and elongate zircons were targeted. Overall, this suite produced an age of 608Ma consistent with post-tectonic magmatism (<636->600Ma). The tectonic significance of this age is discussed further in Chapter 8.4.
69 3.2.1n Al Khushaymiyah Suite (ky): Quartz-Monzonite.
This perthitic suite (Appendix 1.5) consisting of multiple locally named intrusions, is spread over the southern Afif terrane (SW of the Halaban Suture) near the eastern part of the Shield (Figure 8.3). The suite intrudes the older Murdama Group sediments (~630Ma) with the main body directly dated at 611-595Ma (Johnson, 2006). U-Pb analyses from the Al Khushaymiyah Suite are summarised in Chapter 3.2.2.
The Al Khushaymiyah Suite quartz-monzonite sample ky129 contains 3 zircon morphologies (Figure 3.14 and Appendix 3). Some zircons are colourless-yellow elongate euhedral prisms ~100-200µm in length. These exhibit no obvious core and rim zoning, but rather a homogeneous grey recrystallised nature. This is with the exception of one grain (Figure 3.14), which illustrates a darker core (faint zoning) surrounded by a grey homogeneous zone. Towards the zircon tips, evidence of fine zoning is apparent. Faint laminations can be seen in some grains with possible prismatic shapes towards the rims. Within these grains there is a tendency for a bright response on the outer rims. Zircon morphology is difficult to classify, but possibly exhibit S7-P2 type characteristics, which correspond with ~7000C (Pupin, 1980).
Other zircons are yellow-pink stubby euhedral prisms ~50-150µm in length. These show no obvious recrystallisation or overgrowths in grains. These convey fine compositional zoning with a tendency for bright rims (Figure 3.14). There appears to be a mixture of darker and bright cores. The former portrays microcracking, most likely due to high radioactivity. Numerous grains display equant, octagon style prismatic shapes, which appear to correlate with S24 types at a high temperature of ~8500C (Pupin, 1980). Some grains display slightly cooler (~7500C) S12-S14 characteristics.
Another zircon morphology is colourless-brown elongate prisms ~150-250µm in length. These are similar to the first zircons described, but display prominent oscillatory zoning (Figure 3.14). The primary magmatic zoning is almost continuous from core to rim. Cores vary from dark sliver like needles to small prismatic shapes. Some large grains even display homogeneous grey xenocrystic style cores surrounded by thick bright banding. However, multiple analyses revealed no significant difference between cores and rims, suggesting that the cores are products of recrystallisation. The
70 larger zircons have a tendency for darker rims in contrast to homogeneously bright needle like grains. Some elongate needles display partial overgrowths towards the rims and some dark sliver like cores appear to be reworked. Overall, this group correlates with P2-P3 zircon types with a temperature of ~700-7500C (Pupin, 1980).
Figure 3.14: A) A concordia plot illustrating the poorly concordant crystallisation age of 609.7Ma constrained from 24 analyses, 22 of which are individual grains (Appendix 2, Table 14). The weighted average values (1 σ error) have been numerically rearranged in descending order to highlight the minimum and maximum values. Raw isotope age data was processed using Glitter software (Van Achterbergh et al., 2001) and conveyed using the Isoplot macro (Ludwig, 2000). B) A representation of the 3 zircon morphologies found in sample ky129 (Appendix 3, Figure A3.14). The calculated initial ɛHf (at U-Pb age) from Hf isotope analysis is also provided and described in Chapter 3.3.
71 24 analyses from 22 individual zircon grains yielded a U-Pb concordia age of 609.7±8.5Ma (MSWD=1.7) and a 206Pb-238U weighted average age of 601.2.6±5.2Ma (MSWD=2). These zircons exhibited no Pb loss or inheritance, but produce a poor concordance (Figure 3.14). The mean concordancy is 82% with only 5 out of 24 analyses showing <10% discordance. The remaining 19 values have elevated 207Pb/206Pb ages and pose difficulties in obtaining a tight concordancy. The lowest values are in the 60% concordance range, but most are 80-90% concordant. However, all 24 analyses are used in the mean calculation because they have 206Pb-238U ages within 1σ error of the mean age. Overall, the suite age of 601Ma provides a minimum stitching age for the southern Ad Dawadimi and Afif terranes. The tectonic significance of this age is discussed further in Chapter 8.4.
3.2.1o Malik Granite (kg): Granite.
This undeformed garnet-bearing granite (Appendix 1.5) is confined to the northeastern margin in the Ad Dawadimi terrane (Figure 8.3). This suite has not been directly dated, but is assumed to be conformable with the Idah Suite to which it intrudes. It is therefore classified as 620-615Ma (Johnson, 2006). U-Pb analyses from the Malik Granite are summarised in Chapter 3.2.5.
Zircons from this Malik Granite are predominantly colourless euhedral prisms ~100-200µm in length. Overall, images display a homogeneous thick dark core and striking bright rims (Figure 3.15 and Appendix 3). The obvious characterisation of cores and rims, although visually distinguishable, bare no apparent changes in age. Most grains do not show primary zoning, but rather show thick bands of white/grey colour surrounding a dark interior. There are rare larger grains that display very fine grey banding at prism ends. One grain does not follow suit and appears to be a faint thickly zoned stubby prism ~50µm, but displays a compatible age with the rest of the grains. There is no standout overprinting of grains and the zircon morphology is indicative of G1-P1 shapes, corresponding with a lower temperature of ~600-6500C (Pupin, 1980). This cooler temperature and lack of complex zoning possibly reflects the crustal type nature of the suite
72 Figure 3.15: A) A concordia plot illustrating the relatively poor concordancy of the Malik Granite. The crystallisation age of 600.3Ma is constrained from 11 analyses, 9 of which are individual zircon grains (Appendix 2, Table 15). The significance of this age is discussed further in Chapter 7.7. The weighted average values (1 σ error) have been numerically rearranged in descending order to highlight the minimum and maximum values. Raw isotope age data was processed using Glitter software (Van Achterbergh et al., 2001) and conveyed using the Isoplot macro (Ludwig, 2000). B) A poorly zoned zircon image representing a typical zircon type analysed from the Malik Granite (Appendix 3, Figure A3.15). The calculated initial ɛHf (at U-Pb age) from Hf isotope analysis is also provided and described in Chapter 3.3.
11 analyses from 10 individual zircon grains yielded a U-Pb concordia age of 600.3±8.6Ma (MSWD=0.29) and a 206Pb-238U weighted average age of 599.6±5Ma (MSWD=0.30). These zircons illustrate a reasonably constrained crystallisation age, but don’t convey the tightest concordance (Figure 3.15). This appears to be consistent with
73 elevated 207Pb-206Pb ages in the analyses. Despite the elevated Pb values, the 11 analyses are interpreted to yield the crystallisation age of this suite. The mean concordancy is 88%, just outside >10% discordance. 2 grains yielding a concordance of 79% are recorded and display elevated 207Pb/206Pb ages of 769Ma. These analyses are still used in the mean calculation because there are a limited number of analyses and they both contain a 206Pb-238U age of ~599Ma, which is within 1σ error from the mean age of the suite. 4 analyses have <10% discordance with the remaining 5 between ~80- 90%. All raw data are presented in Appendix 2, Table 15. Overall, this produced an age of 599Ma consistent with anorogenic magmatism (<600Ma). This indirectly provides the minimum age of the Idah Suite into which it intrudes. The tectonic implications are discussed in Chapter 8.5.
3.2.1p Admar Suite (ad): Syenite.
Admar Suite undeformed syenites (Appendix 1.3) lie midway between the Yanbu and B’ir Umq Sutures (Figure 8.3) and intrude the older deformed volcanics of the Al Ays Group (745-700Ma). The age of this group is classified as unknown, but according to Johnson (2006) has 3 unreliable Rb-Sr ages of 640, 602 and 583Ma. U-Pb analyses from the Admar Suite are summarised in Chapter 3.2.2.
Zircons are predominantly colourless-pink elongate euhedral prisms ~100- 200µm in length, but brown stubby prisms ~50-100µm are also observed. Overall, images display fine to medium oscillatory zoning with generally faint CL responses (Figure 3.16 and Appendix 3). Rare grains exhibit what appear to be homogeneous xenocrystic cores surrounded by brighter rims. However, these grains show no evidence of discordance between zones and are consistent with the mean age. Numerous grains display dark subrounded cores surrounded by grey finer zoned areas, but show no evidence of recrystallisation. The euhedral cores vary between grains, but generally convey S5-S10 and P1-P2 prismatic morphology (Pupin, 1980). These often have overgrowth textures that are not zoned, but rather a homogeneous blurred grey zone, before reaching occasional dark crystallised rims. This is interpreted as initial crystallisation in a magma chamber followed by rapid ascension to the surface. This
74 morphology suggests a temperature range of ~650-7000C (Pupin, 1980), which is consistent with the anorogenic rift related syenitic nature of the suite.
Figure 3.16: A) A concordia plot illustrating the tightly constrained crystallisation age of 602.5 Ma from 33 analyses, 29 of which are individual grains (Appendix 2, Table 16). The significance of this age in relation to Shield construction is discussed further in Chapter 8.5. The weighted average values (1 σ error) have been numerically rearranged in descending order to highlight the minimum and maximum values. Raw isotope age data was processed using Glitter software (Van Achterbergh et al., 2001) and conveyed using the Isoplot macro (Ludwig, 2000). B) A finely oscillatory zoned zircon image representing a typical zircon type analysed from the Admar Suite (Appendix 3, Figure A3.16). The calculated initial ɛHf (at U-Pb age) from Hf isotope analysis is also provided and described in Chapter 3.3.
3 analyses from 30 individual zircon grains yielded a U-Pb concordia age of 602.5±5.3Ma (MSWD=0.5) and a 206Pb-238U weighted average age of 599.2±3.8Ma (MSWD=0.68). These zircons exhibited no Pb loss or inheritance and the tight
75 concordance is interpreted to be the crystallisation age of the suite (Figure 3.16). The mean concordancy is 96 %, but two grains at 74% and 124% were recorded. These display fluctuating 207Pb/206Pb ages of 487Ma and 788Ma respectively. However, these analyses are still used in the mean calculation because the 206Pb-238U age of ~599Ma is identical to the mean age of the suite. This fluctuation was also seen in 17 zircon grains, which are >10% discordant. All raw data are presented in Appendix 2, Table 16. Overall, this produced an age of 599Ma consistent with anorogenic magmatism (<600Ma). The significance of this is discussed further in Chapter 8.5.
3.2.1q Al Bad Granite Super Suite (abg): Alkali-Granite.
This undeformed suite (Appendix 1.1) consists of multiple individually named intrusions and covers the northern tip of Midyan terrane near the border of Jordan (Figure 8.3). This group has a poorly constrained age of 586Ma and 577Ma obtained from Rb-Sr isochron and U-Pb in zircon methods (Johnson, 2006). U-Pb analyses from the Al Bad Granite Super Suite are summarised in Chapter 3.2.2.
Zircons from the Al Bad alkali-granite are exclusively pink-brown stubby euhedral prisms that range from ~50-150µm in length. Overall, images display medium to very fine oscillatory zoning with generally bright CL responses (Figure 3.17 and Appendix 3). Most grains exhibit homogeneously bright fine laminations with a tendency for dimming towards the rims. There appears to be a mixture of zircons with very bright cores and those with darker ones. Surprisingly, there is no significant age difference, but slightly elevated 232Th is recorded. No significant overgrowths or recrystallisation in grains is evident. One grain however, has a complex core, but was not analysed. In general, there are two types of morphology observed: S8-S10 (~7000C) and S13-15 (~7500C) zircon types (Pupin, 1980). A few grains display the hotter structures in the cores, but are overgrown with the cooler types towards the rims.
Finely laminated oscillatory zoning was observed, but as illustrated in Figure 3.17, no significant age difference between cores and rims was recorded. As a consequence, it was unnecessary to target both cores and rims of every zircon grain.
76 Only the inner zones were targeted for analysis because they are assumed to represent the crystallisation age of the suite.
Figure 3.17: A) A concordia plot illustrating the tightly constrained crystallisation age of 602.9Ma from 31 analyses, 29 of which are individual grains (Appendix 2, Table 17). This age provides the minimum stitching age between the Midyan and Hijaz plates and is discussed further in Chapter 8.5. The weighted average values (1 σ error) have been numerically rearranged in descending order to highlight the minimum and maximum values. Raw isotope age data was processed using Glitter software (Van Achterbergh et al., 2001) and conveyed using the Isoplot macro (Ludwig, 2000). B) A finely oscillatory zoned zircon image representing a typical zircon type analysed from the Al Bad Suite (Appendix 3, Figure A3.17). The calculated initial ɛHf (at U-Pb age) from Hf isotope analysis is also provided and described in Chapter 3.3.
31 analyses from 29 individual zircon grains yielded a U-Pb concordia age of 602.9±5.6Ma (MSWD=0.75) and a 206Pb-238U weighted average age of 597.4±4.8Ma
77 (MSWD=1.2). These zircons exhibited no Pb loss or inheritance and the tight concordance is interpreted to be the crystallisation age of the suite (Figure 3.17). The mean concordancy is 93 % with 10 of 31 displaying a >10% discordance. This is predominantly from 2 zircon grains at 77% and 77% concordance that record elevated 207Pb/206Pb ages of 761Ma and 791Ma respectively. However, these analyses are still used in the mean calculation because the 206Pb-238U age is within 1σ error of the mean age of the suite. The remaining 8 grains lie between ~80-90% concordance and also exhibit this elevated Pb trend. All raw data are presented in Appendix 2, Table 17. Overall, this suite produced an age of 597Ma consistent with anorogenic magmatism (<600Ma) and provides the minimum stitching age between the Midyan and Hijaz plates (Chapter 8.5).
3.2.1r Al Hawiyah Suite (hwg): Granite.
This undeformed perthitic suite (Appendix 1.8) locally consists of multiple units covering a significant area of the western Asir terrane, southeast of Jeddah (Figure 8.3). It has a poorly constrained age of 630-590Ma (Johnson, 2006). Rb-Sr methods bear local ages of 515Ma and even as low as 117Ma, but are thought to be anomalous dates. U-Pb analyses from the Al Hawiyah Suite are summarised in Chapter 3.2.2.
The Al Hawiyah Suite granite contains 3 different zircon morphologies in sample hwg07 (Figure 3.18 and Appendix 3). Some zircons are colourless elongate euhedral prisms ~150-200µm in length. These exhibit no obvious core and rim zoning, but rather a homogeneous grey or dark xenocrystic type nature. The faint CL response however, does show a tendency for dimming towards the rims. There are no obvious overgrowths or recrystallisation displayed in any grains. Zircon morphology is difficult to classify, but grains generally exhibit P1-P2 type characteristics, which correspond with ~650-7000C (Pupin, 1980).
Another zircon type is brown-pink elongate euhedral prisms ~200-350µm in length. Unlike any other groups in this suite, these zircons display striking medium-fine compositional oscillatory zoning (Figure 3.18 and Appendix 3). Although the zoning varies in thickness, most grains exhibit a continuous sequence of bright and dark
78 Figure 3.18: A) A concordia plot illustrating the poorly concordant crystallisation age of 594.9Ma constrained from 27 analyses, 23 of which are individual grains (Appendix 2, Table 18). The weighted average values (1 σ error) have been numerically rearranged in descending order to highlight the minimum and maximum values. Raw isotope age data was processed using Glitter software (Van Achterbergh et al., 2001) and conveyed using the Isoplot macro (Ludwig, 2000). B) A representation of the 3 zircon morphologies found in sample hwg07 (Appendix 3, Figure A3.18). The calculated initial ɛHf (at U-Pb age) from Hf isotope analysis is also provided and described in Chapter 3.3.
79 laminations from core to rim. All grains have a tendency for darker cores with intermittent bright zones and finally dimmed rims. One grain conveys a bright outer zone that constitutes almost 80% of the structure. Despite the distinct zoning in all grains, there is no apparent age difference (Figure 3.18). Some larger zircons contain inclusions (presumably apatite minerals) residing in the inner zone of grains. These illustrate a wide variety of morphologies with numerous grains containing up to three prismatic overgrowths. Typically, the grains are S18-S19-P4 (~8000C) zircons in the inner zones, but are overgrown by cooler (~7500C) S12-S13-P2-P3 types (Pupin, 1980). This may reflect a rapidly ascending magma chamber.
The last zircon variety is colourless elongate prisms ~150-350µm in length. These are similar to the first zircons described, but display simple, yet distinct zoning (Figure 3.18 and Appendix 3). Overall, images exhibit distinct bright bands, but are not always limited to the rims. Several grains show extremely bright inner zones surrounded by dark prismatic rims. This zoning is very thick, almost non-existent and displays no evidence of recrystallisation or overgrowths. The large grains appear to illustrate a homogeneous grey xenocrystic core with a dark prismatic rim. However, analysis of both zones reveals no significant age difference. Overall, these correlate with S10-P2 zircon types with a temperature of ~7000C (Pupin, 1980).
27 analyses from 23 individual zircon grains yielded a U-Pb concordia age of 594.9±8.7Ma (MSWD=2.1) and a 206Pb-238U weighted average age of 591.9±5.2Ma (MSWD=2.1). These zircons exhibited no Pb loss or inheritance, but produced a poor concordance (Figure 3.18). The mean concordancy is 86% with only 10 out of 27 analyses showing <10% discordance. The remaining 17 values have fluctuating 207Pb/206Pb ages and pose great difficulties in obtaining a tight concordancy. The lowest value recorded is 68%, 5 are 70-80% and the remainder between 80-90%. However, all 27 analyses are used in the mean calculation because they have 206Pb-238U ages within 1σ error of the mean age. Overall, this suite produced an age of 591Ma consistent with anorogenic magmatism (<600Ma). The spatial emplacement of this suite is clearly within plate. This tectonic significance is discussed further in Chapter 8.5.
80 3.2.1s Mardabah Complex (mr): Syenite.
The undeformed Mardabah Complex is an isolated primitive syenite (Appendix 1.3) confined to the central Hijaz terrane, approximately 50km east of the Yanbu Suture north of Yanbu al Bahr (Figure 8.3). This unit has not been directly dated, however, structural relationships define this unit as Ediacaran in age and possibly one of the youngest suites in the Shield (Johnson, 2006). U-Pb analyses from the Mardabah Complex are summarised in Chapter 3.2.2.
Mardabah Complex zircons are predominantly pink euhedral prisms that range from ~200-600µm in size. These are the largest zircons of any suite sampled in the Arabian Shield. Overall, images display homogeneous grey xenocrystic cores and grey fine to medium oscillatory zoned rims (Figure 3.19 and Appendix 3). Grains frequently convey multiple overgrowths towards the rims, but do not exhibit compositional changes in CL response. This is with the exception of one zircon containing a darker core and thicker brighter grey rims. A few grains appear to lack fine lamination and convey a recrystallised appearance. Patchy overgrowths are interpreted to be the continuous cycle of new crystallisation in the magma chamber. Many zircons exhibit distinctive morphological shapes, particularly towards the rims of the grains. In general, these display pyramidal tendencies corresponding with S11-S12 (~7500C) zircons, but some grains convey S21-S22 (~8500C) type morphologies (Pupin, 1980).
17 analyses from 14 individual zircon grains yielded a U-Pb concordia age of 525.7±4.3Ma (MSWD=1.2) and a 206Pb-238U weighted average age of 525.6±3.8Ma (MSWD=1.15). These zircons exhibited no Pb loss or inheritance and convey a reasonably tight concordance, interpreted to be the crystallisation age of the suite (Figure 3.19). The mean concordancy is 105%, but two grains at 72% and 125% were recorded. These display fluctuating 207Pb/206Pb ages of 418Ma and 730Ma respectively. However, these analyses are still used in the mean calculation because the 206Pb-238U age of 523-526Ma is identical to the mean age of the suite. This fluctuation was also seen in 6 zircon grains, which are >10% discordant. Overall, this suite produced a crystallisation age of 525Ma, consistent with anorogenic magmatism (<600Ma). The tectonic implications of this age are discussed in Chapter 8.5.
81 Figure 3.19: A) A concordia plot illustrating the crystallisation age of 525.7Ma constrained from 17 analyses, 14 of which are individual grains (Appendix 2, Table 19). This age is significant as it post dates the regional unconformity at ~542Ma (see Figure 3.21 and Chapter 8.6 for discussion). The weighted average values (1 σ error) have been numerically rearranged in descending order to highlight the minimum and maximum values. Raw isotope age data was processed using Glitter software (Van Achterbergh et al., 2001) and conveyed using the Isoplot macro (Ludwig, 2000). B) A finely oscillatory zoned zircon image representing an abnormally large (~500µm), nevertheless, typical zircon type analysed from the Mardabah Complex (Appendix 3, Figure A3.19). The calculated initial ɛHf (at U-Pb age) from Hf isotope analysis is also provided and described in Chapter 3.3.
82 3.2.2 Arabian Shield U-Pb Geochronology Summary and Discussion.
The U-Pb concordia and probability diagrams convincingly show 4 distinguished age groups within the Shield (Figures 3.20 and 3.21). These are summarised as the following: 1) Makkah Suite (~867Ma) in the western Shield; 2) Shufayyah and Jar-Salajah Complexes and Subh Suite (~730-636Ma) in the western Shield; 3) Kawr, Al Hafoor, Wadbah, Ibn Hashbal, Ar Ruwaydah Haml, Idah, Al Khushaymiyah, Admar, Al Bad and Al Hawiyah Suites and the Najirah and Malik Granites (~636-600Ma) confined to the eastern and western Shield; and 4) Mardabah Complex (~525Ma) in the western and eastern Shield. Conveniently, most analyses are confined to the post-tectonic realm. This significant event is thought to highlight the final amalgamation phases of continental accretion and provides a convenient focal point for further investigation (Chapter 8).
Figure 3.20: A U-Pb concordia diagram summarising the 452 zircon analyses obtained from 19 granitic samples from the Arabian Shield. These values were processed and conveyed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000). It is clear that there are 4 distinct phases of magmatism that have occurred in the Shield. The significance of these ages is discussed further in Chapter 8.
83 A closer inspection of the post-tectonic intrusives actually reveals two distinct groups: Group 1) post-tectonic perthitic suites (636-600Ma) such as the Najirah Granite and Al Hafoor, Al Khushaymiyah, Ar Ruwaydah, Haml, Ibn Hashbal, Idah, Kawr and Wadbah Suites. These are commonly juxtaposed or intrude accretionary suture zones such as the Nabitah Orogenic Belt (terminates at ~640Ma) and Halaban Suture (terminates at ~630Ma). These are thought to be immediately pursuant to tectonic orogenesis and are possibly still connected to slab related processes, hence provide the minimum age of terrane accretion; and Group 2) the occurrence of anorogenic (<600Ma) within plate intrusives such as the Abanat, Admar, Al Bad Granite and Al Hawiyah Suites and the Mardabah Complex. These all exhibit ages <600Ma and are isolated from plate boundaries. It is suggested these suites formed well after (~30- 40Ma) orogenesis and are discontinuous with subduction processes. Indirectly, these suites mark the lower limit of post-tectonic age magmatism and signify the change in tectonic processes (Chapter 7.6).
Interestingly, island arc (Makkah Suite), syncollisional (Shufayyah and Jar- Salajah Complexes) and post-orogenic (Najirah Granite and Kawr and Wadbah Suites) age intrusions that are directly involved in accretion or immediately pursuant to orogenesis share distinguished zircon morphologies within a sample. This poses the possibility of discrete age groups within a sample, hence different tectonic mechanism to that of the tightly constrained anorogenic suites isolated from plate boundaries. Geochemical and additional geochronological examination of these zircon morphological groups is explored further in Chapter 5 and 6 respectively.
Overall, this U-Pb data convincingly tightens and adds to the current geochronological data bases from the Arabian Shield (Chapter 3.2). Many samples that previously had poorly constrained or even unidentified dates now contain concordant, tightly defined crystallisation ages. The identification of granitic ages in conjunction with pre-existing data (Johnson, 2006; Johnson et al., 2011) allows the tectonic reconstruction of the Arabian Shield (Chapter 8). Most importantly, the analysis of anorogenic granitoids allows a minimum stitching age between microplate terranes to be outlined and in a broader sense, their significance in reconstructing Gondwana (Chapter 8.6).
84 Figure 3.21: A probability diagram summarising the 206Pb-238U data of 452 zircon analyses (Chapter 3.2). These values were processed and conveyed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000). Note the 4 distinct phases of magmatism placed in a geological time frame constructed from geochronological data obtained from Doebrich et al. (2007), Hargrove (2007) and Johnson et al. (2011). A regional unconformity at ~542Ma marks the cessation of magmatism in the Shield. However, anorogenic rift related magmatism is still occurring, thus suggesting a new unconformity at ~500Ma (Chapter 8.6). The separation of post-tectonic and anorogenic magmatism is interpreted to mark the transition between slab related and lithospheric delamination processes (Chapter 7).
85 Table 3.1 part1: A summary of LA-ICPMS U-Pb zircon geochronology obtained from of all 18 sampled granitic suites across the Arabian Shield. Data was processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000). The mean weighted average age values are quoted with 2σ error bounds. All data values including concordia isotope ratios are displayed in Appendix 2.
No. Zircons Magmatic Published Geochronology Sample Terrane 207Pb/206Pb 206Pb/238U 207Pb/235U 208Pb/232Th Concordancy Analysed Timing (Johnson, 2006) 817-678Ma (poorly constrained) Makkah Suite (dm01a) Jiddah 38 855±15 845.6±4.9 847.8±5.9 779±12 99 Island Arc method not stated. 859Ma from Kennedy et al. (2011)
U-Pb in zirocn=715Ma Shufayyah Complex (su216) Hijaz 47 719±14 715.4±3.6 716.7±4 659±25 101 Synorogenic (undocumented)
U-Pb in zirocn=745-695Ma Jar-Salajah Complex (js202) Hijaz 29 720±12 693.2±6.3 700.5±4.7 719±12 96 Synorogenic (unreliable)
Wholerock Rb-Sr Subh Suite (sf209) Hijaz 22 713±14 698.7±5.5 701.5±6.4 605±55 98 Synorogenic isochron=659Ma
U-Pb in zirocn=650-605Ma Kawr Suite (kw42) Asir 26 664±21 611.7±6.5 622.2±5.6 594±23 95 Post-tectonic (poorly constrained)
Age Unknown. Structural Al Hafoor Suite (ao85) Asir 16 730±31 636±4 656.6±6.7 754±22 88 Post-tectonic relationships=Ediacaran
U-Pb in zirocn=641Ma Najirah Granite (nr120) Asir 20 660±29 607±7.9 619.6±8 590±33 89 Post-tectonic SHRIMP=576Ma
Wadbah Suite (wb65) Asir 26 633±17 615.9±4.9 620.5±5.8 672±11 98 Post-tectonic SHRIMP=606Ma
U-Pb in zircon=640-617Ma Ibn Hashbal Suite (ih68) Asir 19 695±44 617.6±5.2 633.9±9.6 671±65 91 Post-tectonic (poorly constrained)
2 units:605-565Ma and 587- Ar Ruwaydah Suite (ku139) Ad Dawadimi 20 622±31 612.1±4.9 613.9±9.2 482±42 98 Post-tectonic 575Ma (SHRIMP and Rb-Sr isochron)
86 Table 3.1 part2: A summary of LA-ICPMS U-Pb zircon geochronology obtained from of all 18 sampled granitic suites across the Arabian Shield. Data was processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000). The mean weighted average age values are quoted with 2σ error bounds. All data values including concordia isotope ratios are displayed in Appendix 2.
No. Zircons Magmatic Published Geochronology Sample Terrane 207Pb/206Pb 206Pb/238U 207Pb/235U 208Pb/232Th Concordancy Analysed Timing (Johnson, 2006)
Haml Suite (hla110) Afif 15 673±35 608.6±8.1 623.2±7.2 588±17 88 Post-tectonic U-Pb in zircon=640-625Ma Some plutons <610Ma
U-Pb in zircon=650-605Ma Kawr Suite (kw51p) Asir 11 708±77 608±12 628±20 613±30 88 Post-tectonic (poorly constrained)
Idah Suite (id159) Ha'il 20 680±28 607.9±6.6 622.1±7 638±37 90 Post-tectonic U-Pb in zircon=620-615Ma
Al Khushaymiyah Suite (ky129) Ad Dawadimi 24 753±37 601.2±5.2 631.9±7.5 598±20 82 Post-tectonic U-Pb in zircon=611-595Ma
Age Unkown. Structural Malik Granite (kg150) Ad Dawadimi 11 683±43 599.6±5 616.6±8.4 610±15 88 Anorogenic Relationships=620-615Ma
3 Rb-Sr ages: 640, 602 and Admar Suite (ad194) Hijaz 33 633±30 599.2±3.8 605.3±6.5 601±14 96 Anorogenic 583Ma
U-Pb in zircon=577Ma Al Bad Granite Suite (abg179) Midyan 31 630±26 597.4±4.8 605.2±5.8 603±30 93 Anorogenic Rb-Sr isochron=586Ma
Rb-Sr & SHRIMP=630-590Ma Al Hawiyah Suite (hwg07) Asir 27 704±31 591.9±5.2 615.3±7.1 554±39 86 Anorogenic (poorly constrained)
Age Unknown. Structural Mardabah Complex (mr191) Hijaz 17 507±28 525.6±4.7 523.3±7.1 504±27 105 Anorogenic relationships=<600Ma
GJ Standard 268 608.8±4.5 600.9±1 602.4±1.1 614.6±5.8 99 GJ GEMOC - - 607.7±4.3 600.7±1.1 602±1 - - - - Plesovice Standard 92 341.2±7.5 342.6±1.5 342.4±1.5 347.6±6.3 101 Plesovice (Slama et al.2008) - 339.2±0.25 337.1±0.37 337.3±0.11 - -
87 3.3 Hafnium (Hf) Isotopes.
Following U-Pb geochronology, selected zircons from the same 19 granitic samples were analysed for Hf isotopic compositions. A detailed analytical method, including isotope calculations, is described in Appendix a2. Zircons with a <10% discordance were preferred, but were not always possible from suites such as the Al Hafoor, Al Hawiyah, Al Khushaymiyah, Haml and Kawr (kw51p) and the Malik Granite. The concordancy of these suites ranged from ~80-90% and is deemed reliable because of low REE compositions and their clustering with neighbouring concordant granitoids. The availability of exposed concordant zircon grains following U-Pb geochronology provided some limitations on Hf analysis. As displayed in Appendix 3, most laser ablation was conducted on adjacent U-Pb analysis wherever possible. The ablation pit was placed as close as possible without causing interference. Flaws in zircon morphology such as inclusions are considered trouble spots and were avoided.
Despite these limitations most samples contain 10-20 Lu-Hf analyses (Table 3.2). These adequately represent primary magmatic zircon trends. Multiple zircon morphologies within syncollisional and post-orogenic suites are also analysed and illustrate a homogeneous Hf isotopic composition i.e. no inheritance. Selected grains that exhibited obvious core and rim compositional zoning were targeted for multiple analyses. A combination of syncollisional (Jar-Salajah), post-tectonic (Ibn Hashbal) and anorogenic (Al Hawiyah) suites all contain multiple core rim analyses, but showed no significant change in calculated (at U-Pb age) initial ɛHf values.
Mean values from all 19 granitic suites are displayed in Table 3.2 and raw data in Appendix 4. These are used to construct Figures 3.22 and 3.23 which illustrate that all samples regardless of age are juvenile and contain ɛHf (t) values that range from ~
+5 to +10. The majority of the TDM and TDMcrust model ages are ~1Ga and 1.1Ga respectively, which possibly correlates with the break up of Rodinia (Chapter 8.7). Figure 3.22 displays 4 distinct clusters of Hf values corresponding with the western and eastern parts of the Shield. The western side contains more age diversity, but illustrates the most mantle homogeneity. Conversely, the eastern Shield is more tightly age constrained, but displays the most isotopic variation.
88 Figure 3.22: ɛHf vs. 206Pb-238U age diagram illustrating the evolution of sampled units across the Arabian Shield. Hf data was processed using HfTrax software (Payne, 2010) and model ages calculated using the 176Lu decay constant of 1.87x10-11 (Scherer et al., 2001) and average 176Lu/177Hf crustal composition of 0.015 (Griffin et al., 2002). Mean crustal model ages of each suite are displayed, highlighting the minimum and maximum values (dashed lines). These indicate juvenile melts associated with crustal sources possibly related to Pan-African rifting (Chapter 8.7). All suites exhibit juvenile characteristics from a homogeneous mantle, but appear to show subtle isotopic variation within the eastern Shield granitoids (inset). This is interpreted to be a transition from suture related to within plate magmatism resulting in a decrease of crustal components with time. This is discussed in Chapter 7. The square inserts A, B, C and D are displayed in Figure 3.23.
89 3.3.1 Western Shield.
Island arc magmatism (Makkah Suite 867-829Ma) consist of a tight ɛHf cluster ranging from +8 to +11 (Figure 3.23). Syncollisional magmatism (~730-636Ma) is composed of the Shufayyah and Jar-Salajah Complexes and the Subh Suite from the Hijaz terrane. The Shufayyah Complex has an ɛHf composition from +9 to +11, the Jar- Salajah Complex ranges from +4 (2 analyses) to +8 - +12 (13 analyses) and the Subh Suite ranges from -2 (one analysis) to +6 - +10 (8 analyses). The slight isotopic variation is attributed to slightly older crustal sources as discussed Chapter 8.7. The remainder of the western Shield is composed of anorogenic (<600Ma) within plate granitoids. The Admar Suite and Mardabah Complex (youngest syenite at 525Ma) residing in the Hijaz terrane both contain a ɛHf isotopic spread of +5 to +10. The Midyan terrane hosts the Al Bad Granite Super Suite which produced a similar range from +6 to +10. The Asir terrane containing the Al Hawiyah Suite also portrays a similar range from +6 to +9.
3.3.2 Eastern Shield.
This eastern Shield has been split into two components: 1) post-tectonic (<636- >600Ma) Al Ruwaydah, Haml and Idah Suites together with the S-type Malik granite that define the tightly grouped yellow field in Figure 3.23. The ɛHf values are juvenile, but individually range from +7 to +10, +8 to +10, +7 to +11 and +7 to +10 respectively; and 2) Post-tectonic–anorogenic (<636Ma) intrusions associated with suture zones including the Al Hafoor and Al Khushaymiyah Suites and the Najirah Granite. The first two suites form tight clusters of ɛHf +5 to +8 and +3 and +6 respectively. The Najirah Granite displays a much broader range of +4 to +10. These illustrate the initial stages of magmatic transition, which will be discussed further shortly.
90 Figure 3.23 part1: ɛHf vs. 206Pb-238U age diagrams (Figure 3.22 sections A and B) illustrating the evolution of discrete magmatic events in the Arabian Shield. The Hf data was processed using HfTrax software (Payne, 2010) and model ages calculated using the 176Lu decay constant of 1.87x10-11 (Scherer et al., 2001) and an average 176Lu/177Hf crustal composition of 0.015 (Griffin et al., 2002). A) Juvenile island arc melts of the Jiddah Terrane. The maximum and minimum crustal model ages of the Makkah Suite are displayed. B) Syncollisional juvenile melts alongside the Makkah Suite crustal array (dashed blue). Note the large isotopic variation in some granitic units, possibly indicating a Rodinian crust source (Chapter 8.7).
91 Figure 3.23 part2: ɛHf vs. 206Pb-238U age diagrams (Figure 3.22 sections C and D) illustrating the evolution of discrete magmatic events in the Arabian Shield. The Hf data was processed using HfTrax software (Payne, 2010) and model ages calculated using the 176Lu decay constant of 1.87x10-11 (Scherer et al., 2001) and an average 176Lu/177Hf crustal composition of 0.015 (Griffin et al., 2002). C) Post tectonic suites show two crustal array groups, possibly coinciding with changing tectonic settings at 618Ma i.e. WPG extension (upper array) and continental- continental plates (lower array). D) Anorogenic within plate granitoid suites of the western Shield showing a somewhat homogeneous data spread. The tectonic implications are discussed in Chapter 8.7.
92 3.3.3 Nabitah Orogenic Belt.
The Nabitah belt forms the geological spine that stiches the western and eastern parts of the Shield together. Isotopically, this forms a convenient focal point as it visually contains two types of ɛHf groups. The Kawr, Ibn Hashbal and the Wadbah Suites are all post-tectonic-anorogenic (<636Ma) granitoids. Sample kw42 marks the older (636-597Ma) unit and has the lowest ɛHf values of the Nabitah intrusions. Theses range from ɛHf +4 to +8. The younger (608Ma) kw51p sample has the highest ɛHf range from +6 to +15. The Wadbah Suite contains a spread from ɛHf +4 to +10 while the Ibn Hashbal Suite contains a very tight ɛHf cluster from +8 to +10 (Figure 3.23).
Nabitah intrusions (Kawr, Ibn Hashbal and Wadbah Suites) play a vital role in the transition from subduction related to within plate related magmatism as illustrated in Figure 3.23. The older Kawr Suite sample kw42 in conjunction with eastern Shield suture related granitoids (Al Khushaymiyah and Al Hafoor Suites), define the lowest values ɛHf from +3 to +6. The slightly younger Najirah Granite and Wadbah Suite spread from ɛHf +4 to +10 with a distinction at ~618Ma to within plate granitoid values of ɛHf +7 to +10. This transition may be due to a change in mantle chemistry (becoming more juvenile with age) beneath the Nabitah Orogenic Belt. The tectonic significance of this is discussed further in Chapters 7 and 8.7.
Overall, this section illustrates that the granitic units, although discriminated well in age, are only subtly distinguished by Hf compositions. Isotopes highlight the juvenile nature of all magmatism in the Arabian Shield and the homogeneous mantle source in which they are derived. However, the subtle changes in isotopic composition between western and eastern magmatism may reflect a transition from subduction style to lithospheric processes which is discussed further in Chapter 7. Arabian Shield suites are compared to southern Indian suites to gauge global isotopic juvenility (Figure 3.24). Southern India is used as a comparison because of its similar age suites, association with Gondwana (Mozambique Ocean) and its differing crustal source ages (Archaean age). Figure 3.24 illustrates that southern Indian suites do not contain model source ages of Pan-African age nor are they juvenile suites, thus reinforcing the juvenile nature of the Shield and its possible link to Pan-African sources (Chapter 8).
93 Figure 3.24: ɛHf vs. 206Pb-238U age diagram illustrating just how juvenile the Arabian Shield suites (orange, red, green, blue) are when compared to similar age southern Indian suites also associated with the closure of the Mozambique Ocean. Mean crustal model ages of each suite are displayed, highlighting the minimum and maximum values (dashed lines) and are suggestive of Pan-African (Arabian Shield) and Archaean (Southern India) age sources. The significance of the source ages is discussed further in Chapter 8. Hf data was processed using HfTrax software (Payne, 2010) and model ages calculated using the 176Lu decay constant of 1.87x10-11 (Scherer et al., 2001) and average crustal composition of 0.015 (Griffin et al., 2002). Southern India data was taken from Teale et al. (2011).
94 3.3.4 Hafnium Isotope Summary.
Table 3.2 part1: A summary of LA-MC-ICPMS zircon Hf isotopic analysis obtained from 18 dated Arabian Shield granitic suites. Data was processed using HfTrax software (Payne, 2010) and displayed as mean values. The Hf model ages are calculated based on the 176Lu decay constant 1.87x10-11 after Scherer et al. (2001) and an average 176Lu/177Hf crustal composition of 0.015 (Griffin et al., 2002). All isotopic data values are displayed in Appendix 4.
206 238 176 177 176 177 No. Zircon Pb/ U TDM (Crustal) Hf/ Hf Hf/ Hf Sample 176Hf/177Hf 176Lu/177Hf 176Yb177Hf 178Hf/177Hf 176Hf/177Hf (t) ɛHf (t) spots Age (Ma) Age (Ga) CHUR (t) DM (t) Makkah Suite (dm)-sample dm01a- 19 842.6 0.282556 0.002036 0.080807 1.467252 0.282523 9.99 1.1 0.282242 0.282638 Jiddah Terrane
Shufayyah Complex (su)-sample 15 715.7 0.282632 0.001187 0.049987 1.467317 0.282616 10.26 0.98 0.282326 0.282735 su215-Hijaz Terrane
Jar-Salajah Complex (js)-sample 19 696.8 0.282634 0.002907 0.135679 1.467287 0.282596 9.4 1.02 0.282338 0.282749 js202-Hijaz Terrane
Subh Suite (sf)-sample sf209- 9 699.4 0.282598 0.003061 0.119417 1.467353 0.282558 7.86 1.12 0.282336 0.282747 HijazTerrane
Kawr Suite (kw)-sample kw42-Asir 11 617.1 0.282599 0.002112 0.089964 1.467342 0.282574 6.6 1.14 0.282388 0.282638 Terrane
Al Hafoor Suite (ao)-sample ao85- 13 634.7 0.282608 0.001893 0.08463 1.467257 0.282585 7.38 1.1 0.282377 0.282794 Tathlith Terrane
Najirah Granite (nr)-sample nr120- 17 605.8 0.282633 0.002036 0.107078 1.467247 0.282610 7.62 1.06 0.282395 0.282815 Ad Dawadimi Terrane
Wadbah Granite (wb)-sample 16 617.6 0.282639 0.000885 0.038315 1.4672281 0.282629 8.54 1.02 0.282387 0.282806 wb65-Asir Terrane
Ibn Hashbal Suite (ih)-sample ih68- 16 618.5 0.282661 0.001473 0.074615 1.467271 0.282644 9.1 0.98 0.282387 0.282805 Asir Terrane
Ar Ruwaydah Suite (ku)-sample 13 613.6 0.282641 0.001167 0.053102 1.467249 0.282628 8.41 1.02 0.28239 0.282809 ku139-Ad Dawadimi Terrane
Haml Suite (hla)-sample hla110- 15 608 0.282655 0.001026 0.044365 1.467266 0.282643 8.9 1 0.282393 0.282813 Afif Terrane
95 Table 3.2 part2: A summary of LA-MC-ICPMS zircon Hf isotopic analysis obtained from 18 dated Arabian Shield granitic suites. Data was processed using HfTrax software (Payne, 2010) and displayed as mean values. The Hf model ages are calculated based on the 176Lu decay constant 1.87x10-11 after Scherer et al. (2001) and an average 176Lu/177Hf crustal composition of 0.015 (Griffin et al., 2002). All isotopic data values are displayed in Appendix 4.
206 238 176 177 176 177 No. Zircon Pb/ U 176 177 176 177 176 177 178 177 176 177 Hf/ Hf Hf/ Hf Sample Hf/ Hf Lu/ Hf Yb Hf Hf/ Hf Hf/ Hf (t) ɛHf (t) TDM (Crustal) spots Age (Ma) CHUR (t) DM (t) Kawr Suite (kw)-sample 11 609.8 0.282695 0.001802 0.083608 1.467247 0.282675 10 0.92 0.282392 0.282812 kw51p-Asir Terrane
Idah Suite (dm)-sample 14 613 0.282654 0.001856 0.093554 1.46724 0.282633 8.59 1.01 0.28239 0.282809 id159-Ha'il Terrane
Al Khushaymiyah Suite (ky)- sample ky129-Ad Dawadimi 17 603.9 0.282562 0.001334 0.058208 1.467271 0.282547 5.34 0.99 0.282396 0.282816 Terrane
Malik Granite (kg)-sample 6 602.1 0.282674 0.003228 0.159475 1.467228 0.282631 8.5 1.01 0.282397 0.282817 kg150-Ad DawadimiTerrane
Admar Suite (ad)-sample 15 598.3 0.282634 0.000579 0.026077 1.467272 0.282628 8.08 1.03 0.282399 0.28282 ad194-Hijaz Terrane
Al Bad Granite Super Suite (abg)-sample abg179- 15 599.8 0.282656 0.002065 0.097518 1.467265 0.282523 8.3 1.02 0.282399 0.282819 Midyan Terrane
Al Hawiyah Suite (hwg)- 14 594.1 0.282636 0.00168 0.077359 1.467232 0.282523 7.62 1.06 0.282402 0.282823 sample hwg07-Asir Terrane
Mardabah Complex (mr)- 15 525 0.282667 0.000975 0.051687 1.467269 0.282523 7.5 1.01 0.282445 0.282873 sample mr191-HijazTerrane
Mud Tank 19 - 0.282501±22 0.000018±<1 0.001014±20 1.467272±91 - - - - - Mud Tank (Woodhead & - - 0.282507±6 ------Hergt, 2005)
Plesovice 38 - 0.282474±22 0.000101±4 0.006032±12 1.465632±13 - - - - - Plesovice (Slama et al., -- 0.282482±13 ------2008)
96 Chapter 4: Geochemical Constraints on Arabian Shield Plutonic Rocks.
4.1 Introduction.
The distinguished island arc (867-829Ma), syncollisional (<730-636Ma), post tectonic (<636-600Ma) and anorogenic (<600Ma) magmatic phases described in Chapter 3.2 undoubtedly represent different tectonic processes in Shield evolution. Unsurprisingly, these cycles produced a diverse range in plutonic mineralogy, which is subdivided into metaluminous, peraluminous, and peralkaline suites (Chapter 2).
However, many post-tectonic and anorogenic granitoids that contain classic A- type mineralogy in the Shield are derived in different tectonic settings: 1) intrude suture zones immediately following collision and exhibit fractionation from mafic cumulates; and 2) within plate suites isolated from plate boundaries absent of mafic cumulates (Chapters 2 and 3). Mapping and petrographic relationships already place doubt on the strictly rift-related, derivation of basaltic fractionation category as first described in the early years of classification (Chapter 1.2). Different tectonic settings (rift/convergent) produce the same granitic endmembers (Chapter 2) and grouping of all endmembers into one A-type category overlooks their geochemical diversity and the petrogenetic processes in which they formed.
This section aims to identify geochemical parameters that clearly discriminate classic A-type granitoids and use these to establish further their petrogenetic significance in Shield evolution (Chapters 7 and 8). The complex interplay of Arabian Shield oceanic and crustal fragments produce a diverse range of classic A-type granitoids reinforcing the need for re-examination of the geochemical parameters defined by early classification schemes.
97 4.2 Whole Rock Major and Trace Element Geochemistry.
Whole rock geochemistry results are summarised in Chapter 4.2.4 and displayed in entirety in Appendix 5. Geochemical methods are in Appendix a3-a6.
The following figures utilise published data from the Arabian-Nubian Shield to compare and contrast data obtained in this study. The published data are divided into 4 distinct MORB, I-type, fractionated A-type and within plate granitic fields based on geochronological and geochemical constraints (predominantly tectonic classification, major and trace element and Nd-Sm isotope correlations) from existing papers. The references associated with these granitic fields are as follows: MORB: Stern et al. (1995), Volker et al. (1993) and a culled data base from Melson et al. (2002). I-type: Egypt (Moghazi, 2002), Israel (Beyth et al., 1994), Oman (Gass et al., 1990) and Sudan (Klemenic and Poole, 1988). Fractionated A-type: Egypt (El-Sayed et al., 2002), Israel (Beyth et al., 1994) and Jordan (~250 data points from Jarrar et al., 2003 and Jarrar et al., 2008) Within Plate Granite: Egypt (Abdel-Rahman and Martin, 1990; El-Baily and Streck, 2009; Katzir et al., 2007), Israel (Mushkin et al., 2003), Sudan (Harris et al., 1983) and Yemen (Coleman et al., 1992; El-Gharbawy, 2011).
This section aims to identify major and trace element discriminators that constrain the separation of identified island arc, synorogenic, post-orogenic and anorogenic age granitoids in Chapter 3. The sampled Arabian Shield suites described in Chapters 2 and 3 are divided into the following subheadings: 1) Island Arc and Syncollisional Granitoids (IA+Syn). These contain the oldest ages and most mafic suites; 2) Nabitah and Halaban Suture Granitoids (NHSG). These intrude the Nabitah and Halaban Sutures and are further subdivided into NHSG (fractionated) and NHSG (non-fractionated); 3) Post-Orogenic Perthitic Granitoids (POPG). These contain ages of <636Ma->600Ma, aegirine absent mineralogy and are spatially juxtaposed to suture zones; and 4) Anorogenic Aegirine Perthitic Granitoids (AAPG). These are <600Ma, aegirine-bearing and are spatially isolated within plate granites. The spatial relationships used to categorise these groups can be observed in Figures 1.2-1.4.
98 4.2.1 Island Arc and Syncollisional Granitoids (IA+Syn).
The IA+Syn suites are the oldest granitoids (845-693Ma) sampled in the Arabian Shield and contain the most mafic mineralogy (Chapters 2 and 3 respectively). This group includes the Makkah Suite, Shufayyah Complex, Jar-Salajah Complex and the felsic volcanics of the Subh Suite. However, the 600Ma Rithmah Complex is also included in this group because of its similar mafic mineralogy. All suites are strictly confined to the western side of the Shield, mostly concentrated in the Hijaz terrane (Figure 4.16). In consequent of their age, mineralogy and subduction setting, these intermediate granitoids create an ideal proxy for mantle derived suites and a close affinity with MORB fields. The major and trace element values are summarised in Tables 4.2 and 4.3 and displayed in entirety in Appendix 5.
Major Element Geochemistry
Plutons in this group contain some of the lowest and highest values of major element concentrations of all Arabian Shield granitoids. The IA+Syn samples are predominately intermediate containing ~64% SiO2, with the younger more fractionated
Jar-Salajah Complex at ~73%. Total alkalis (Na2O+K2O) are the lowest of all granitoids ranging from ~6.2-6.8 wt% with negligible differences between suites. By contrast, CaO values are amongst the highest of all suites ranging from ~2-4wt%. Other distinguishable features are high TiO2 and Mg# values of ~0.2-0.7wt% and ~0.28-0.58 respectively. The Makkah Suite and Rithmah Complex samples contain lower SiO2 and total alkali values ranging from ~51-57wt% and ~3.9-5wt% respectively, but correlate with amongst the highest values of Mg# (~0.51-0.43), TiO2 (~0.65-1.3 wt%) and CaO (~7.2-8.5 wt%) of any samples analysed in the Shield.
Both the granitic and mafic units of the IA+Syn group are easily distinguished from all other Arabian suites by simply utilising major elements as discriminators. As illustrated in Figure 4.1, SiO2 is plotted against MgO, Na2O+K2O and FeO and clearly separates these suites from more evolved felsic POPG/AAPG samples. It is interesting that these continuously display fractionation trends from the MORB like field through
99 the I-type zone. The least evolved mafic suites such as the Rithmah Complex have a strong affinity with the MORB. More evolved suites such as the Jar-Salajah Complex mingle at the base of fractionated/within plate field, but are distinctly separated from these perthitic suites (Figure 4.1).
Figure 4.1 part1: Hawker diagrams of 19 suites sampled in the Arabian Shield. Top) MgO vs. SiO2 illustrating fractionation trends of the NHSG (fractionated) mafic samples from a MORB source to felsic aegirine perthitic products. These follow a similar trend to the older green syncollisional suites, but produce aegirine-bearing endmembers identical to AAPG suites. Bottom) Na2O + K2O vs. SiO2 demonstrating the lateral fractionation of the POPG and AAPG syenitic endmembers compared to the MORB style fractionation curve experienced by the NHSG (fractionated) samples. Both trends arrive at the same aegirine perthitic zone and as discussed in Chapter 7, they are derived from differing mantle sources. References for the published MORB, Arabian-Nubian Shield I-type, fractionated A-type and WPG data fields and sample suite abbreviations are displayed in Chapter 4.2. All geochemical data are displayed in Appendix 5.
100 Trace Element Geochemistry
IA+Syn suites are easily discriminated with both major and incompatible trace element concentrations. Excluding NHSG (fractionated) mafic samples, these generally contain the lowest concentrations of Nb (<5 ppm), Rb (<50 ppm), Ga (~12-20 ppm), Nd (~15-25 ppm) and Y (~15-50 ppm) of any granitoid sampled in the Arabian Shield. Interestingly, the lowest and highest values correspond with the youngest Rithmah Complex mafics and oldest Makkah Suite tonalites respectively.
Figures 4.2 and 4.3 display the repetitive fractionation trend exhibited by the IA+Syn fields. These are continuously separated from perthitic samples including the most evolved Jar-Salajah Complex unit that resides outside any POPG or AAPG fields. This fractionation from MORB like affinities to silica rich samples is very prominent when using silica against any incompatible elements (Figure 4.2). The low incompatible concentrations, including the most evolved samples (similar silica values to POPG/AAPG), clearly suggests a differentiated mantle source from younger POPG and AAPG suites.
Highlighted in Figure 4.3, the IA+Syn suites have a strong affinity for plagioclase rich melts and low Rb values. The incompatible nature of Rb creates tendencies for it to reside in the melt phase as indicated by the fractionated suture related suites. The IA+Syn suites show minimal fractionation and are confined to the plagioclase rich field. LREE elements are somewhat redundant for separating IA+Syn suites from the remaining suites because this has been clearly established simply using major elements. However, they provide supporting evidence for MORB like mantle chemistry and fractionate in a similar manner to NHSG suites.
This is quite evident when using Nb and Nd parameters (Figure 4.3). These suites are only moderately fractionated as exhibited by their low Ce/Yb (~10-20) and Y/Nb (~4-7) values. They have a close association with the suture related suites and although they seemingly could also produce aegirine-bearing endmembers with increased fractionation, this seems highly unlikely. The IA+Syn suites also contain evolved samples with ~70% SiO2, but are clearly not POPG or AAPG endmembers both
101 geochemically and mineralogically. The common MORB like affinity that links these suites together is discussed further in Chapter 7.2.
Figure 4.1 part2: Hawker diagrams of 19 suites sampled in the Arabian Shield. Top) FeO vs. SiO2 displays a reduction in iron content with increasing silica content. This helps separate the majority of NHSG (fractionated) samples from remaining POPG/AAPG suites. There is also a rapid increase in iron content from ~45-55% SiO2, which possibly correlates with magnetite crystallisation. Bottom) K2O vs. Na2O highlighting the Na/K rich nature of POPG and AAPG granitoids. The fractionation experienced by NHSG (fractionated) samples are interrupted by the onset of black NHSG (non-fractionated) suites interpreted to be a change in mantle chemistry (Chapter 7.2). References for the published MORB, Arabian-Nubian Shield I-type, fractionated A-type and WPG data fields and sample suite abbreviations are displayed in Chapter 4.2. All geochemical data are displayed in Appendix 5.
The Makkah Suite and Rithmah Complex (western Shield) contain mafic endmembers which require the comparison of their trace element signatures against N- type MORB mantle and younger POPG/AAPG syenites of similar age to provide insight into their mantle source. These are both illustrated in Figure 4.4. Firstly, it
102 should be noted that the Makkah Suite is a product of island arc type magmatism with and age of 867Ma (Chapter 3), hence with the exception of the Paleoproterozoic Khida terrane, any crustal contamination must be older than any Arabian Shield terrane.
Figure 4.4 illustrates the similarities between the Makkah Suite and typical N- type MORB. In general, this shows a slight LREE enrichment, but particularly in the middle REE. This shows a slowly downward trending depletion in HREE reaching N- MORB like levels. This is attributed to high levels of hornblende and pyroxenes in its mineralogy (Chapter 2). Most notable are the strong Th and Nb anomalies which are synonymous with contamination and incompatibility during fractionation processes. There are also no Eu or Sr anomalies suggesting minimal early feldspar crystallisation. The age of this suite rules out young continental crust as a contaminant, possibly suggesting older Paleoproterozoic crust. This is discussed further in Chapter 7.
By contrast, the 600Ma Rithmah Complex shows REE patterns almost identical to N-MORB (Figure 4.4). This suite is compared to the enriched syenitic samples that produce perthitic POPG and AAPG endmembers. This clearly shows no enrichment in LREE or HREE almost skirting the N-MORB signature to perfection. Nb and Pb show slight negative anomalies, but nothing substantial to discriminate magmatic processes.
Overall, this Rithmah Suite suggests an N-MORB source that was rapidly brought to the surface to a within plate rift setting (Chapter 7.4). IA+Syn samples that are >60 wt% SiO2 are compared with average crustal compositions in Figure 4.5, which includes the most evolved (~70 SiO2 wt%) Jar-Salajah Complex. Surprisingly, these suites show an almost flat linear REE pattern not typical of syncollisional suites. These clearly plot within the syncollisional field and show no overlapping with AAPG zones above. The IA+Syn samples contain no obvious anomalies, but show marginal negative Nb, Th and Eu anomalies synonymous with contamination and feldspar fractionation processes. The age of these suites in combination with their N-MORB classified mafics and characteristics, suggests contamination of N-MORB mantle source. The tectonic significance of this is discussed further in Chapter 7.
103 4.2.2 Nabitah and Halaban Suture Granitoids (NHSG).
Granitoids that define this group are emplaced into suture zones such as the Nabitah and Halaban Sutures. These post-tectonic (<636->600Ma) suites have been separated further into two groups based on mineralogy: NHSG (fractionated) which includes the Al Hafoor and Kawr Suites that contain the oldest ages of 636Ma and also analysed mafic, intermediate and felsic (some aegirine-bearing) endmembers (Chapter 2); NHSG (non-fractionated) which includes the Ibn Hashbal Suite, Najirah Granite and Wadbah Suite which are slightly younger (618Ma) than NHSG (fractionated) intrusions. These produce similar perthitic products (Chapter 2), but more importantly, contain no evidence of fractionation or mafic mingling. The major and trace element values are summarised in Tables 4.2 and 4.3 and displayed in entirety in Appendix 5.
Major Element Geochemistry
NHSG (fractionated) suites are the most tectonically and geochemically interesting of all granitoids sampled in the Shield. The plutons are emplaced into the complex interplay of oceanic and continental crust underneath the Nabitah Suture. Understandably, this produces a wide range in major element geochemistry. The granitoids are predominantly felsic ranging from ~67-76 wt% SiO2 with the highest values corresponding with the Al Hafoor Suite. Similar to the AAPG suites, these units contain low Al2O3 (~10.7-14.7 wt%), TiO2 (~0.09-0.76 wt%), Mg# (~0.15-0.42) and CaO (~0.5-2.5 wt%) concentrations and high total alkalis (7.3-9 wt%). Interestingly, most high and low values correspond with the Kawr Suite. One distinguishable feature of these granitoids is their high Fe# (~0.58-0.85), which are amongst the highest in the Shied. Once again, the highest and lowest values correspond with the Kawr Suite.
The Al Hafoor and Kawr Suite mafics will be compared to the IA-Syn mafics to gauge similarities in parent source composition. NHSG (fractionated) mafics contain the lowest and highest range in SiO2 content (~45-60 wt%) of any suite sampled in the Shield. Interestingly, the highest and lowest values are clearly separated from the IA+Syn mafics in all major element fields. This is especially pronounced with CaO
104 (~4.7-16.4 wt%), Al2O3 (~13.9-25.3 wt%) and Fe# (~0.24-0.82) concentrations, but is also evident with total alkalis (~0.59-6.5 wt%), TiO2 (~0.08-1.8 wt%) and Mg# (~0.18- 0.76) values. Although the Kawr Suite correlates with the lowest and highest endmembers, the Al Hafoor Suite is also at the higher end of the spectrum. The petrogenetic significance of these differentiated NHSG (fractionated) and IA+Syn suites is discussed further in Chapter 7.2.
NHSG (non-fractionated) granitic suites are also geochemically interesting because they define a change in mantle behaviour reflected in their slightly younger age in the Nabitah Belt. These suites exhibit no mafic endmembers or extensive fractionation trends displayed by NHSG (fractionated) suites. NHSG (non-fractionated) suites are amongst the most felsic granitoids sampled ranging from ~71-75 wt% SiO2. Aside from the POPG and AAPG syenites, they also contain the highest total alkalis (~8.5-9.4 wt%). The highest values correspond with the youngest samples of the
Wadbah Suite. Interestingly, these suites contain the lowest values of TiO2 (~0.15-0.3 wt%) and CaO (~0.4-1.6 wt%) of any felsic granitoids sampled in the Shield. Other distinguishable features include high Fe# values (~0.82-0.94) that are amongst the highest of all suites sampled in the Shield. Once again the highest values correlate with the youngest samples of the Wadbah Suite.
One of the most obvious features displayed in Figure 4.1 is the strong fractionation trend from MORB to AAPG fields exhibited by NHSG (fractionated) suites. Although the felsic endmembers are indistinguishable from other perthitic POPG/AAPG granitoids, no other suites display such striking fractionation trends. The use of major elements such as SiO2 and alkali contents clearly discriminate NHSG (fractionated) mafic-intermediate endmembers from other granitic suites. These show a distinct enrichment of alkali content with increasing silica and follow a similar fractionation path to that of IA+Syn suites originating at the MORB field (Figure 4.1). This trend is again illustrated using MgO and FeO, but rather a decrease in content with increasing silica.
Most importantly, NHSG (fractionated) mafics clearly originate from a different mantle source than that of primitive POPG and AAPG syenitic samples. NHSG (fractionated) mafics are very low in alkalis compared to alkali rich POPG/AAPG suites
105 with similar silica content. This is again clearly displayed when using only Na2O and
K2O parameters. The obvious differences in mantle fractionation that generate similar felsic perthitic products are discussed further in Chapter 7.2.
Plutons correlating with NHSG (non-fractionated) suites are easily placed into the AAPG field realm and show no evidence of fractionation (Figure 4.1). The generation of these suites seems to correlate with a change in mantle chemistry exhibited by the NHSG (fractionated) Kawr Suite. The transition from N-MORB mafics and intermediate granites to iron rich aegirine-bearing alkali-granites (coinciding with the appearance of NHSG (non-fractionated) suites) is thought to resemble slab roll back processes and is discussed further in Chapter 7.3. Felsic units from both NHSG groups are not distinguishable from other POPG/AAPG suites using major element parameters alone. This suggests the necessity for the use of incompatible elements to separate further these groups and will be discussed shortly.
Trace Element Geochemistry
Similar to the IA+Syn suites, the nature of NHSG (fractionated) samples creates an easily discriminated cluster of data when utilising SiO2 parameters. However, as mentioned above, the felsic endmembers of both NHSG groups are not separated easily from similar perthitic POPG or AAPG suites. This warrants further discrimination using incompatible trace elements.
NHSG (fractionated) suites contain the most mafic and felsic units sampled in the Shield, hence the lowest and highest values of any sample. Unsurprisingly, the granitic endmembers have the highest values of Nb (~20-50 ppm), Rb (~100-175 ppm), Ga (~20-30 ppm), Nd (~40-120 ppm) and Y (~30-100 ppm). Conversely, the mafics yield the lowest values of Nb (~<5-20 ppm), Rb (~<10-100 ppm), Ga (~10-20 ppm), Nd ~(<5-40 ppm) and Y (~<5-30 ppm). The lowest and highest values correspond with the Kawr Suite with the Al Hafoor on the lower end of the spectrum. NHSG (non- fractionated) suites contain similar concentrations of Nb (~5-20 ppm), Rb (~50-175 ppm), Ga (~15-25 ppm), Nd (~20-120 ppm) and Y (~10-95 ppm) to that of NHSG
106 (fractionated) felsic endmembers. The majority of the highest values correspond with the youngest Wadbah Suite samples. Most importantly, only Nb and Y values of both NHSG groups correlate with similar levels observed in AAPG suites.
Figure 4.2 part1: Hawker diagrams of 19 suites sampled in the Arabian Shield. Top) Zr/ TiO2 vs. SiO2 highlights the fractionation curve produced by the blue NHSG (fractionated) suites mimicking that of the IA+Syn suites. Clearly AAPG suites contain the highest concentrations of Zr, but unlike the NHSG (fractionated) aegirine endmembers, it is suggested AAPG are not a product of subduction style processes (Chapter 7). Bottom) Nb vs. SiO2 illustrates the importance of Nb to discriminate the AAPG and NHSG (fractionated) aegirine endmembers from the remainder of the POPG. The IA+Syn suites follow a straight fractionation pattern at the bottom with perthitic POPG at their termination. Some NHSG (fractionated) perthitic endmembers are also situated here and possibly represent different mantle processes than that of the AAPG/NHSG (fractionated) aegirine-bearing alkali-granites (Chapter 7.2). References for the published MORB, Arabian-Nubian Shield I-type, fractionated A-type and WPG data fields and sample suite abbreviations are displayed in Chapter 4.2. All geochemical data are displayed in Appendix 5.
107 Closer examination of the incompatible elements reveals some interesting trends when plotted against silica content. Figure 4.2 highlights the strong fractionation trends exhibited by the NHSG (fractionated) suites. These originate in the MORB field and display an increase in incompatible concentration with increasing SiO2. This fractionation trend appears to mimic the IA+Syn suites, but appears to separate around
60 wt% SiO2. This is most obvious when using Ga. Interestingly, the NHSG (non- fractionated) suites appear to mingle with NHSG (fractionated) granitoids just prior to the onset of the AAPG field. This is most noted when using Zr/ TiO2, Rb and Ga values (Figure 4.2). Nb appears to separate NHSG (fractionated) and NHSG (non- fractionated) endmembers quite well. NHSG (fractionated) suites fractionate from the MORB zone and continue into the AAPG field, whilst NHSG (non-fractionated) suites are clustered with IA+Syn and POPG suites near the high SiO2, low trace element zone.
Although the use of incompatible elements with SiO2 allows a clear distinction between POPG suites, it unfortunately doesn’t allow the discrimination between similar AAPG suites. The most evolved, hence most fractionated NHSG (fractionated) samples show significant overlap into the AAPG field. This is likely attributed to their similar aegirine mineralogy. However, these clearly show different mantle geochemistry as highlighted in Figure 4.3. For the first time thus far, both NHSG groups are easily separated from AAPG suites when utilising incompatible elements. Most notable is Nb plotted against Y and Nd, which clearly exhibit a strong fractionation trend from MORB like affinities to highly evolved aegirine-bearing suites. This line includes both NHSG groups, POPG and IA+Syn suites. The aegirine-bearing AAPG are isolated from all suites, suggesting a different mantle source. Fractionation trends run parallel with the AAPG suites, but never overlap at any point. This creates an ideal classification scheme for A-type granitoids, which is discussed further in Chapter 7.
As previously highlighted, there is significant overlap between aegirine-bearing NHSG (fractionated) suites and aegirine-bearing AAPG suites (Figure 4.2). This places doubt on the probability that AAPG suites are an isolated, relatively unfractionated field. One might argue that they are the end product of intense fractionation similar to NHSG (fractionated) suites. However, the use of element ratios, Ce/Yb and Y/Nb in particular, sheds some light on this process. As illustrated in Figure 4.3, both NHSG groups contain a large range in values. NHSG (fractionated) granitoids correlate with
108 Figure 4.2 part2: Hawker diagrams of 19 suites sampled in the Arabian Shield. Top) Rb vs. SiO2 conveys a clear separation of the AAPG suites from POPG and NHSG (fractionated) suites. This is most likely due to the plagioclase rich mineralogy of the mafic endmembers and plagioclase poor felsic endmembers. Bottom) Ga vs. SiO2 displays an interesting boomerang shaped curve from the mafic NHSG (fractionated) samples through the IA+Syn suites and finally down to the felsic POPG. The AAPG suites and NHSG (fractionated) aegirine endmembers clearly are separated from this zone. This is interpreted to be the result of enriched mantle and is discussed further in Chapter 7.2. References for the published MORB, Arabian- Nubian Shield I-type, fractionated A-type and WPG data fields and sample suite abbreviations are displayed in Chapter 4.2. All geochemical data are displayed in Appendix 5. the highest Ce/Yb (~20-120) and Y/Nb (~1-2) ratios of any suite sampled in the Shield. Interestingly, NHSG (non-fractionated) samples are also amongst the highest with values of ~10-120 and ~2-6. NHSG (fractionated) mafics are unsurprisingly low with values of ~10-20 and ~2-7 and closely mimic the IA+Syn fields. Most importantly, both NHSG (fractionated) and IA+Syn suites illustrate high levels of fractionation and are clearly isolated from unfractionated AAPG fields (left hand side of Figure 4.3). Also
109 worth noting is the strong presence of NHSG (non-fractionated) suites confined towards the most evolved NHSG (fractionated) suites. Overall, the fractionation and MORB like affinity displayed by both NHSG groups is clearly separated from AAPG suites. This significance is discussed further in Chapter 7.2.
The affiliation of NHSG (fractionated) mafics with N-MORB (Figures 4.1-4.3) shows fractionation trends that produce both perthitic (Al Hafoor and Kawr Suite) and aegirine-bearing perthitic (Kawr Suite) endmembers. As described above, the latter contains similar trace element behaviour to AAPG suites. It was therefore felt necessary to compare the trace element distribution patterns of NHSG (fractionated) mafic endmembers with N-MORB type mantle. These are plotted in Figure 4.4.
NHSG (fractionated) mafics display a relative enrichment in LREE and a slow downward depletion in HREE to N-MORB type levels. These mafics also share a large negative Nb and positive U, Pb anomalies synonymous with crustal contamination. The older Al Hafoor Suite shares a very close affinity with N-MORB, particularly in the middle REE, but is slightly more depleted in HREE. This is attributed to the pyroxene, amphibole and spinel dominated mineralogy (Chapter 2). By contrast, the Kawr Suite covers a large range in concentrations covering vast sections of both N-MORB and E- MORB fields. This is particularly noticeable in the LREE and HREE containing almost 10 times the concentration of both N-MORB and the Al Hafoor Suite. This suite also contains a slight Eu anomaly that is absent in the Al Hafoor Suite, which is suggestive of feldspar fractionation processes. This large range in REE exhibited by the Kawr Suite mafics seems to reflect the N-MORB fractionation. Overall, these similar mafic suites fractionate to produce perthitic (Al Hafoor and Kawr Suite) and aegirine perthitic suites (Kawr Suite). The petrogenetic implications of these mafics are discussed further in Chapter 7.3.
Both NHSG groups, excluding the mafics described above, are plotted against each other to examine their similarities produced from two clearly different sources. One of the most striking features of Figure 4.5 is the distribution of suites in relation to the published enriched WPG field. The Al Hafoor Suite is clearly well below this field and produces similar patterns to its N-MORB like mafic endmember (described above). Most notable are the large negative Nb and positive U and Pb anomalies which extend
110 into the lower parts of the WPG field. It also has a distinct positive Sr anomaly and a flat LREE/HREE pattern absent of Eu anomalies. These are all symptomatic of crustal contamination with negligible fractionation processes.
By contrast, the Kawr and NHSG (non-fractionated) suites display almost the opposite of every anomaly observed in the Al Hafoor Suite (Figure 4.5). These have strong Sr and Eu anomalies, which are attributed to high levels of plagioclase fractionation. However, they also share the same negative Nb anomaly associated with crustal contamination. Most notable is the ~10 fold increase in LREE and HREE. This clearly separates these from the Al Hafoor Suite and places them a considerable distance into the published WPG field. Interestingly, the more evolved NHSG (non- fractionated) suites occur after the Al Hafoor Suite and show a close affinity with the Kawr Suite aegirine endmembers (extends into the WPG realm). The obvious difference between NHSG (fractionated) and NHSG (non-fractionated) suites highlights a change in mantle chemistry beneath the Nabitah Belt and is discussed further in Chapter 7.3.
4.2.3 Post-Orogenic Perthitic Granitoids (POPG).
This selection of granitoids incorporates suites that are juxtaposed or sandwiched between suture zones (Figures 1.2-1.4). These are amongst the youngest samples in the Arabian Shield (<636Ma) and share similar perthitic mineralogical traits with the surrounding AAPG suites, but are deprived of Na-rich amphiboles (Chapter 2). This group includes the Admar Suite, Haml Suite, Idah Suite and Al Khushaymiyah Suite. The crustally derived garnet-bearing Malik Granite is also included here as it intrudes the Idah Suite. The major and trace element values are summarised in Tables 4.2 and 4.3 and displayed in entirety in Appendix 5.
Major Element Geochemistry
POPG suites contain similar, but slightly lower major elements to AAPG samples and are predominantly intermediate to felsic in nature (~63-75wt% SiO2).. This
111 of course excludes the syenitic Admar Suite which will be described shortly. The lowest and highest values correlate with the Al Khushaymiyah Suite and Idah Suite samples respectively. These represent the least and most mineralogically evolved granitoids sampled in the eastern Shield. One of the most interesting aspects of the POPG suites is their geochemical similarities with similar age AAPG. This is most noted in their CaO
(~0.4-2.7 wt%), TiO2 (~0.05-0.45 wt%) and Fe# (~0.59-0.87) concentrations. With the exception of Fe#, the lowest and highest values correspond with the Haml and Al Khushaymiyah Suite respectively. Unsurprisingly, the crustal Malik Granite contains almost identical compositions to that of the Idah Suite into which it intrudes.
Two parameters that separate the POPG and AAPG are the slightly higher total alkali content (~8.6-9.7 wt%) and much higher Al2O3 (~12.9-17.9 wt%) displayed by the POPG suites. This possibly correlates with the biotite rich mineralogy exhibited by the POPG samples (Chapter 2). However, POPG suites also contain perthitic rich mineralogies similar to AAPG suites, thus creating difficulties in discriminating the two group types based on major elements alone. The highest and lowest values correspond with the older least evolved Haml Suite and younger more evolved Idah Suite.
Similar to the AAPG Mardabah Complex syenite, the Admar syenite also represents the most primitive endmember in the POPG group at ~60 wt% SiO2. This suite is separated from the Mardabah Complex by its older age (600Ma) and widespread, arc style emplacement (juxtaposed to suture zones). The Admar Suite contains the highest total alkali values (~11-11.2 wt%) of any granitoid sampled in the
Arabian Shield. This is also true for the Al2O3 values of ~18.3-18.5 wt%. One of the most prominent features that distinguish the POPG syenite from the AAPG syenite is the much lower Fe# (~0.63) and also higher Mg# of ~0.37 and TiO2 value of ~0.85-0.93 wt%, but has slightly lower CaO values of 2.2-2.3 wt%.
Major element characteristics of both POPG and AAPG suites are similar, therefore not easily discriminated using major element plots. This becomes increasingly obvious when using parameters such as MgO or FeO (Figure 4.1). However, some trends are identified when using SiO2 with alkali elements. Similar to the Mardabah Complex, the POPG syenite is most primitive and represents the least fractionated and most mantle like geochemistry from which fractionation occurs. This is apparent in
112 Figure 4.1, illustrating a lateral style fractionation trend that is distinct from MORB trends exhibited by the NHSG (fractionated) suites. The POPG units also contain some of the highest Na2O values (~4-5 wt%) separating them from all other granitoids (Figure 4.1). However, similar POPG and AAPG geochemical processes cannot easily be distinguished using major elements alone.
Figure 4.3 part1: Hawker diagrams of 19 suites sampled in the Arabian Shield. Top) Na2O + K2O vs. Rb highlight the transition of plagioclase rich mafic endmembers to plagioclase poor felsic granitic endmembers. Note that there are two trends displayed in this figure: a) the fractionation curve produced by the NHSG (fractionated) suites; and b) the lateral fractionation from the AAPG olivine syenites to felsic AAPG alkali-granites. Rb is a highly incompatible element that resides in the melt, hence is an excellent monitor for fractional crystallisation. Both trends produce aegirine-bearing endmembers and as discussed in Chapter 7, they are the products of two differing mantle processes. Bottom) Nb vs. Nd exhibits the discrimination of AAPG suites from the remainder of the perthitic suites. This is used as a potentially new A-type mantle source classification scheme (Chapter 4.4.4b). References for the published MORB, Arabian-Nubian Shield I-type, fractionated A-type and WPG data fields and sample suite abbreviations are displayed in Chapter 4.2. All geochemical data are displayed in Appendix 5.
113 Trace Element Geochemistry
As mentioned above, similar major element trends exhibited by both POPG and AAPG suites cause difficulties in separation. Figures 4.2 and 4.3 utilise incompatible elements that clearly distinguish these two suites. POPG suites contain amongst the lowest concentrations of Nb (~5-15 ppm), Rb (~100-150 ppm), Ga (~15-20 ppm), Nd (~10-40 ppm) and Y (~10-25 ppm) of any granitoid sampled in the Arabian Shield. The lowest and highest values correspond with the least evolved Admar Suite syenite and most evolved Idah Suite alkali-granite. Interestingly, these levels appear to correlate with IA+Syn values and become significantly mingled in their field when using Nb, Ga and Nd incompatible elements (Figures 4.2 and 4.3).
The use of LILE and HFSE elements such as Rb and Zr are limited for separation because POPG suites still display some overlap with the less evolved AAPG endmembers (Figure 4.2). These elements partially separate the IA+Syn and NHSG samples, but do not appear to clearly differentiate the primitive POPG and AAPG syenites. However, Nb and to a lesser extent Ga, clearly discriminate the two syenites by a few orders of magnitude. These reflect clear differences in mantle chemistry which fractionate to similar perthitic mineralogy. This is illustrated further by the spider plots, which will be described shortly. Most importantly, Nb and Ga clearly separate the POPG and AAPG suites of similar age.
This trend for the POPG suites to become increasingly dissimilar to the AAPG is demonstrated in Figure 4.3. As mentioned above, the Nd and Y values are quite low and reflect almost MORB like values. The POPG suites plot exclusively with the IA+Syn and NHSG suites and are isolated from elevated AAPG suites (including similar syenites). These show an obvious fractionated trend from the MORB like realm.
Even the most evolved POPG Idah suite (~70-75 wt% SiO2) only correlates with the most primitive AAPG syenites in the above field (Figure 4.3). The extent of fractionation exhibited by POPG suites is somewhat mimicked by the IA+Syn suites using Nd values. However, Y clearly shows a lower angled path of fractionation for the IA+Syn suites with the POPG samples plotting along the same fractionation trend as NHSG granitoids.
114 Figure 4.3 part2: Hawker diagrams of 19 suites sampled in the Arabian Shield. Top) Nb vs. Y allows the discrimination of the contaminated N-MORB like products and AAPG aegirine alkali-granites. AAPG samples clearly have an enrichment in Nb compared to all other perthitic granitoids and is interpreted to be a product of lithospheric processes (Chapter 7.6). This diagram forms the basis for the A-type mantle classification scheme discussed in Chapter 4.4.4b. Bottom) Ce/Yb vs. Y/Nb highlights the importance of discriminating fractionation. Many other figures illustrate AAPG samples at the termination phases of felsic fractionation, hence place doubt on their unfractionated nature. This set of ratios clearly shows POPG and NHSG samples continue to fractionate well past the AAPG realm. References for the published MORB, Arabian-Nubian Shield I-type, fractionated A-type and WPG data fields and sample suite abbreviations are displayed in Chapter 4.2. All geochemical data are displayed in Appendix 5.
The fractionation exhibited by POPG suites are separated further from both AAPG and IA+Syn suites by utilising Ce/Yb and Y/Nb element ratios (Figure 4.3). These values are ~15-80 and ~1.5-3 respectively and are clearly higher than AAPG suites. Once again, the highest values correspond with the primitive syenite. The POPG samples are convincingly isolated from the AAPG zone and display evidence of minor
115 fractionation not observed in the AAPG suites. It is apparent that POPG and NHSG suites are mineralogically and geochemically linked, thus sharing the same fractionation trends. However, the absence of Na-rich amphiboles in POPG suites confines this group to the more intermediate samples of the NHSG field. The degree and significance of this fractionation is discussed further in Chapter 7.2.
The similar age, mineralogy and geochemical parameters of primitive POPG and AAPG syenites warrants further trace element investigation. These resemble the least evolved and most MORB like endmembers from which fractionation to felsic products occurs. The spider distribution of trace elements of these two mantle sources is illustrated in Figure 4.4. These are plotted against the similar age IA+Syn Rithmah Complex (600Ma) for a reference sample similar to an N-MORB mantle signature.
Overall, the POPG syenite exhibits very similar enrichment patterns to the AAPG syenite. There is a strong enrichment of LREE, followed by a moderate depletion in HREE to N-MORB like levels. This depletion in attributed to the presence of early formed zircon crystals. The most striking difference between the two syenites is the strong negative Nb and Th anomalies associated with the POPG syenite. This is also coupled with positive U, Pb and Eu anomalies synonymous with early hornblende crystallisation. Most importantly, the Nb, Th, U and Pb anomalies are convincingly attributed to crustal contamination. This creates an obvious difference between the two syenites sources, hence petrogenesis and is discussed further in Chapter 7.4.
All POPG suites, excluding the syenite, are also plotted against AAPG suites to differentiate the evolved nature of the felsic endmembers. One of the most striking differences is the lower LREE and HREE abundances displayed by the POPG suites (Figure 4.5). These do not enter the AAPG field, but plot in a similar trend to IA+Syn suites. Note that this is not depletion in trace elements, but rather the AAPG suites are simply much higher in element concentrations. This is also not attributed to mineralogy differences because both contain similar perthitic mineralogy (Chapter 2).
The absence of aegirine is possibly reflected in the slight depletion in middle REE (Nd-Zr). The POPG suites contain strong negative Sr, Eu, P, Ti, and Ba anomalies synonymous with plagioclase fractionation/removal from the melt. Similar to the POPG
116 Figure 4.4 part1: N-MORB normalised REE patterns of whole rock samples <60% SiO2. These are the most primitive endmembers of the granitic suites and are thought to represent the parent magmas from which the felsic products are derived. A) Island arc units from the Makkah Suite (Jiddah terrane) with a contaminated N-MORB like signature. B) Nabitah mafic endmembers (purple=ao, blue=kw) with a strong negative Nb anomaly and HREE depletion, but enrichment of LILE, suggesting contamination of N-MORB like mantle. C) Syenitic orange POPG (ad) and red AAPG (mr) endmembers compared to similar age Rithmah N-MORB gabbro (green). POPG and AAPG syenites are clearly elevated in both LILE and lighter HREE and are themselves separated by large Nb/TH/Pb anomalies. The evolution of enriched vs. contaminated mantle is discussed further in Chapter 7. References for the published MORB data fields and sample suite abbreviations are displayed in Chapter 4.2. Samples were normalised to N-MORB values from Sun and McDonough (1989). syenite, the POPG granitoids contain a strong Nb depletion absent in the AAPG suites. This once again points to the possibility of crustal contamination. Despite interpretation, there is a clear difference in mantle chemistry. POPG suites produce a
117 flat linear looking trace element pattern much lower in abundance, but produce similar perthitic endmembers. The significance of these chemical differences and their role petrogenesis is discussed further in Chapter 7.
Figure 4.4 part2: N-MORB normalised HREE patterns of whole rock samples <60% SiO2. These are the most primitive endmembers of the granitic units and are thought to represent the parent magmas from which the felsic products are derived. A) Island arc units (Jiddah terrane) with a contaminated N-MORB like signature. B) Nabitah mafics (purple=ao, blue=kw) indicate N-MORB pattern (purple) and slightly enriched source (blue), possibly related to changing mantle beneath the Nabitah Belt (Chapter 7.3). C) Syenitic POPG and AAPG endmembers compared to similar age Rithmah N-MORB gabbro. Both are LILE enriched, but the APPG is slightly more enriched in HREE and produces enriched mantle derived granitoids (Chapter 7). References for the published MORB data fields and sample suite abbreviations are displayed in Chapter 4.2. Samples were normalised to N-MORB values from Sun and McDonough (1989).
118 4.2.4 Anorogenic Aegirine Perthitic Granitoids (AAPG).
AAPG suites are defined by both their distinct isolation from plate boundaries and anorogenic crystallisation ages (<600Ma). These economic granitoids include the Abanat Suite, Al Bad Granite Super Suite, Al Hawiyah Suite, Ar Ruwaydah Suite and the Mardabah Complex. These exhibit perthitic, aegirine-bearing mineralogy (Chapter 2), but display no obvious fractionation trends. Major and trace element values are summarised in Tables 4.2 and 4.3 and displayed in entirety in Appendix 5.
Major Element Geochemistry
AAPG suites are amongst the most felsic samples ranging from 71-78 wt% SiO2 with the highest and lowest values correlating with the Al Bad and Al Hawiyah Suites respectively. One monzonitic sample from the Al Hawiyah Suite contains lower silica at
~65%. Unsurprisingly, this contains the highest TiO2 (~0.98 wt%) and CaO (~2.86wt%) concentrations, but is similar to more felsic endmembers in other parameters. Apart from the Mardabah Complex, which will be described shortly, all other granitoids contain amongst the highest total alkali values of ~7.8-8.5 wt%.
These suites also contain amongst the highest Fe# (~0.72-0.95) of any granitoids sampled in the Shield. It should be noted these values are of similar levels to that of both NHSG group felsic endmembers. This trend continues with low TiO2 (~0.05-0.25 wt%), Al2O3 (~10.1-14.1 wt%) and CaO (~0.25-1.2 wt%). The majority of the highest and lowest values correlate with the Al Hawiyah and Al Bad Suites respectively.
Interestingly, the lowest Al2O3 values correspond with the economic Abanat Suite.
The Mardabah Complex is the most primitive endmember at ~60 wt% SiO2, which correlates with its relatively unfractionated olivine syenitic nature (Chapter 2). This is included because of its anorogenic age (525Ma), tectonic setting and similar perthitic mineralogy. These contain the highest alkali (~9.8 wt%), Al2O3 (~18-18.5 wt%) values of any granitoid in the Arabian Shield. Similar to the POPG syenite, this contains high CaO (~2.9-3.2 wt%), TiO2 (~0.7-0.8 wt%) and Mg# (~0.25). AAPG and
119 POPG syenites are separated based on their Fe#. The Mardabah Complex is low in
SiO2, but enriched in other parameters, thus is used as a proxy for enriched mantle from which fractionation to felsic AAPG suites are derived. This will shortly become very clear when describing the trace elements.
Interestingly, the high major element values are possessed by all NHSG, AAPG and POPG felsic endmembers. This seemingly creates the use of major element discriminators somewhat redundant for geochemical separation. However, as illustrated in Figure 4.1, these AAPG suites commonly form the termination phases of data clusters. This becomes obvious when using major elements such as FeO and total alkali, where the most evolved AAPG endmembers are separated from all other samples. Most importantly, these suites can be clearly separated from IA+Syn MORB like granitoids.
The separation of AAPG from NHSG and POPG felsic endmembers becomes quite ambiguous, but using the syenitic Mardabah Complex sheds some light on the processes involved in generating these endmembers. The fractionation trends in Figure 4.1 are defined by the NHSG (fractionated) granitoids and clearly have affinities with MORB. These fractionate along with the syncollisional suites to finally produce perthitic endmembers similar to the AAPG suites. AAPG samples clearly do not show this trend, but rather a lateral fractionation from the AAPG syenites (~60 wt% SiO2) to the more evolved alkali samples (~75 wt% SiO2). This trend is particularly clear when using FeO and Na2O+K2O vs. SiO2 parameters. These are clearly two different mantle sources, but share the common trait of fractionation to similar alkali endmembers. It becomes apparent that utilising incompatible trace elements is required to separate further these suites and will be discussed shortly.
Trace Element Geochemistry
Although AAPG suites are typically higher in all REE concentrations, this section will focus on the incompatible LILE and LREE that easily distinguish all granitic suites. AAPG suites contain the highest concentrations of Nb (~20-70 ppm), Rb (~150-350 ppm), Ga (~20-35 ppm), Nd (~10-130 ppm) and Y (~30-80 ppm) of any
120 granitoid sampled in the Arabian Shield. The highest values are synonymous with the most evolved samples of the Abanat Suite. As highlighted in Figures 4.2 and 4.3, these AAPG suites are constantly placed at the termination of all data groups, hence appear to be the most evolved. This is most prominent when using the SiO2 vs. incompatible element diagrams as illustrated in Figure 4.2.
Most importantly, AAPG suites are clearly separated from the IA+Syn suites particularly when utilising Rb and Nb. It should be noted that Nb in particular distinguishes the AAPG suites from similar POPG and NHSG (non-fractionated) granitoids. This is also apparent when using Ga, as there is more overlap with the suture granitoids. Although there is some discrimination, there is still significant overlap between the NHSG (fractionated) felsic endmembers and AAPG suites.
LREE such as Nb, Nd and Y are the best incompatible elements for separating similar perthitic granitoids from AAPG suites. As illustrated in Figure 4.3, the most striking feature is the strong fractionation trend exhibited by NHSG (fractionated) samples, IA-Syn suites and to a lesser extent, POPG suites. These clearly originate from the MORB field and fractionate to highly evolved suites with increasing enrichment in incompatible elements. Most importantly, however, these trends are consistently isolated from AAPG suites and show parallel, but never touching, enrichment patterns. By contrast the AAPG suites, including the primitive syenitic endmembers, are clearly not typical MORB like products, but have an enriched source. There is also little fractionation that occurs within the AAPG field, possibly suggesting rapid ascent, but is discussed further in Chapter 7.6.
The use of LREE to discriminate NHSG (fractionated) felsic samples from AAPG suites is to some extent misleading. Incompatible elements such as Nb, Rb and Zr when plotted with silica create the impression of AAPG suites being the end product of intense fractionation similar to NHSG (fractionated) endmembers (Figures 4.2 and 4.3). Although the lateral fractionation from primitive syenitic endmembers supports differentiated magmatic evolution, the use of incompatible element ratios helps reinforce the independent evolution of these AAPG suites. As illustrated in Figure 4.3, AAPG suites contain amongst the lowest Ce/Yb and Y/Nb incompatible LREE ratios of ~5-50 and ~0.5-2 respectively. The highest values correlate with the primitive syenite.
121 Figure 4.5 part1: Average crust normalised REE patterns of whole rock samples >60% SiO2. These are the most felsic endmembers of the granitic units and are thought to represent the final products of fractionation from mafic parents displayed in Figure 4.4. A) Hijaz syncollisional age samples displaying a flat pattern that does not lie within the WPG realm, hence is a product of N-MOB contamination (Chapter 7.2). B) NHSG granitoids show crustal contamination, fractionation (blue) and N-MORB derived patterns (purple). This encroach the WPG realm, but are still geochemically different to AAPG (Chapter 4.2.2). The red line represents NHSG (non-fractionated) samples interpreted to be a change in mantle chemistry (Chapter 7.3). C) Mineralogically similar POPG and AAPG show clear differences in HREE and crustal contamination in the LILE. The two different mantle sources are discussed further in Chapter 7.3. References for the published MORB data fields and sample suite abbreviations are displayed in Chapter 4.2. Average crust normalising values are taken from Wedopohl (1995).
122 Figure 4.5 part2: Average crust normalised HREE patterns of whole rock samples >60% SiO2. These are the most felsic endmembers of the granitic units and are thought to represent the final products of fractionation from mafic parents displayed in Figure 4.4. A) Hijaz syncollisional age samples displaying a flat pattern that does not lie within the WPG realm, hence is a product of N-MOB contamination (Chapter 7.2). B) NHSG granitoids show crustal contamination, fractionation (blue) and N-MORB derived patterns (purple). This encroach the WPG realm, but are still geochemically different to AAPG (Chapter 4.2.2). The red line represents NHSG (non-fractionated) samples interpreted to be a change in mantle chemistry (Chapter 7.3). C) Mineralogically similar POPG and AAPG show clear differences in HREE and crustal contamination in the LILE. The two different mantle sources are discussed further in Chapter 7.3. References for the published MORB data fields and sample suite abbreviations are displayed in Chapter 4.2. Average crust normalising values are taken from Wedopohl (1995).
123 These ratio values are significant because they clearly isolate the AAPG suites from all other granitoids sampled in the Shield. There is no obvious fractionation within the AAPG field, which reflects their strong enriched mantle like chemistry. All other groups have very high ratios and show a strong fractionation trends from N-MORB mafic endmembers through to aegirine-bearing alkali-granite products. This is the first time that AAPG suites have been clearly isolated from all granitic suites, and show no evidence of fractionation unlike the similar aegirine-bearing NHSG and POPG suites.
Due to the similar age and mineralogy characteristics both of the POPG and AAPG suites, these are compared using trace element spider plots (Figures 4.4 and 4.5). As described above, both the POPG and AAPG suites contain primitive syenitic endmembers. These represent the least evolved granitoids and reflect the mantle from which fractionation to more felsic units occurs. Both are similar in major elements, but the POPG endmember is magnesian rich, whilst the AAPG endmember is ferroan rich. The trace element separation of these two mantle sources is illustrated in Figure 4.4. These are plotted against the similar age IA+Syn Rithmah Complex for a reference sample similar to an N-MORB mantle signature.
Both AAPG and POPG syenites exhibit LREE enrichment with a moderate depletion in HREE, most likely attribute to the presence of zircon. Interestingly, AAPG suite contains slightly higher HREE concentrations despite the presence of olivine and large well developed zircon crystals absent in the POPG suites. The key differences between the two sources are illustrated in the incompatible LREE. The AAPG syenite contains no negative Nb, Th or Pb anomalies prominent in the POPG syenite. This is thought to reflect the absence of crustal contamination in AAPG magmatic evolution.
There is enrichment in middle REE (Nd and Zr) and a positive Eu anomaly reflecting the presence of hornblende and olivine in the samples. Most importantly, the AAPG syenite shows no affinities with N-type MORB or crustal contamination. This suggests an enriched mantle source that is clearly differentiated from all other sources (including suture mafics). How these generate is discussed further in Chapter 7.6.
124 All AAPG suites, excluding the syenite, are also plotted against POPG suites to differentiate the evolved nature of the felsic endmembers. Highlighted in Figure 4.5, is an obvious enrichment in HREE displayed by the AAPG suites. This shows no correlation with mineralogy because the POPG suites contain almost identical minerals with the absence of aegirine. This suggests that they are clearly products of an enriched mantle source, possibly OIB like. The AAPG suites show a slight enrichment in middle REE, which most likely correlate with the presence of amphiboles. Similar, to the POPG suites, AAPG suites contain negative Sr, Eu, P, Ti, and Ba anomalies. This is likely attributed to their affinity with plagioclase fractionation/removal from the melt. One important difference is the absence of an Nb anomaly in the AAPG suites. This is also reflected in the syenitic endmember, which suggests that unlike the POPG suites, the AAPG suites contain little if any crustal contamination. The significance of the absence of contamination is discussed further in Chapter 7.5.
4.3 Whole Rock Isotope Geochemistry.
Chapters 2 and 3 summarise the Arabian Shield as discrete western island arc and eastern continental terranes. Conveniently, this provides ample opportunity to isotopically categorise and determine the tectonic significance involved in each of their formations. The Arabian Shield is consistently referred to as the largest exposure of juvenile continental crust on Earth based on lead (Pb), neodymium (Nd), samarium (Sm) and strontium (Sr) parameters (Stein and Goldstein, 1996; Stoeser and Frost, 2006) and now more recently, hafnium (Hf) isotopes (Chapter 3.3). Stoeser and Frost (2006) highlight the absence of wholerock Nd-Sm-Sr-O isotopic analysis in the Shield and characterise terranes with limited data sets. This section aims to utilise Nd, Sm and Sr isotopes to discriminate island-arc, syncollisional, post-tectonic and anorogenic granitic suites, hence tectonic setting, and understand further its respective magmatic evolution in both convergent and extensional environments.
Whole rock Nd, Sm and Sr isotopic analysis is a valuable, but expensive process involving complex chemical and time dependant procedures. As a consequence, it was not feasible to evaluate all 137 samples collected from the Arabian Shield. Alternatively, one sample was chosen from each suite to represent its defining
125 geochemical signature. 21 samples that had previously been petrographically interpreted, age dated and analysed for Hf isotopes (Chapters 2 and 3) are thought to make an adequate representation of the various granitic suites. An additional 10 country rocks and mafic autoliths were also analysed and can all be viewed in Appendix 6. These possible crustal contamination components (structural intrusion relationships) and mafic units (product of mantle) are used to constrain further the magmatic and fractionation processes involved in generating the wide variety of granitoids sampled. Nd-Sm and Sr isotope analyses are summarised in Table 4.1 and Figures 4.6-4.8. Raw data are displayed in Appendix 6 and procedural details are described in Appendix a6.
4.3.1 Island Arc and Syncollisional Granitoids (IA+Syn).
The IA+Syn suites are the oldest plutons (845-693Ma) sampled in the Arabian Shield and consequently contain the most mantle like geochemistry (Chapter 4.2.1). This group includes the Makkah Suite, Shufayyah Complex , Jar-Salajah Complex and the felsic volcanics of the Subh Suite. However, the 600Ma Rithmah Complex is also included in this group because of its similar mantle geochemistry. Unsurprisingly, these suites contain the lowest concentrations of REE (Chapter 4.2.1). These suites are strictly confined to the western side of the Shield, mostly concentrated in the Hijaz terrane. The isotopic values are summarised in Table 4.1 and displayed in Appendix 6.
With the exception of the Al Hafoor Suite mafics (Chapter 4.2.2), the IA+Syn samples contain the lowest Sm and Nd concentrations. These range from 2.05-6.43 ppm and 7.68-28.7 ppm respectively. The lowest values correlate with the Rithmah mafics (rt), whilst the highest are exhibited by the Subh Suite volcanics (sf). The oldest suite (dm) also contains elevated concentrations similar to that of the Subh Suite. The 147Sm/144Nd and 143Nd/144Nd ratios are amongst the highest of any granitoids sampled ranging from 0.1186-0.1615 and 0.512582-0.512790 respectively. Samples with the lowest ratios also contain the most depleted REE concentrations. Sr concentrations are amongst the highest of all granitoids ranging from 207.8-826.3 ppm with the exception of the felsic volcanic (sf) which has 33 ppm. The oldest suite (dm) contains the highest concentration of Sr. IA+Syn suites and also displays the lowest 87Sr/86Sr ratios from 0.704028-0.706177 with the exception of the felsic volcanic (sf) with 0.752144.
126 The ɛNd (t) values of the IA+Syn samples (calculated using Goldstein et al., 1984) are the highest of all suites ranging from 5.67-6.04. Figure 4.6 clearly displays the juvenile nature of these units, which are separated from the remainder of the sampled suites. These are the oldest and most juvenile suites and lie above the younger field consisting of all terranes and sampled granitoids (Figure 4.6). Interestingly, there is only subtle variation in ɛNd despite the large variation in crystallisation age (845- 600Ma). The isolated nature of these granitic products indicates a homogeneous mantle chemistry spaning ~350Ma. This is discussed further in Chapter 7.2. The depleted mantle model ages range from 902-1050Ma, which is consistent with the suggested Pan-African Hf model ages described in Chapter 3.3. The oldest model age belongs to the oldest unit (dm) and youngest age to the youngest unit (js).
With the exception of the 600Ma Rithmah Complex, the calculated 143Nd/144Nd (t) and 87Sr/86Sr (t) ratios for IA+Syn suites are amongst the lowest of all sampled granitoids. The Nd values range from 0.511852-0.512156 with the lowest and highest values corresponding with the Makkah Suite and Rithmah Complex respectively. Sr values range from 0.699021-0.703102 with the highest and lowest values corresponding with the Subh Suite and Makkah Suite respectively. It should be noted that the Subh Suite contains high Rb/Sr ratios and has experienced Sr loss, most likely in an open system (felsic volcanic). This causes unreliable initial Sr (below the initial Earth’s 4.5Ga value) in a similar manner to that of some AAPG suites discussed shortly.
Figure 4.7 utilises the calculated Nd and Sr initial values plotted against Nb and
SiO2 parameters. The oldest (Makkah Suite) and youngest (Rithmah Complex) units contain the lowest (<57 wt%) SiO2 content and are easily separated from the more evolved, intermediate (~65-73 wt%) suites correlating with the Shufayyah and Jar- Salajah Complexes. However, all IA+Syn units contain low (<10ppm) Nb contents and resemble fractionation from N-MORB type mantle (Figure 4.7). This is consistent with the N-MORB type characteristics displayed by these suites in Chapter 4.2.
One of the most important differences to highlight is the change is Nd isotope composition between the oldest Makkah Suite (867Ma) and youngest Rithmah Complex (600Ma). These contain similar geochemical parameters, but the Makkah Suite contains a much lower Nd (t) value. This is apparent in Figure 4.7 in which the Makkah Suite is
127 emplaced in the vicinity of the Khida terrane field alongside the NHSG (fractionated) mafic endmembers. The Rithmah Complex has a much higher value associated with the POPG and AAPG syenitic endmembers. All remaining IA+Syn suites reside below the enriched mantle zone. This trend is also observed in Figure 4.8 which utilises Nd (t) and Fe#. The Makkah Suite, Shufayyah Complex and the Rithmah Complex contain the lowest Fe# (0.49-0.57), whilst the more evolved Jar-Salajah Complex and Subh Suite have higher Fe# (0.72-0.74).
Figure 4.6: Age vs. ɛNd (t) plot for all 20 granitoids and associated mafics and volcanics. Highlighted in red are the economic AAPG samples, whilst in blue and purple are the NHSG (fractionated) samples. The two grey fields are Shield data taken from Stoeser and Frost (2006) and represent the Paleoproterozoic (2400-1660Ma) Khida terrane (bottom) and all Neoproterozoic (<1000Ma) Shield terranes (top). The Abt Formation field is taken from Lewis (2009). Note the association of the mafics and Ad Dawadimi granitoids (ky) with the Khida terrane, whilst all remaining suites have a close affinity with more juvenile terranes. The change in mantle chemistry between NHSG (fractionated) and younger AAPG suites may be explained by contaminated vs. enriched mantle processes, which are discussed further in Chapter 7. ɛNd (t) model ages are calculated based on ratios taken from Goldstein et al. (1984). All raw data are displayed in Appendix 6 and the sample suite abbreviations in Chapter 4.2.
128 Overall, the trends in both Figures 4.7 and 4.8 are suggestive of two mantle source types. The oldest units are associated with a contaminated N-MORB mantle (possibly incorporating the Khida terrane) and fractionate to more evolved endmembers isolated below the isotopic enriched field. The youngest IA+Syn unit is emplaced within the enriched mantle zone consisting of the POPG and AAPG syenitic endmembers. This is also an N-MORB source, but suggests limited crust-mantle interaction. The tectonic implications of this are discussed further in Chapter 7.
4.3.2 Nabitah and Halaban Suture Granitoids (NHSG).
Granitic suites that encompass the NHSG group mark the post-tectonic (<636- >600Ma) stitching of western and eastern parts of the Shield. As a consequence, these suites contain the most complicated magmatic history of all granitoids sampled. The isotope behaviour displayed by these samples incorporates both characteristics of IA- Syn and AAPG suites, hence are the most fascinating. This group is broken into two subgroups as in Chapter 4.2: 1) NHSG (fractionated) which includes the Al Hafoor and Kawr Suite and; 2) NHSG (non-fractionated)) which includes the Ibn Hashbal Suite, Najirah Granite and Wadbah Suite. The isotopic values are summarised in Table 4.1 and displayed in full in Appendix 6.
Mafic/intermediate NHSG (fractionated) samples exhibit some of the lowest Sm and Nd concentrations of any suite sampled. The Al Hafoor Suite (ao) contains values of 1.7-1.8 ppm and 7.7-11.1 ppm, whilst the Kawr Suite (kw) is higher at 5.7- 22.47 ppm and 25.7-100.25 ppm respectively. The 147Sm/144Nd and 143Nd/144Nd ratios are high ranging from 0.0918-0.1384 and 0.512403-0.512530 (ao) through to 0.1350- 0.1356 and 0.512477-0.512628 (kw). NHSG (fractionated) felsic samples display lower than expected Sm-Nd concentrations of 2.66-16.23 ppm (ao) and 3.37-18.83 ppm (kw) respectively. The 147Sm/144Nd and 143Nd/144Nd ratios are also low ranging from 0.512406 (ao), but higher at 0.512592 for the aegirine alkali-granite (kw51p).
NHSG (fractionated) suites contain a large range in Sr concentrations. The mafic units have the highest values of 454.7-1024 ppm (ao) and 97.2-235.3 ppm (kw), but also possess the lowest 87Sr/86Sr ratios ranging from 0.704720-0.704789 (ao) and 0.705530-
129 0.727509 (kw). Conversely, the felsic endmembers correlate with the lowest Sr concentrations and highest 87Sr/86Sr ratios. These are 43.9 ppm and 0.806404 (ao) and 55.2 ppm and 0.760414 (kw) respectively.
Figure 4.7: Top left) Nd (t) vs. Sr (t) wholerock isotopes indicate 2 trends: NHSG (fractionated) mafics contain higher initial Sr values; and younger POPG and AAPG suites contain lower initial Sr values. This suggests the latter having limited crust-mantle interaction. Top Right) Nd (t) vs. Nb indicates two mantle types: N-MORB basalts that fractionate to produce most low Nb Arabian Shield suites; and enriched Red Sea MORB that correlates with high Nb AAPG suites. There is also a slight increase in Nd (t) with the appearance of NHSG (non-fractionated) granitoids, which is thought to resemble slab tear. The differing sources are discussed further in Chapter 7. Bottom) Nd (t) vs. SiO2 highlights the clearly differing NHSG (fractionated) mafics and younger enriched POPG and AAPG sources. The two NHSG (fractionated0 mafics are contaminated N-MORB units (Chapter 4.2) that fractionate to different endmembers. The appearance of younger NHSG (non-fractionated) suites is thought to represent a change the mantle chemistry beneath the belt (slab tear), hence cause differing felsic products. The initial contamination is possibly related to the nearby Khida terrane. The tectonic implications of this are discussed in Chapter 7. All raw data are displayed in Appendix 6 and sample suite abbreviations in Chapter 4.2. Isotopic fields are taken from Stoeser and Frost (2006) and the N- MORB and Red Sea MORB from Ito et al. (1987) and Volker et al. (1993) respectively.
130 NHSG (non-fractionated) suites contain amongst the highest Sm-Nd concentrations ranging from 12.84-16.81ppm and 61.75-126.92 ppm respectively. They also possess high 147Sm/144Nd and 143Nd/144Nd ratios ranging from 0.0791-0.1506 and 0.512417-0.512630 respectively. The lowest values correlate with the oldest suite (ih) and the highest to the younger more evolved Najirah Granite. Felsic units from both NHSG groups correlate remarkably well with the AAPG suites. It is worth mentioning that these NHSG suites are mineralogically and geochemically similar to AAPG suites. NHSG (non-fractionated) samples display the lowest Sr concentrations ranging from 21.9-57.7 ppm. However, they contain the highest 87Sr/86Sr ratios ranging from 0.762602-0.803196. The lowest values are associated with the most evolved suite (wb).
The ɛNd (t) values (calculated using Goldstein et al., 1984) for NHSG (fractionated) mafics are quite low ranging from 2.63-3.95 (ao) and 1.68-4.39 (kw). The felsic endmembers are slightly elevated at 3.42 (ao) and 4.79 (ao). Figure 4.6 highlights the fractionation trend from the mafic endmembers to felsic products. The most interesting observation is the position of the mafic units residing in the Khida terrane field. The fractionated products together with the juvenile POPG and AAPG suites, contain higher ɛNd values and reside in the field composed of all juvenile Shield terranes. The NHSG (fractionated) mafic geochemistry outlined in Chapter 4.2 suggested derivation from a contaminated N-MORB like source. It is suggested that the contamination is from the nearby Paleoproterozoic crust of the Khida terrane, which is discussed further in Chapter 7. Overall, the most important observation is that the NHSG (fractionated) mafic endmembers clearly are less juvenile than younger (600Ma) mafic endmembers, suggestive of a change in mantle source.
NHSG (non-fractionated) ɛNd (t) values range from 3.44-4.99 with the lowest and highest values reflecting the most evolved (nr) and oldest (ih) suites respectively. These overlap the juvenile AAPG realm and appear to resemble a change in mantle chemistry (Figure 4.6). The transition from contaminated mafics to more juvenile felsic products is discussed further in Chapter 7. NHSG (fractionated) DM model ages range from 927-1240Ma (ao) to 888-1288 (kw). The lowest and highest ages values correspond with the felsic and mafic components respectively. NHSG (non- fractionated) DM ages range from 825-1236Ma with the lowest and highest values correlating with the oldest and most evolved suite respectively. Both NHSG group
131 model ages are consistent with the suggested Pan-African Hf model ages described in Chapter 3.3.
The calculated 143Nd/144Nd (t) ratios for NHSG (fractionated) suites are low to high ranging from 0.511935-0.512085. The lowest and highest values correspond with the Kawr Suite, but the Al Hafoor Suite has very similar ranges. Calculated 87Sr/86Sr (t) ratios range from 0.698286-707887 with the lowest and highest values correlating with the Al Hafoor and Kawr Suites respectively. NHSG (non-fractionated) 143Nd/144Nd (t) ratios are higher ranging from 0.512031-0.512097 with the lowest and highest values corresponding with the Najirah Granite and Ibn Hashbal Suite respectively. Calculated 87Sr/86Sr (t) ratios range from 0.687647-753914 with the lowest and highest values correlating with the Wadbah and Ibn Hashbal Suites respectively. It should be mentioned that the Al Hafoor and Wadbah Suites and the Najirah Granite contain high Rb/Sr ratios and have experienced significant Sr loss. This causes unreliable initial Sr values (well below the initial Earth’s 4.5Ga value) which are not utilised in this study. This is most likely due to their highly perthitic nature, which results in open system unmixing, hence loss of Sr.
The most significant trends are illustrated in Figure 4.7 in which initial Nd and
Sr values are plotted with Nb and SiO2 parameters. NHSG (fractionated) mafic units contain low initial Nd and relatively high initial Sr when compared to juvenile AAPG and POPG syenites. This isotopic distinction between mafic endmembers is suggestive of two mantle sources. The NHSG (fractionated) mafics are characterised by N-MORB affinities (Chapter 4.2) and suggest early stage contamination (high initial Sr). This becomes apparent when they are compared with more juvenile AAPG and POPG suites that appear to have had limited crust-mantle interaction. The use of incompatible elements helps to constrain further the notion of two mantle sources (Figure 4.7). NHSG (fractionated) suites contain values of <10ppm, which is suggestive of an N- MORB like composition. However, there appears to be a slight increase in Nd (t) values (10-15ppm) with the appearance of NHSG (non-fractionated) samples and NHSG (fractionated) Kawr Suite felsic endmembers. These are incorporated into the lower spectrum of the enriched mantle field, which is possibly the result of a change in mantle chemistry beneath the Nabitah Belt (Chapter 7).
132 This trend is again reinforced when Nd (t) is compared with SiO2 (Figure 4.7). NHSG (fractionated) mafics are clearly a different mantle source from more juvenile AAPG and POPG syenites. These also appear to be incorporated into the Khida terrane field, which may be a possible contaminant. NHSG (fractionated) mafics show two fractionation trends from a similar source: 1) Al Hafoor Suite mafics produce perthitic endmembers well below the enriched mantle zone constrained by AAPG suites; and 2) Kawr Suite mafics produce aegirine-bearing alkali-granites that reside into the enriched mantle zone and seem to coincide with the appearance of NHSG (non-fractionated) suites. This is suggestive of a change in mantle chemistry beneath the Nabitah Belt after the generation of the NHSG (fractionated) mafic source. This may reflect a tear in the subducting slab, but is discussed further in Chapter 7.
Figure 4.8: 143Nd/144Nd (t) vs. Fe# highlighting the differences in mafic sample mantle source chemistry. Note the similar age NHSG (fractionated) mafics that fractionate to produce perthitic (Al Hafoor) and aegirine-bearing perthitic (Kawr) alkali-granites. These represent similar initial mantle chemistry, but terminate with depleted and enriched mantle derived granitoids respectively. This is suggestive of a change in mantle chemistry, which is possibly related to slab tear processes, but are differentiated from the lithospheric delamination processes of AAPG suites. These tectonic implications are discussed further in Chapter 7. All raw data are displayed in Appendix 6 and sample suite abbreviations in Chapter 4.2.
133 A similar trend is apparent when plotting Nd with Fe# (Figure 4.8). NHSG
(fractionated) suites contain a large range in SiO2 (~50-76 wt%) and Fe# (0.44-0.83). The lowest and highest values correspond with the Al Hafoor Suite, but the Kawr Suite shares similar ranges. NHSG (non-fractionated) suites contain high SiO2 (~71-74 wt%) and Fe# (0.82-0.94) values with lowest and highest values correlating with the Wadbah Suite. As illustrated in Figure 4.8, NHSG (fractionated) mafics show two trends: the Al Hafoor mafics fractionate to less juvenile perthitic alkali-granites; and the Kawr Suite mafics (same source) fractionate towards aegirine-bearing perthitic alkali-granites. Once again, this suggests a change in mantle behaviour after the generation of similar mafics. This possibly correlates with the appearance of NHSG (non-fractionated) ferroan granitoids, which may reflect a change in mantle chemistry beneath the Nabitah Belt.
Overall, the complicated tectonic interplay of western and eastern Shield fragments produces NHSG mantle sources that are distinguished from enriched AAPG sources. These display fractionation trends from crustally contaminated mafic endmembers (possibly Khida terrane) that produce perthitic and aegirine perthitic endmembers. The onset of NHSG (non-fractionated) suites may resemble a change in mantle chemistry related to slab tear process and is discussed further in Chapter 7.
4.3.3 Post-Orogenic Perthitic Granitoids (POPG).
POPG suites are of similar age to AAPG suites (<636->600Ma), but posses stronger geochemical affinities with both NHSG groups (Chapter 4.2.2). POPG suites include the Admar, Al Khushaymiyah, Haml and Idah Suites and the crustally derived garnet-bearing Malik Granite is also included here as it intrudes the Idah Suite. The isotopic values are summarised in Table 4.1 and displayed in full in Appendix 6.
The POPG suites exhibit a somewhat intermediate Sm and Nd concentration ranging from 2.44-6.12 ppm and 15.12-42.42 ppm respectively. The most primitive syenitic endmember (ad) contains the highest values and the oldest suite (ky) displays the lowest values. It is worth noting the most primitive AAPG syenite (mr) has very similar Sm/Nd concentrations to that of the POPG syenite (ad). However, as described below, the isotope ratios produce different results. The 147Sm/144Nd ratios range from
134 0.0873-0.1128, whilst the 143Nd/144Nd ratios range from 0.512340-0.512512. The lowest values are associated with the Admar and Al Khushaymiyah Suites, whilst the highest value belongs to the most geochemically evolved Idah Suite. The crustal Malik Granite has higher Sm-Nd concentrations than that of the Idah Suite into which it intrudes. The values are 6.24 ppm and 29 ppm respectively. Overall, the values are marginally lower than that of the AAPG suites, but significantly lower than both NHSG groups.
POPG granitoids contain a large range in Sr concentration from 24.8-894 ppm. The highest value correlates with the most primitive suite (ad), whilst the lowest is the more evolved (hla) suite. The Malik Granite contains an intermediate value of 102.1 ppm. 87Sr/86Sr ratios range from 0.703945-0.735379 in the POPG suites and 0.7462676 for the Malik Granite. Once again, the highest and lowest ratios belong to the evolved (id) suite and primitive ad suite respectively.
The ɛNd (t) values (calculated using Goldstein et al., 1984) range from 1.81- 4.29, with the lowest and highest values correlating with the primitive syenite (ad) and oldest suite (ky) respectively. At a glance POPG and AAPG suites appear to be similar, but as highlighted in Figure 4.6, show a dissimilar trend. The position of the primitive syenitic Admar Suite encroaches the AAPG field at 4.29, suggesting its juvenile nature. The close association of the Haml and Idah Suites at 3.8 suggests that these are closely geochemically related to the Admar Suite source. As outlined in Chapter 4.2, these suites are synonymous with contamination of an N-MORB like source.
The Al Khushaymiyah Suite, however, is incorporated into the Khida terrane crustal array in a similar manner to that of the NHSG (fractionated) mafics. This Afif suite is less juvenile than the other POPG suites and is possibly contaminated by the nearby Khida terrane in the early stages of fractionation. The depleted mantle model ages range from 865-1054Ma, which is consistent with the suggested Pan-African age Hf model ages described in Chapter 3.3. The lowest model age correlates with the youngest suite (ad), whilst the oldest belongs to the oldest suite (ky). The crustal Malik Granite actually contains the highest age at 1180Ma.
The calculated 143Nd/144Nd (t) ratios for POPG suites are low to intermediate ranging from 0.511957-0.512086. The lowest and highest values correspond with the Al
135 Khushaymiyah and Admar Suites respectively. Calculated 87Sr/86Sr (t) ratios range from 0.654438-703679 with the lowest and highest values correlate with the Idah and Al Khushaymiyah Suites respectively. The Idah Suite also contains high Rb/Sr ratios and has experienced significant Sr loss. This causes unreliable initial Sr values (below the initial Earth’s 4.5Ga value) which are not utilised in this study. This is likely due to its highly perthitic nature, which results in open system unmixing, hence loss of Sr.
The geochemical similarities between POPG and AAPG pose difficulties in distinctive isotope signatures, which is particularly noticeable in Figure 4.7.Both POPG and AAPG syenites share an isotopically similar mantle source suggestive of limited crust-mantle interaction and most importantly, this is distinguished from similar age NHSG (fractionated) mafics. However, Figure 4.7 highlights the importance of incompatible elements such as Nb to distinguish groups. POPG suites contain Nb concentrations <15 ppm, which are clearly lower than AAPG suites. More importantly, there is an affinity for POPG suites for the N-MORB field rather than the enriched field in which AAPG suites lie. This is consistent with the geochemistry described in Chapter 4.2. The difference in mantle sources is discussed further in Chapter 7.2.
Another important factor illustrated in Figure 4.7 is the difference in fractionation trends exhibited by POPG and AAPG suites when utilising Nd (t) and
SiO2 parameters. Both primitive syenites contain a similar source, but POPG syenites fractionate towards perthitic endmembers below the enriched mantle zone constrained by AAPG suites. This suggests a juvenility decrease, which may reflect the contamination of the N-MORB source (Chapter 4.2). Another interesting aspect is that the Al Khushaymiyah Suite is separated into the Khida terrane field and has an obvious differing mantle source to other POPG units. All these trends are repeated in Figure 4.8, which utilises Nd (t) and Fe#. POPG suites range from 0.59 to 0.87 with the lowest and highest values corresponding with the Al Khushaymiyah and Idah Suites respectively.
Overall, despite similar age and geochemical parameters, POPG suites are distinguished from AAPG suites. They display fractionation trends from a similar source, but diverge into less juvenile endmembers. POPG suites also contain multiple sources with the Al Khushaymiyah showing an affinity with the Khida terrane (possible contaminant). The differing mantle chemistry is discussed further in Chapter 7.2.
136 4.3.4 Anorogenic Aegirine Perthitic Granitoids (AAPG).
The AAPG suites are defined not only by their anorogenic age (<600Ma), but their distinct geochemistry (Chapter 4.2.4). This group includes the Abanat Suite, Al Bad Granite Super Suite, Al Hawiyah Suite, Ar Ruwaydah Suite and the Mardabah Complex. Aside from containing the youngest crystallisation ages, these suites contain the highest concentrations of REE (Chapter 4.2.4). The isotopic values are summarised in Table 4.1 and displayed in full in Appendix 6.
AAPG suites contain Sm and Nd concentrations ranging from 2.68-21.11 ppm and 14.05-138.61 ppm respectively. Coincidently, the most economic suite (aa) contains the highest values, whilst the oldest suite (ku) exhibits the lowest values. The 147Sm/144Nd ratios range from 0.0921-0.1317, whilst the 143Nd/144Nd ratios range from 0.512446-0.512639. Interestingly, samples (aa) and (ku) have the highest REE geochemistry, but display the lowest Nd/Sm ratios. The concentration and ratios values of AAPG suites are elevated above older IA+Syn and crustal granitoids. More importantly, these are elevated from the similar age POPG suites and are also lower than the NHSG (fractionated) samples.
Economic AAPPG suites (aa, abg) contain the lowest Sr concentrations of 9.9 and 9.3 ppm respectively. This is coupled with the highest 87Sr/86Sr values of 0.990950 and 1.089832 which are clearly outliers. This is likely due to its highly perthitic nature, which results in open system unmixing, hence loss of Sr. The remainder of the AAPG suites range from 180.9-570.6 ppm and 0.704534-0.729219. It also worth mentioning the highest Sr concentration and lowest ratio belongs to the 525Ma olivine syenite (mr).
The ɛNd (t) values (calculated using Goldstein et al., 1984) are amongst the highest, ranging from 2.64-4.99 and as illustrated in Figure 4.6 are tightly confined to the left side of diagram. This highlights the juvenile nature of the youngest suites, which are clearly separated from all other granitoids. The exception to this rule is the Ar Ruwaydah Suite with the lowest value of 2.64, which encroaches the Khida terrane zone. As discussed in Chapter 7.2, this intrudes a POPG suite (nr) and may have incorporated more crustal components than other APPG suites.
137 It is worth noting the position of the most primitive syenitic endmember of the Mardabah Complex (Figure 4.6). This olivine-bearing AAPG represents the mafic endmember from which lateral style fractionation to felsic alkali AAPG occurs. This clearly lies above all other mafic endmembers, particularly the NHSG (fractionated) suites, which produce similar felsic products. This highlights the more juvenile nature of the AAPG samples, suggesting a separate mantle source. The DM model ages range from 851-1079Ma, which are consistent with the suggested Pan-African age Hf model ages described in Chapter 3.3. Once again the most economic suite (aa) contains the youngest model age whilst the oldest suite (ku) exhibits the oldest model age.
With the exception of the Ar Ruwaydah Suite, the calculated 143Nd/144Nd (t) ratios for AAPG suites are amongst the highest of all sampled granitoids. These range from 0.511984-0.512141 with the lowest and highest values corresponding with the Ar Ruwaydah Suite and Mardabah Complex respectively. Calculated 87Sr/86Sr (t) ratios range from 0.619404-702783 with the lowest and highest values correlating with the Abanat and Ar Ruwaydah Suites respectively. It should be mentioned that the most economic (Abanat and Al Bad) suites contain very high Rb/Sr ratios and have experienced significant Sr loss. This causes unreliable initial Sr values (well below the initial Earth’s 4.5Ga value) which are not utilised in this study. This is most likely due to their highly perthitic nature, which results in open system unmixing, hence loss of Sr.
The most significant trends are illustrated in Figure 4.7 in which initial Nd and
Sr values are plotted with Nb and SiO2 parameters. AAPG suites are amongst the most juvenile of all granitoids sampled in the Arabian Shield. Low initial Sr values indicate limited-crust mantle interaction that clearly isolates these juvenile suites. Most importantly, the AAPG syenitic endmembers are much higher in Nd and lower in Sr to that of similar age NHSG (fractionated) mafics. These both fractionate towards similar felsic products, but clearly indicate separate mantle sources. Mantle source discrimination is achieved comparing initial Nd with Nb (Figure 4.7). AAPG suites are clearly enriched from all other granitic suites containing elevated Nb (~20-70 ppm) values. This is suggestive of lithospheric type processes involving enriched mantle, which possibly had a similar geochemistry to present day Red Sea MORB. Only the NHSG (fractionated) aegirine endmembers nudge into this enriched mantle field, but are possibly the result of fractionation and slab tear processes (Chapter 7).
138 Figure 4.7 also uses Nd vs. SiO2 to highlight differing mantle sources between
AAPG and NHSG suites. AAPG syenitic endmembers contain ~60 wt% SiO2, which are of similar levels to that of NHSG (fractionated) mafics, but contain a much higher initial Nd ratio. NHSG (fractionated) mafics contain a lower ratio in the vicinity of the Khida terrane, but both suites fractionate towards similar ~75 wt% SiO2 aegirine-bearing products. Most importantly, these indicate two distinct mantle sources that are discussed further in Chapter 7. These trends are continued when plotting Nd with Fe# (Figure 4.8). AAPG suites contain amongst the highest Fe# (0.72-0.92) of any suites. These are tightly constrained and form the enriched mantle zone and most importantly, are notably dissimilar to the NHSG (fractionated) mafic source. The overlapping of the NHSG (fractionated) granitoids into this enriched zone is discussed further in Chapter 7.
Overall, the trends in Figures 4.6, 4.7 and 4.8 are suggestive of a distinct enriched mantle source. The juvenile nature and low Sr values are indicative of limited crust-mantle interaction that is clearly differentiated from NHSG (fractionated) suites that produce similar felsic products and suggestive of two distinct mantle sources. The tectonic implications are discussed further in Chapter 7.
4.3.5 Shield Volcanics.
The volcanic suites sampled in the Shield display a range of ages from 526- 840Ma and, as expected, convey a wide range in geochemical characteristics. This group includes the Al Ays Group (ay), Mardabah Complex Granophyric dyke (cv), Hadn Formation (hn), Bani Ghayy Group (MCR), Murdama Group (mu), Siham Group (si), and the At Ta’if Group (tfv). These are not defined as felsic endmembers, but exhibit a range in compositions from andesite to rhyolite and also metamorphic schist (Chapter 2). This group is sampled from all regions spread across the Shield with some (hn, MCR and mu) in the form of post-amalgamation basins. The isotopic values are summarised in Table 4.1 and displayed in full in Appendix 6.
Mafic volcanics and metamorphic schist units contain the lowest Sm-Nd concentrations ranging from 2.3-3.1 ppm and 11.9-13.2 ppm respectively.
139 Unsurprisingly, these have the highest 147Sm/144Nd and 143Nd/144Nd ratios of 0.1151- 0.1474 and 0.512412-0.512724 respectively. The most mafic units (ay, MCR) correlate with the highest ratios. Conversely, the felsic volcanics contain elevated Sm-Nd concentrations ranging from 5.5-12.9 ppm and 27.8-67.8 ppm. The lowest and highest values correspond with the least evolved (hn) and most evolved (CV) units. The 147Sm/144Nd and 143Nd/144Nd ratios range from 0.1026-0.1194 and 0.512412-0.512610 respectively. The least evolved unit (hn) donates the highest values.
Sr concentrations also exhibit a large range in concentrations from 22.3-567.2 ppm in the mafic units through to 70.5-885.9 ppm in the felsic units. The lowest and highest values correlate with oldest units (tfv, si) and younger post-collisional basins respectively (MCR, mu). The 87Sr/86Sr ratios range from 0.703967-0.715381 and 0.704383-0.772496 in the mafic and felsic units respectively. Once again the lowest and highest values correlate with the least evolved and oldest units respectively.
The ɛNd (t) values (calculated using Goldstein et al., 1984) range from 2.33-6.08 in the mafic units and 0.70-5.37 in the felsic endmembers. The most mafic unit (ay) correlates with the highest values, whilst the lowest belongs to the volcanic arc (si). Although there is an obvious distribution between mafic and felsic units, Figure 4.6 highlights the distinction between the two. The oldest mafic endmembers appear to be included in, or in close vicinity of, the juvenile mantle field. The pre-collisional basin is understandably an obvious outlier, possessing a crustal like signature. The younger post-collisional basin suites and felsic volcanics clearly lie within the fractionated or juvenile AAPG field. This highlights the possible interplay between country units and intruding plutons. However, this is discussed further in Chapter 7. The depleted mantle model ages range from 698-1131Ma in the mafic units and 865-1276Ma in the felsic units. The lowest value is displayed by the most mafic suite (ay) and the highest by the most crustal like pre-collisional basin (si). This is generally consistent with the suggested Pan-African age Hf model ages described in Chapter 3.3.
As expected, volcanic units span a large range in isotopic signatures, but also reflect granitic sources in which they are associated e.g. Mardabah dykes. For this reason, volcanics are not a distinguished package of rocks. Calculated 143Nd/144Nd (t) values range from 0.511706-0.512142 with the lowest and highest values corresponding
140 with the Siham Group (750Ma) and Hadn Formation (598Ma) respectively. There is a general trend for the oldest basins to contain much lower initial Nd ratios. Calculated 87Sr/86Sr (t) ratios range from 0.702814-707962 with the lowest and highest values correlating with the Hadn Formation and Siham Group respectively. A similar trend to that of Nd occurs with Sr, but this time the oldest basins have the highest Sr values.
Figure 4.7 illustrates, with the exception of two outliers, volcanic units are confined to the within the N-MORB mantle realm. This is particularly evident when Nd (t) is compared with Nb whereby the majority of volcanics contain <10 ppm. The granophyric dyke contains 80 ppm, but is affiliated with the Mardabah Complex, so understandably it plots near the enriched mantle zone. The other outlier is a pre- collisional basin that possesses a low Nd ratio with a Nb level of 10ppm and plots beneath the N-MORB mantle zone.
Volcanic units also display some interesting trends with SiO2 as a parameter (Figure 4.7). The oldest units (tfv, si, ay, mu, and bi) contain the lowest Nd (t) values and appear to mingle in the Khida terrane field area. This possibly suggests that these are potential contamination components of Nabitah Suture mafic endmembers in the same vicinity. The youngest post-orogenic basin (hn) is affiliated with juvenile and enriched POPG and AAPG endmembers, which also could be incorporated at a late stage in A-type formation. This trend continues when utilising initial Nd and Fe# (Figure 4.8). With the exception of the felsic Siham group (0.82) and Mardabah rhyolitic dyke (0.79), Fe# are low ranging from 0.28 (tfv) to 0.49 (ay and mu). Volcanic units show similar trends to those of SiO2 values, suggesting older (N-MORB type) and younger (enriched) possible crustal contaminants.
Overall, volcanics display isotopic signatures that resemble two granitic sources and appear to be consistent with the boundaries of differing depleted and enriched mantle chemistry. The interaction between contamination and fractionation of granitic parents is discussed further in Chapter 7.2.
141 4.3.6 Isotope Geochemistry Summary
Table 4.1: A summary of neodymium (Nd), samarium (Sm) and strontium (Sr) isotopes determined by TIMS of all 20 magmatic suites (top) and associated mafics+volcanics (bottom). All raw data and details of this procedure are illustrated in Appendix 6 and Appendix a6 respectively. Calculated model ages are based on ratios taken from Goldstein et al. (1984). The weighted average age is directly dated in Chapter 3.2 with the exception of * values which were taken from Johnson (2006).
147 144 143 144 143 144 87 86 87 86 Sample Terrane Age (Ma) Sm (ppm) Nd (ppm) Sm/ Nd Nd/ Nd Nd/ Nd (t) 2σ ɛNd ɛNd(t) DM(t) Rb (ppm) Sr (ppm) Sr/ Sr 2σ Sr/ Sr (t) Abanat Suite [aa166] Ha'il 585* 21.11 138.61 0.0921 0.512466 0.512113 8.3 -3.35 4.47 851 148 9.9 0.990950 14.2 0.619404 Admar Suite [ad194] Hijaz 599.2 6.12 42.42 0.0873 0.512428 0.512086 11.1 -4.09 4.29 865 41 894.3 0.703946 12 0.702819 Al Bad Suite [abg179] Midyan 597.4 5.60 25.74 0.1317 0.512639 0.512123 8.1 0.02 4.99 940 159 9.3 1.089832 15.1 0.652145 Al Hafoor Suite [ao85] Tathlith 636 2.66 16.23 0.0991 0.512406 0.511993 13.3 -4.51 3.42 982 179 43.9 0.806404 12.8 0.698286 Al Hawiyah Suite [hwg07] Asir 591.9 8.35 47.65 0.1060 0.512520 0.512109 8.3 -2.31 4.55 886 200 180.9 0.729219 10.8 0.702226 Al Khuashaymiyah Suite [ky129] Afif 601.2 2.44 15.12 0.0974 0.512340 0.511957 7.7 -5.81 1.81 1054 107 672.8 0.707630 10.5 0.703679 Ar Ruwaydah Suite [ku139] Ad Dawadimi 612.1 2.68 14.05 0.1153 0.512446 0.511984 7.5 -3.74 2.64 1079 88 295.9 0.710556 11.6 0.702783 Haml Suite [hla110] Afif 608.6 3.86 21.52 0.1086 0.512478 0.512045 7.1 -3.13 3.73 967 125 248.0 0.715626 12 0.702543 Ibn Hashbal Suite [ih68] Asir 617.6 16.61 126.92 0.0791 0.512417 0.512097 9.3 -4.30 4.99 825 61 32.9 0.803196 12.4 0.753914 Idah Suite [id159] Ha'il 607.9 4.74 24.75 0.1158 0.512512 0.512051 8.0 -2.46 3.83 985 136 43.9 0.735379 11.8 0.654438 Jar-Salajrah Complex [js202] Hijaz 693.2 3.20 16.33 0.1186 0.512582 0.512043 7.5 -1.10 5.84 902 26 207.8 0.706122 11.6 0.702826 Kawr Suite [kw42] Asir 611.7 22.47 100.25 0.1356 0.512628 0.512085 8.0 -0.39 4.39 1027 97 97.2 0.727509 13.2 0.701513 Kawr Suite [kw51p] Asir 608 3.37 18.83 0.1084 0.512532 0.512100 6.7 -2.08 4.79 888 110 55.2 0.760414 127 0.707887 Makkah Suite [dm01a] Jiddah 845.6 5.45 24.68 0.1336 0.512592 0.511852 11.2 -0.90 5.94 1050 40 826.3 0.704364 10.2 0.703102 Malik Granite [kg150] Ad Dawadimi 599.6 6.24 29.01 0.1301 0.512495 0.511984 9.8 -2.78 2.33 1180 165 102.1 0.742676 12.6 0.700113 Mardabah Complex [mr191] Hijaz 525.6 7.58 40.64 0.1128 0.512529 0.512141 9.2 -2.13 3.51 930 41 570.6 0.704534 9.5 0.702662 Najirah Granite [nr120] Ad Dawadimi 607 15.38 61.75 0.1506 0.512630 0.512031 9.0 -0.14 3.44 1236 182 57.7 0.779715 19.4 0.696248 Rithmah Complex [rt185] Hijaz 600* 2.05 7.68 0.1615 0.512790 0.512156 7.9 2.97 5.67 1033 16 337.5 0.704028 10.3 0.702784 Shufayyah Complex [su216] Hijaz 715.4 3.81 17.05 0.1353 0.512653 0.512019 7.6 0.29 5.91 956 43 350.8 0.706177 10.4 0.703013 Subh Suite [sf209] Hijaz 698.7 6.43 28.79 0.1351 0.512665 0.512047 9.5 0.53 6.04 930 67 33.0 0.752144 11.1 0.699021 Wadbah Suite [wb65] Asir 615.9 12.84 81.59 0.0952 0.512479 0.512094 8.1 -3.11 4.88 858 63 21.9 0.762602 10.7 0.687647
Al Hafoor Suite [ao88] Tathlith 636 1.8 7.7 0.1384 .512530 0.511953 7.9 -2.11 2.63 1240 16 454.7 0.704720 12.6 0.703831 Al Ays Group [ay187] Hijaz 700* 2.9 11.9 0.1474 .512724 0.512047 8.1 1.67 6.08 698 13 235.9 0.704543 11.2 0.703119 Mardabah Complex [CV192] Hijaz 526 12.9 67.8 0.1154 .512537 0.512140 9.7 -1.97 3.49 942 29 506.1 0.704383 10.8 0.703145 Hadn Formation [hn160] Ha'il 598* 5.5 27.8 0.1194 .512610 0.512142 8.0 -0.55 5.37 865 65 264.5 0.708841 15.5 0.702814 Kawr Suite [kw43] Asir 612 5.7 25.7 0.1350 .512477 0.511935 8.0 -3.14 1.68 1288 0.8 235.3 0.705530 10.6 0.705447 Bani Ghayy Group [MCR105] Afif 630* 3.1 13.2 0.1420 .512630 0.512044 8.1 -0.14 4.27 1090 21 567.2 0.703967 11.9 0.703062 Al Hafoor Suite [MD95] Tathlith 636 1.7 11.1 0.0918 .512403 0.512020 7.8 -4.57 3.95 927 69 1024 0.704789 10.6 0.703144 Murdama Group [mu132] Ha'il 630* 6.2 32.3 0.1154 .512421 0.511945 7.9 -4.22 2.33 1119 60 885.9 0.705698 12.7 0.704010 Siham Group [si116] Afif 750* 9.6 56.8 0.1026 .512211 0.511706 7.7 -8.32 0.70 1276 185 70.5 0.772496 15.5 0.707962 At Ta'if Group [tfv02] Jiddah 840* 2.3 12.1 0.1151 .512412 0.511778 7.8 -4.42 4.36 1131 11 22.3 0.715381 25.6 0.703585
142 4.4 Arabian Shield Granitoid Classification/Tectonic Discrimination.
This section contains tectonic and granite classification schemes that are widely accepted for discriminating global granitic databases. These include: I-S and A plots (Whalen et al., 1987), ferroan/magnesian plots (Frost et al., 2001) and WPG/VAG plots (Pearce et al., 1984a). The aim here is to distinguish the Arabian Shield suites, particularly focusing on the aegirine-bearing endmembers, and to highlight the potential for multiple sources and tectonic process when using such classification schemes.
4.4.1 Post-Orogenic Perthitic Granitoids (POPG) and Anorogenic Aegirine Perthitic Granitoids (AAPG).
As outlined in Chapter 4.2, Arabian granitoids have been separated into POPG (<636->600Ma) and AAPG (<600Ma) groups based on geochronological age and perthitic mineralogy. POPG suites include the Admar, Haml, Idah and Al Khushaymiyah Suites and the Malik Granite (intrudes Idah Suite), whilst AAPG suites include the Abanat, Al Bad, Al Hawiyah and Ar Ruwaydah Suites and the Mardabah Complex. However, as presented in Chapter 4.2, although these groups share similar major element geochemistry, the trace element and isotopic signatures are quite distinctive. It has been outlined in previous sections that POPG suites are derived from a contaminated (possibly Khida terrane) N-MORB source, whilst AAPG are strictly derived from a more enriched, juvenile source with limited crustal interaction. It becomes obvious that POPG and AAPG suites are derived from differentiated sources, but produce similar felsic endmembers. As a consequence, it is felt necessary to compare and contrast these granitoids to help discriminate further their tectonic setting and shed light on their petrogenetic process in the Shield.
A combination of major (Na, K, Ca, Al) and incompatible trace elements (Nb, Y, Zr, Ce and Ga) are widely utilised to discriminate I-A type granitoids. As illustrated in Figure 4.9, all POPG and AAPG samples are plotted using the Whalen et al. (1987) scheme. AAPG have elevated concentrations of Zr (~100-800 ppm), Nb (~30-70 ppm), Ce (~40-270 ppm), Y (~30-200 ppm) and Zn (~40-130 ppm). Major elements
143 Figure 4.9: A-type granite classification scheme modified from Whalen et al. (1987). Highlighted in red are AAPG suites isolated from plate boundaries that contain aegirine-bearing alkali-granites and have a tendency for an A-type classification. Highlighted in orange are similar POPG suites (excluding Na-rich amphiboles/pyroxenes), but are situated in close proximity to suture zones. POPG samples display a similar overlapping pattern straddling both I and A type fields, but are derived from different sources (Chapter 4.2.3). Yellow POPG units correspond with the garnet bearing leucogranite (kg). The significance of the different field trends is discussed further in Chapter 7. References for the published Arabian-Nubian Shield WPG data field and sample suite abbreviations are displayed in Chapter 4.2. All geochemical data are displayed in Appendix 5.
144 such as FeO, CaO, Na2O and K2O are also high and display data points that slightly overlap the I-S zone, but extend far into the A-type zone (Figure 4.9). This overlap is most pronounced when using FeOt/MgO and Na2O+K2O/CaO vs. Zr+Nb+Ce+Y parameters. It is also worth highlighting that this overlap is confined to the Fractionated Granitoid (FG) field in the I-S zone and is attributed to the AAPG primitive syenitic endmember (Mardabah Complex). This is thought to represent the mantle like endmember from which fractionation occurs (Chapter 4.2.4).
POPG suites display lower concentrations of Zr (~230-860 ppm), Nb (~4-7 ppm), Ce (~35-95 ppm), Y (~9-17 ppm) and Zn (~29-48 ppm). This field resides in the upper corner of the I-S zone, frequently overlapping with the AAPG suites into the A- type zone (Figure 4.9). With the exception of the extreme endmembers, POPG suite major elements are virtually identical to that of the AAPG suites. This results in similar field overlapping patterns, thus producing an unsatisfactory discrimination between the two groups. The garnet-bearing POPG is distinguished from the other POPG and AAPG suites as S-type granite, but contains some overlap with less evolved POPG/AAPG samples. The S-type POPG contains low Zr (~75 ppm), Nb (~5 ppm), Ce (~22 ppm) Y (~20 ppm) and Zn (~10 ppm) values, which place them into the I-S field. This is consistent with low FeO, CaO, MgO values, but elevated Na2O and K2O (expected in crustal derived granite) cause some minor overlap into the A-type realm (Figure 4.9).
Another widely accepted classification is that of Frost et al. (2001), which harbours the use of FeO, MgO and SiO2 to suggest ferroan or magnesian suites. As illustrated in Figure 4.10, the AAPG suites are indeed ferroan in nature with the most felsic endmembers at ~0.8. The most primitive AAPG (olivine syenite) correlates with ~0.7, which resides on the border between ferroan/magnesian. It should be highlighted that an AAPG suite (abg) is clearly a mixture of magnesian (~0.4) and ferroan (~0.8) endmembers all containing similar SiO2 content. This trend is also displayed by the crustal granite (kg) ranging from ~0.6-0.8. POPG suites are predominantly magnesian and display a somewhat stable linear trend at ~0.6 with increasing silica content. However, the most felsic endmembers are clearly ferroan at ~0.8.
The majority of both the POPG and AAPG are alkali-calcic in nature, which is a common occurrence for A-type granitoids (Figure 4.10). Interestingly, the most
145 primitive AAPG and POPG syenites are strongly alkalic and show a lateral fractionation pattern towards the felsic alkali-calcic endmembers. The crustal granite also resides in the alkali-calcic field similar to the POPG suite (id) to which it intrudes. The classification of granitoids into metaluminous, peraluminous or peralkaline suites is also illustrated in Figure 4.10. The most primitive AAPG and POPG samples are clearly metaluminous samples, whilst the more felsic units are predominantly peraluminous. The most evolved economic AAPG suite (aa) is an aegirine-bearing peralkaline suite. The pattern displayed by the AAPG/POPG suites appears to fractionate from metaluminous through peraluminous and finally peralkaline endmembers. Unsurprisingly, the crustal granite (kg) is peraluminous like the POPG Idah Suite.
Figure 4.10: A-type granite classification scheme modified from Frost et al. (2001). Following on from Figure 4.9, both red AAPG and orange POPG suites are mineralogically similar and classified as A-types. The yellow samples are POPG S-type melts. A) Both AAPG and POPG display an overlapping pattern intruding both the magnesian and ferroan fields. Note that the AAPG (abg) is both magnesian and ferroan with constant ~75% silica content. B) These suites are predominantly alkali-calcic in nature aside from the alkalic AAPG and POPG syenites (far left). C) The majority of the POPG suites are peraluminous, whilst the AAPG are metaluminous-peraluminous and peralkaline. As discussed in Chapter 7, POPG and AAPG suites are classified as both magnesian and ferroan A-types, but suggest different tectonic processes involved in generating similar products. References for the published Arabian-Nubian Shield WPG data field and sample suite abbreviations are displayed in Chapter 4.2. All geochemical data are displayed in Appendix 5.
146 Tectonic granite discrimination (Pearce et al., 1984a) is also a widely utilised classification scheme. This discounts major element data which are heavily influenced by alteration and commonly unable to distinguish felsic perthitic endmembers. Alternatively, incompatible, alteration independent elements such as Nb, Y, Rb and Ta are employed to distinguish VAG-Syn-Col/ORO/WPG suites. As illustrated in Figure 4.11, for the first time there is a convincing separation between AAPG and POPG suites. AAPG contain the highest concentrations of trace elements that range from Rb=~40-235 ppm, Y=~30-215 ppm and Nb=~35-70 ppm. These suites are clearly confined to the within plate field with no overlap into any other field. POPG suites have lower concentrations ranging from Rb=~40-125 ppm, Y=~10-20 ppm and Nb=~5-8 ppm. These suites are also confined to the VAG field with no overlap. The crustal granite (kg) has values that reflect VAG characteristics with values of Rb=~120 ppm, Y=~20 ppm and Nb=~7 ppm. This is not surprising as this intrudes the POPG Idah Suite. Overall, this reinforces the possibility of multiple tectonic processes involved in generating similar A-type suites in the Arabian Shield.
Figure 4.11: A granite tectonic classification diagram modified from Pearce et al. (1984a). Highlighted in red are the AAPG suites isolated from plate boundaries, whilst the orange are POPG suites that are in juxtaposed to suture zones. As indicated by Figure 4.9, these are both classified as A-types, but this illustrates that they are clearly separated into VAG and WPG fields. The red AAPG are aegirine-bearing and economic whilst the POPG are perthitic and non-economic. It is suggested that these form from two different magmatic processes and is discussed further in Chapter 7. References for the published Arabian-Nubian Shield data fields are displayed in Chapter 4.2.
Overall, A-type discrimination schemes are not suitable for separating Arabian Shield granitoids with similar age and geochemical parameters. I-S and A diagrams and
147 ferroan/magnesian schemes provide a good starting point, but exhibit too much overlap between granitic suites. The differences between A-type suites formed in isolation from plate boundaries (AAPG) to those affiliated with suture zones (POPG) are not easily discriminated with major elements alone. Selected incompatible elements appear to identify the key differences and separate AAPG and POPG into WPG and VAG components respectively. The implications of this are discussed in Chapter 7.
4.4.2 Island Arc and Syncollisional Granitoids (IA+Syn) and Nabitah and Halaban Suture Granitoids (NHSG).
Arabian suites have been separated into IA+Syn (900->636Ma) and NHSG (<636->600Ma) categories based on geochronological age and mafic/fractionated mineralogy (Chapter 4.2). IA+Syn suites directly intrude and cross-cut sutures in the western shield include the Makkah Suite, Shufayyah and Jar Salajah Complexes, Subh Suite and the 600Ma Rithmah Complex. It was established in previous sections that these all share similar geochemical properties and suggest derivation from a contaminated N-MORB source. NHSG suites are younger, intrude major sutures that segment the shield and geochemically reflect contaminated N-MORB sources, but produce two different perthitic endmembers. These suites are subdivided further into: 1) older NHSG (fractionated) suites that show extensive fractionation from mafic to perthitic endmembers (Al Hafoor and Kawr Suites); and 2) younger NHSG (non- fractionated) suites that contain no mafic cumulates (Ibn Hashbal and Wadbah Suites and the Najirah Granite). Both IA+Syn and NHSG groups share similar N-MORB mantle sources, but in the case of the NHSG suites, produce perthitic and aegirine perthitic granitoids similar to POPG and AAPG. As a consequence, it is felt necessary to compare and contrast these granitoids to help discriminate further their tectonic setting and shed light on their petrogenetic process in the Shield.
IA+Syn and NHSG granitoids were discriminated as I and A types using the Whalen et al. (1987) scheme. Figure 4.12 shows that there is a clear separation between older IA+Syn suites and NHSG groups, but exhibits obvious trends worth highlighting. IA+Syn suites display some of the lowest concentrations of Zr (~50-300 ppm), Nb (~2- 10 ppm), Ce (~10-50 ppm), Y (~10-50 ppm) and Zn (~20-100 ppm). These suites are
148 Figure 4.12: A-type granite classification scheme modified from Whalen et al. (1987). Highlighted in blue and black are NHSG (fractionated) and NHSG (non-fractionated samples respectively, whilst the green older IA+Syn suites from the western part of the Shield. It is clear NHSG (fractionated) perthitic and aegirine perthitic samples show overlap between I-type and A-type fields, whilst the younger NHSG (non-fractionated) samples are mostly confined to the A-type realm. Blue NHSG (fractionated) mafics are also plotted, but project below 60% SiO2, hence are included to highlight the fractionation trend only. However, NHSG (fractionated) granitoids extend into both I and A-type fields. The significance of the different field trends is discussed further in Chapter 7. References for the published Arabian-Nubian Shield WPG data field and sample suite abbreviations are displayed in Chapter 4.2. All geochemical data are displayed in Appendix 5.
149 consistently confined to the I-type zone independent of the incompatible element used for discrimination. There is also no overlap into the adjacent A-type realm and as expected, the IA=Syn low silica granitoids contain the highest FeO, MgO, CaO of any suites and thus contain low major element ratio values. Conversely, trace elements are relatively low and confine IA+Syn samples to the I-type realm. With the exception of the microgranite/volcanic Subh Suite, all samples are confined to the unfractionated
(OGT, Whalen et al. 1987) zone within the I-type field (Figure 4.12). The Na2O and
K2O values are high for IA+Syn low silica granitoids, but are still confined to the I-type field and easily distinguished from NHSG suites.
NHSG (fractionated) suites contain both mafic and felsic endmembers and consequently the lowest and highest concentrations of Zr (~50-1000 ppm), Nb (~1-50 ppm), Ce (~2-200 ppm), Y (~2-100 ppm) and Zn (~10-100 ppm). As expected from this large variation, Figure 4.12 displays samples that spread from the I-S field far into the A-type realm. This fractionation trend is consistent across all element plots. It is acknowledged that mafics (<60% SiO2) are plotted and cannot be counted towards any granitic classification trends, but it was felt necessary to highlight the fractionation trend that clearly exists within the same suite. Unsurprisingly, this trend continues when using the major elements FeO, MgO, CaO, Na2O and K2O to discriminate them. The NHSG (fractionated) suites contain mafic and intermediate endmembers that pass through both the FG and OGT zones (Whalen et al., 1987) within the I-type realm (Figure 4.12). The most fractionated perthitic granitoids, some aegirine-bearing, are clearly within the A- type realm. However, using this scheme, they are not distinguishable with POPG and AAPG suites described in the previous section. These clearly resemble different origins and highlight the need for further geochemical separation between the two A-type endmembers (Chapter 4.4.4).
NHSG (non-fractionated) suites correlate with some of the highest concentrations of Zr (~200-1000 ppm), Nb (~20 ppm), Ce (~50-200 ppm), Y (~10-100 ppm) and Zn (~50-100 ppm) observed in the Nabitah Belt. These are exclusively confined within the A-type realm, but occasionally straddle the border (Nb, Ce and Y) of the I-type field (Figure 4.12). Like POPG suites, these perthitic granitoids are high in
Na2O/K2O, but low in FeO, MgO and CaO, thus confined to the A-type realm. The two low silica endmembers (ih) inherently nudge into the OGT zone of the I-type field.
150 Although these samples are clearly A-type granites they cannot be distinguished with AAPG and POPG using this scheme. This highlights the need for further geochemical distinction between the two A-type endmembers (Chapter 4.4.4).
Figure 4.13: A-type granite classification scheme modified from Frost et al. (2001). Highlighted in blue and black are NHSG (fractionated) and NHSG (non-fractionated samples respectively, whilst the green older IA+Syn suites from the western part of the Shield. A) The NHSG (fractionated) suites clearly show magnesian endmembers that fractionate in a similar fashion to IA+Syn granitoids, but finally produce ferroan aegirine-bearing felsic endmembers. There is an onset of ferroan black NHSG (non-fractionated) suites possibly associated with a change in the upwelling mantle chemistry possibly related to slab roll back processes (Chapter 7.2). B) The IA+Syn suites show a calcic/calc-alkalic trend that is mimicked by NHSG (fractionated) samples, but NSHG suites finally produce alkali-calcic endmembers similar to the AAPG and POPG granitoids (Figure 4.10). C) The older IA+Syn and NHSG (fractionated) mafics are metaluminous and appear to fractionate through the peraluminous field. The diversity exhibited by the NHSG (fractionated) suites (indistinguishable from AAPG suites) places doubt on similar A-type tectonic processes (Chapter 7). References for published Arabian-Nubian Shield fractionated A-type data field and sample suite abbreviations are displayed in Chapter 4.2. All geochemical data are displayed in Appendix 5.
The widely utilised granite classification scheme of Frost et al. (2001) is illustrated in Figure 4.13. IA+Syn suites are clearly magnesian samples with the least evolved granitoids (<65% SiO2) correlating with the lowest ratios of ~0.4. The
151 microgranite/volcanic units of the Subh Suite have the highest values of ~0.7. These suites are predominantly calcic/calc-alkalic in nature and are confined to the metaluminous granite field (exception of peraluminous microgranite/volcanic Subh Suite). This classification is reflective of their magnesian rich hydrous mineralogy.
NHSG suites illustrate the most interesting granite classification because they appear to transition across multiple fields. Figure 4.13 exhibits the transition from magnesian mafic/intermediate granitoid samples (~0.2-0.7) to distinct felsic ferroan alkali-granites (>0.7-0.9) within the same suite. The most evolved samples are perthitic and some even contain aegirine minerals similar to AAPG suites. This highlights the validity of classifying A-type granites as distinctly ferroan. This trend continues with the mafic/intermediate endmembers (similar to IA-syn fields) falling across the calcic/calc-alkalic field. However, unlike the IA-Syn suites, the NHSG (fractionated) suites show a distinct transition into the alkali-calcic realm. Similarly, mafic units are metaluminous, intermediate granitoids are peraluminous and felsic aegirine-bearing alkali-granites are peralkaline. Apart from obvious fractionation trends, NHSG (fractionated) felsic endmembers cannot be separated from AAPG using the Frost et al. (2001) scheme. These resemble different origins and highlight the need for further geochemical separation between the two ferroan endmembers (Chapter 4.4.4).
NHSG (non-fractionated) suites are predominantly ferroan (~0.7-0.9) in nature. This is with the exception of the magnesian (~0.6-0.7) lower silica endmembers of the Ibn Hashbal Suite. All samples are clearly confined to the alkali-calcic field, which are thus far characteristic of all A-type suites sampled in the Shield. As indicated in Figure 4.13, the younger NHSG (non-fractionated) suites mark the possible change in mantle geochemistry from calcic dominated process to more alkaline magmatism. This is discussed further in Chapter 7.2. The hydrous biotite dominated perthitic mineralogy is reflected in the metaluminous-peraluminous granite classification. However, unlike the NHSG (fractionated) or AAPG suites, there is no peralkaline endmembers in this group. This appears to correlate with the absence of aegirine minerals. However, these suites possess all other characteristics of ferroan A-type granite, which highlights the need to further geochemically discriminate these suites (Chapter 4.2.2).
152 The tectonic granite discrimination scheme by Pearce et al (1984a) is illustrated in Figure 4.14. This diagram displays similar fractionation trends to those observed in previous figures. NHSG (fractionated) suites contain the lowest and highest values of any group in this section. These typically range from Rb=~1-180 ppm, Y=~<1-78 ppm and Nb=~2-30 ppm. This group clearly exhibits a trend from VAG related granitoids through to WPG units. It should be noted that the lowest values are mafic endmembers, but are still illustrated to highlight the fractionated nature of the granitic products. The felsic WPG endmembers are aegirine-bearing alkali-granites, whilst the >60% SiO2 samples are perthitic granitoids confined to the VAG field. This highlights the important switch in tectonic setting that is discussed further in Chapter 7.
Figure 4.14: A granite tectonic classification diagram modified from Pearce et al. (1984a). Highlighted in blue and black are NHSG (fractionated) and NHSG (non-fractionated samples respectively, whilst the green older IA+Syn suites from the western part of the Shield. As expected, the green points are confined to the VAG field, but the NHSG (fractionated) suites cross into both the VAG and WPG fields. These clearly show a fractionation trend from a mafic VAG area into a WPG felsic area. Note that the most felsic endmembers are aegirine-bearing alkali-granites and all blue data including mafic endmembers are plotted.The tectonic nature behind the switch between VAG and WPG settings is discussed further in Chapter 7. References for the published Arabian-Nubian Shield I-type and fractionated A-type data fields and sample suite abbreviations are displayed in Chapter 4.2.
IA-Syn units (>60% SiO2) correlate with the lowest trace element values ranging from Rb=~12-67 ppm, Y=~<15-50 ppm and Nb=~2-8 ppm. These units are tightly constrained to the VAG field and possibly represent depleted mantle derived granitoids associated with collision. NHSG (non-fractionated) suites exhibit intermediate to high values ranging from Rb=~62-165 ppm, Y=~<18-80 ppm and Nb=~9-18 ppm. These units hover around the border between VAG/WPG, but creep more into the WPG realm.
153 The two samples in the VAG field are from the ih suite, but also contain 3 samples in the WPG field. The NHSG (fractionated) samples are the youngest suture zone suites and possible help to mark the change in mantle chemistry (Chapter 7.2).
Overall, it is clear that conventional A-type discrimination schemes are not suitable for separating Arabian Shield post-tectonic granitoids associated with suture collision zones. These possess similar geochemical and mineralogical parameters as AAPG suites, but are clearly the result of differing processes. This causes a mixture of granite classifications that overlap into I-S and A fields, classified as both ferroan and magnesian and finally both VAG/WPG. It is clear that these are distinct from older IA+Syn suites, but show geochemical characteristics of both collisional and WPG processes. This is discussed further in Chapter 7.
4.4.3 Western Shield and Nabitah Suture Mafic Endmembers.
Many Plutons sampled and analysed in the Arabian Shield contain mafic (<60%
SiO2) endmembers. Mineralogically, these are predominantly composed of plagioclase, pyroxene, amphiboles and hornblende (Chapter 2), but fractionate to produce distinct felsic endmembers. It is felt necessary to categorise these mafic components to understand further the petrogenetic implications on granite formation. This group has been split into two components: 1) western Shield mafics (WM) including the 867- 829Ma Makkah Suite and 600Ma Rithmah Complex; and 2)Nabitah Suture mafics (NM) including the 636Ma Al Hafoor Suite and the Kawr Suite. Selected endmembers are summarised in Tables 4.2 and 4.3 and all raw data are displayed in Appendix 5.
Previous sections have outlined granitic classification schemes which inherently display fractionation trends. This is particularly obvious with the NHSG (fractionated) suites. Although there are numerous mafic classification schemes, the low titanium nature (<1.2%) of NHSG (fractionated) mafic endmembers reduces the options available for classification. However, two well recognised and robust methods from Pearce et al. (1984b) and Meschede (1986) eliminate the use of major element
154 parameters and successfully categorise units based on the trace elements Cr, Zr, Nb, and Y. Both of these methods are displayed in Figure 4.15.
Figure 4.15: Classification schemes for mafic endmembers sampled in the Arabian Shield. These are all <60% SiO2 and fractionate to produce their respective granitoids described in Figures 4.9-4.14. A) Modified from Pearce et al. (1984b), this utilises Cr and Y concentrations to discriminate MORB and Island Arc Tholeiite (IAT) mafic endmembers. The Kawr Suite shows the most diverse range in Y concentrations from <1-60 ppm. This trend seems to indicate the initiation MORB like melting underneath the Nabitah Suture (west-east Shield collision). These fractionate to produce cumulate gabbros that have been diluted in incompatible elements (accumulation of pyroxene and plagioclase). B) Triangular plot modified from Meschede (1986) which classifies the mantle type chemistry of the mafic endmembers. Note the concentration in ‘D’, which correlates with N-type MORB and the border between ‘C’ and ‘B’, which corresponds with within plate tholeiites and P-type MORB respectively. It should be pointed out that the low Y samples from part A are not plotted because they contain no detectable Nb values. The significance of this mantle chemistry is discussed further in Chapter 7.2. All geochemical data are displayed in Appendix 5.
Suites correlating with WM contain the lowest values of Cr ranging from ~40- 110 ppm. The lowest values correlate with the Rithmah Complex. These suites also exhibit some of the lowest Y concentrations ranging from ~15-30 ppm. As illustrated in Figure 4.15, these are both clearly distinguished using the Y vs. Cr plot of Pearce et al. (1984b). The older Makkah Suite falls onto the bottom edge of the MORB field, while the Rithmah Complex is clearly an IAT suite. This tectonic significance of younger IAT and older MORB mafics is discussed further in Chapter 7. WM suites also contain high
155 Zr concentrations ranging from ~50-110 ppm. Once again the lowest values correlate with the younger Rithmah Complex. However, both suites contain similar Nb values of ~2-6ppm. Figure 4.15 shows the clear placement of these suites firmly into the N-type MORB field of the Meschede (1986) triangular classification scheme.
Suites associated with NM have some of the lowest and highest trace element values of all mafic endmembers. Cr and Y concentrations range from ~45-320 and ~0.3- 56ppm respectively, with the lowest values correlating the Kawr Suite. As illustrated in Figure 4.15, the Al Hafoor mafics are clearly the most Cr rich (~290-320 ppm) suite with moderate Y values (~10-15ppm), and thus correlates with the IAT field. By contrast, the Kawr Suite exhibits a range from Y rich (~35-50ppm) MORB like units to Cr rich (~100-200 ppm), Y poor (~0.3-10 ppm) IAT samples. This figure highlights the fractionation trend of the Kawr Suite from N-MORB melts to cumulate gabbros diluted in incompatible elements.
Unsurprisingly, NM suites also contain a large range in incompatible elements such as Nb and Zr. The Kawr Suite correlates with the highest values of Zr ranging from ~4-187ppm whilst the Al Hafoor Suite has more modest values of ~35 ppm. Similar with Nb, the Kawr Suite ranges from ~0.1-21 ppm and the Al Hafoor Suite contains ~2 ppm. These values are utilised with the triangular classification scheme of Meschede (1986). Figure 4.15 exhibits the placement of the Al Hafoor Suite clearly into the N-type MORB field. The Kawr Suite is similar and shows a cluster in the N- MORB realm, but the majority lie on the border between within plate tholeiites and P- type MORB. However, the trends displayed in the Cr vs. Y diagram favour the within plate tholeiites classification.
Overall, the western Shield and Nabitah Suture mafics exhibit similar mineralogy, but are clearly distinguished into IAT and MORB units using the chemical parameters defined by Pearce et al. (1984b). The mantle geochemistry can be discriminated further into predominantly N-type MORB characteristics, but also within plate tholeiitic affinities with the Nabitah Suture suites. The tectonic significance of these mafic endmembers and their association with producing distinct felsic products is discussed further in Chapters 7 and 8.
156 4.4.4 Geochemistry Summary and Discussion
Table 4.2: A summary of the XRF major element geochemistry for all 20 granitic suites collected in the Arabian Shield. All 137 analysed samples are displayed in Appendix 5 and a procedure is discussed in Appendices a3-a5. The ages of each suite are directly dated zircons from Chapter 3.2. The symbols (bottom) are as follows: AG=Alkali-Granite, G=Granite, M=Monzonite, S=Syenite, GD=Granodiorite, T=Tonalite, D=Diorite, R=Rhyolite (Chapter 2.3). P=Peralkaline, PA=Peraluminous, Metaluminous, AC=Alkali-calcic, CA=Calc-alkalic, A=Alkalic, C=Calcic, F=Ferroan, M=Magnesian (Chapter 4.4). A=Anorogenic, SC=syn-collisional, PO=Post- Orogenic, LO=Late Orogenic, PCU=Post-Collisional Uplift, PPC=Pre Plate Collision (Batchelor and Bowden, 1985). WPG=Within Plate Granite, VAG=Volcanic Arc Granite, OG=Orogenic Granite, ACM=Active Continental Margin, WPVZ=Within Plate Volcanic Zone, OA=Oceanic Arc (Chapter 4.4).
Abanat Al Bad Al Ar Ruway- Mard- Admar Haml Idah Al Khushay- Najirah Ibn Wad- Jar- Rith-mah Shufay- Mallik Subh Al Hafoor Suite Kawr Suite Makkah Suite Suite Suite Hawiyah dah Suite abah Suite Suite Suite miyah Suite Granite Hashbal bah Salajah Complex yah Granite Suite Complex Suite Complex Complex [aa] [abg] [hwg] [ku] [mr] [ad] [hla] [id] [ky] [ao85] [ao88] [kw51p] [kw42] [kw43] [kw14] [nr] Suite [ih] [wb] [dm01b] [dm01c] [js] [rt] [su] [kg] Suite [sf] SiO2 75.04 76.52 71.77 75.36 60.06 60.93 69.39 69.39 63.88 76.00 50.23 75.60 67.05 54.77 44.90 74.45 72.76 71.81 51.81 64.34 73.65 56.13 65.16 74.38 76.00
TiO2 0.36 0.08 0.32 0.06 0.76 0.88 0.31 0.31 0.46 0.09 0.47 0.13 0.76 0.81 0.08 0.15 0.29 0.29 1.21 0.73 0.21 0.65 0.60 0.04 0.11
Al2O3 10.50 12.49 13.94 12.99 18.33 18.47 15.28 15.28 17.81 12.36 17.09 12.93 14.03 15.60 22.42 12.99 13.93 13.08 15.97 15.74 14.00 17.76 15.79 14.10 12.73 Fe2O3 3.14 0.45 0.42 - 1.86 1.66 0.82 0.82 1.58 0.14 2.19 0.04 0.82 1.58 0.95 0.43 0.70 1.06 4.09 2.77 0.70 1.79 1.64 - 0.57 FeO 0.74 0.31 1.73 1.05 2.29 1.48 1.33 1.33 1.09 0.91 6.22 0.75 4.27 5.97 3.50 1.11 0.96 2.23 6.05 2.54 1.29 6.05 2.56 0.61 0.64 Fe# 0.87 0.72 0.79 0.93 0.75 0.63 0.66 0.87 0.59 0.83 0.44 0.85 0.58 0.82 0.24 0.82 0.83 0.94 0.49 0.65 0.72 0.57 0.57 0.05 0.74 MnO 0.04 0.05 0.05 0.02 0.15 0.06 0.06 0.06 0.04 0.04 0.15 0.02 0.10 0.28 0.07 0.02 0.03 0.08 0.17 0.08 0.07 0.14 0.07 0.09 0.03 MgO 0.10 0.13 0.45 0.09 0.84 0.94 0.68 0.68 0.99 0.19 7.78 0.13 1.47 4.28 11.05 0.23 0.40 0.12 6.25 1.36 0.52 4.14 1.92 0.16 0.14 Mg# 0.13 0.28 0.21 0.07 0.25 0.37 0.34 0.13 0.41 0.17 0.56 0.15 0.42 0.18 0.76 0.18 0.17 0.06 0.51 0.35 0.28 0.43 0.43 0.95 0.26 CaO 0.28 0.28 1.38 0.65 3.06 2.22 1.82 1.82 2.64 0.68 9.92 0.61 2.47 16.40 10.70 0.83 1.26 0.95 8.51 3.82 1.99 7.26 4.04 1.08 0.39
Na2O 3.72 4.26 3.48 3.72 6.70 5.08 4.33 4.33 4.96 3.45 2.05 3.74 5.04 0.55 2.04 2.98 3.45 3.70 3.01 4.41 4.60 3.30 4.11 3.32 4.36
K2O 4.81 4.35 5.18 4.91 3.09 6.01 4.69 4.69 4.63 4.89 0.65 5.00 2.26 0.04 0.10 5.70 5.19 5.65 1.03 2.18 1.97 0.63 2.21 5.36 3.86
P2O5 0.01 0.01 0.13 0.01 0.19 0.22 0.09 0.09 0.22 0.02 0.14 0.01 0.27 0.28 0.06 0.06 0.07 0.04 0.26 0.25 0.07 0.15 0.16 0.03 0.02 LOI % 0.46 0.41 0.48 0.46 1.08 0.31 0.37 0.37 0.41 0.62 2.24 0.26 0.36 0.00 3.99 0.36 0.45 0.41 0.96 0.63 0.41 1.74 1.17 0.32 0.45 Total % 99.29 99.38 99.52 99.55 98.69 98.45 99.33 99.33 98.82 99.50 99.83 99.30 99.38 101.12 100.29 99.45 99.50 99.69 100.03 99.15 99.63 100.42 99.74 99.52 99.37
Total No 3 6 5 4 4 4 4 5 5 6 34 4 6 4 3 4 4 3 5 4
Ad Dawa- Ad Dawa- Ad Dawa- Terrane Ha'il Midyan Asir Hijaz Hijaz Afif Ha'il Afif Tathlith Asir Asir Asir Jiddah Hijaz Hijaz Hijaz Hijaz dimi dimi dimi Age (Ma) 585.0 597.4 591.9 612.1 525.6 599.2 608.6 607.9 618.4- 636.0 636-594 631-585 617.6 629- 867-829 710-676 600.0 730-716 599.6 698.7 587.1 601 Rock AG AG G & M G S S M AG M AG AG & G G-AG AG AG GD G & GD D T G R Granite P PA PA & M PA M M M PA PA PA P, PA & M PA M M M PA - M PA - Alkali AC AC & CA AC & CA AC A A AC AC A CA AC & CA AC AC AC CA C - CA AC & CA - Fe or Mg F M & F F F F M M F M F & M F & M F M & F F M M - M F & M - Timing A A SC-PO SC-PO LO LO SC-LO SC-A LO SC-PO A-SC-PO SC-PO SC-PO SC-A PCU SC - PPC SC - WPG- WPG- WPG- WPG- WPG- VAG- VAG- VAG- VAG- WPG-OG- VAG- WPG- VAG- VAG- VAG- Setting ACV/WP VAG-ACM/OA WPG/VAG-ACM VAG- VAG-WPVZ ACM/W - ACM/W - ACM ACM VZ ACM WPVZ WPVZ ACM ACM ACM/OA ACM ACM WPVZ PVZ PVZ ACM
157 Table 4.3: A summary of the XRF and Solution ICPMS trace element geochemistry for all 20 granitic suites collected in the Arabian Shield. All 137 analysed samples are displayed in Appendix 5 and a procedure is discussed in Appendices a3-a5.
Abanat Al Bad Al Ar Ruway- Mard- Admar Haml Idah Al Al Hafoor Najirah Ibn Wad- Jar- Rith- Shufay- Mallik Subh Hawiyah abah Khushay- Kawr Suite Hashbal bah Makkah Suite Salajah mah yah Suite Suite dah Suite Suite Suite Suite Suite Granite Granite Suite Suite Complex miyah Suite Suite Complex Complex Complex [aa] [abg] [hwg] [ku] [mr] [ad] [hla] [id] Suite [ky] [ao85] [ao88] [kw51p] [kw42] [kw43] [kw14] [nr] [ih] [wb] [dm01b][dm01c] [js] [rt] [su] [kg] [sf] Rb 145.4 234.0 190.7 236.5 44.3 40.9 124.8 124.8 107.3 179.1 16.4 109.9 97.0 0.8 2.0 164.9 131.9 62.6 39.8 22.2 28.8 11.8 41.5 118.1 67.1 Ba 24.0 34.7 439.4 19.3 2441.8 2928.3 1195.5 1195.5 1944.5 159.0 228.0 171.0 151.0 91.0 48.0 302.5 587.5 295.8 1268.0 323.0 397.8 128.5 468.0 495.4 764.3 Th 15.7 25.6 14.5 23.7 6.0 1.6 10.0 10.0 17.1 25.6 1.4 4.5 11.5 6.0 0.8 16.9 13.3 5.4 2.0 0.2 3.8 1.1 2.4 9.2 5.9 U 5.9 8.9 7.0 8.8 2.6 1.7 6.0 6.0 4.3 6.2 2.6 2.5 11.4 3.7 1.0 4.1 4.1 3.4 1.1 1.6 1.2 0.6 0.9 2.8 3.6 Nb 71.2 35.6 39.6 37.7 62.2 7.1 6.7 6.7 4.8 7.6 1.8 8.6 29.7 9.6 - 12.8 9.1 19.0 7.8 2.2 4.0 2.7 4.4 4.8 7.2 La 141.7 18.2 34.2 20.3 51.3 51.3 21.5 21.5 20.5 27.0 5.0 21.0 66.0 23.0 - 46.3 56.5 57.8 15.0 7.0 13.8 2.8 11.0 7.6 20.0 Ce 270.7 43.2 76.4 64.8 101.3 95.8 46.8 46.8 35.0 51.0 17.0 51.0 165.0 54.0 1.0 111.5 116.3 129.3 47.0 20.0 34.8 14.3 30.0 22.0 52.0 Pb 20.7 23.4 21.5 29.5 4.2 16.7 16.6 16.6 21.7 23.7 4.4 17.5 8.8 8.6 1.6 28.0 18.9 14.8 4.9 5.9 6.5 2.4 6.0 33.9 8.5 Pr 40.6 4.9 10.0 10.8 11.9 14.6 4.7 4.7 3.8 5.2 1.7 5.6 23.3 6.0 0.1 20.1 16.2 22.0 6.4 2.7 4.2 1.6 4.5 2.9 7.6 Sr 8.1 9.8 126.1 4.7 600.4 894.6 236.3 236.3 679.8 43.9 454.7 47.3 97.2 235.3 429.3 80.1 174.8 23.2 447.0 372.7 198.3 356.0 347.6 158.7 46.5 Nd 121.7 15.2 34.6 49.3 42.0 37.8 16.3 16.3 9.0 15.0 10.0 19.0 102.0 29.0 - 57.8 46.5 72.0 26.0 18.0 15.0 12.8 17.0 7.6 24.0 Zr 770.9 147.2 254.8 110.0 461.8 868.1 226.2 226.2 748.6 101.7 35.2 142.7 295.5 151.8 4.2 223.7 297.8 747.9 336.1 96.6 136.9 57.6 166.5 74.9 171.5 Sm 22.1 3.2 7.9 21.9 8.4 7.9 3.5 3.5 2.3 2.8 1.7 3.6 22.9 5.8 0.2 16.9 7.9 14.1 7.6 3.9 3.3 2.1 4.5 2.4 6.6 Eu 1.1 0.1 1.0 0.1 5.7 3.9 0.7 0.7 1.2 0.2 0.6 0.3 0.5 1.1 0.2 0.6 0.9 3.0 1.9 1.2 0.6 0.7 1.0 0.5 0.6 Dy 12.2 3.8 6.8 35.0 5.5 2.7 2.7 2.7 1.4 2.0 1.5 2.3 15.0 5.3 0.2 14.2 3.3 7.0 7.5 4.5 3.0 2.2 4.1 2.1 6.8 Y 71.2 38.2 46.6 214.7 30.6 11.4 17.3 17.3 9.6 15.2 9.8 11.7 78.6 37.4 0.3 80.5 17.9 36.9 49.8 31.5 21.7 15.2 25.1 20.8 43.6 Yb 6.8 4.6 4.4 17.5 2.2 1.3 1.7 1.7 1.5 1.6 0.9 1.1 5.2 3.2 0.1 7.5 1.5 3.6 4.0 2.7 2.4 1.4 2.7 2.4 5.1 Lu 1.0 0.7 0.7 2.3 0.3 0.2 0.3 0.3 0.3 0.2 0.1 0.2 0.7 0.5 - 1.0 0.2 0.6 0.6 0.4 0.4 0.2 0.4 0.7 0.8 Gd 18.1 3.3 7.2 27.8 7.6 5.8 3.1 3.1 1.9 2.5 1.7 3.0 19.5 5.6 0.2 15.5 6.1 11.1 7.7 4.3 3.1 2.2 4.3 2.1 6.4 Tb 2.3 0.6 1.1 5.6 1.0 0.6 0.5 0.5 0.3 0.3 0.3 0.4 2.9 0.9 - 2.5 0.7 1.4 1.2 0.7 0.5 0.4 0.7 0.4 1.1 Ho 2.4 0.9 1.4 7.4 1.0 0.5 0.6 0.6 0.3 0.4 0.3 0.4 2.8 1.1 - 2.9 0.6 1.3 1.6 1.0 0.7 0.5 0.9 0.7 1.5 Er 6.8 3.2 4.1 20.1 2.6 1.4 1.6 1.6 1.1 1.3 0.9 1.2 6.7 3.2 0.1 7.8 1.7 3.6 4.3 2.7 1.9 1.3 2.6 1.9 4.6 Hf 19.7 7.4 8.0 6.3 5.4 17.6 6.6 6.6 17.7 4.1 1.0 5.3 9.5 4.0 - 8.1 6.9 17.9 8.7 2.7 4.1 1.6 4.7 3.3 6.1 Ta 2.2 1.4 2.2 1.1 3.9 0.4 0.6 0.6 0.5 0.9 0.1 0.5 1.6 0.8 - 1.1 0.8 1.0 0.7 0.2 0.6 0.2 0.5 0.7 0.9 Ga 30.8 21.9 22.4 29.4 21.6 16.2 15.9 15.9 17.8 15.4 18.8 18.7 23.9 20.4 10.4 21.4 19.4 23.5 19.2 18.3 15.4 19.3 16.7 16.0 15.7 Zn 133.0 41.2 63.4 43.5 69.8 48.5 29.0 29.0 33.5 13.0 78.0 17.0 97.0 112.0 22.0 31.0 39.8 122.5 59.0 86.0 37.8 78.0 43.3 9.8 27.7 Cu 8.7 1.5 39.8 4.8 6.3 3.3 6.5 6.5 - 1.0 9.0 - 21.0 12.0 78.0 13.3 8.8 11.8 5.0 38.0 5.8 43.3 5.0 5.8 6.0 Ni - - 0.6 - 0.3 1.8 1.8 1.8 2.0 - 70.0 - 5.0 50.0 323.0 0.3 - - 2.0 55.0 - 18.3 9.3 - - Sc 1.2 2.8 3.4 10.3 7.1 8.1 6.5 6.5 2.8 1.7 36.2 1.8 18.0 22.6 8.4 4.8 3.7 3.5 12.6 31.6 5.6 24.9 12.9 3.7 5.0 Co 125.7 118.2 94.0 112.3 37.0 45.0 82.8 82.8 64.5 115.0 55.0 97.0 65.0 65.0 56.0 111.5 100.5 81.5 81.0 58.0 97.3 48.3 70.7 112.4 113.3 V 2.3 3.8 20.8 3.5 6.5 45.0 19.3 19.3 30.5 5.0 218.0 4.0 53.0 150.0 17.0 8.0 14.7 4.3 48.0 220.0 13.5 188.8 73.0 3.8 4.3 Cr 1.3 1.8 2.8 2.8 - 1.8 5.3 5.3 4.5 1.0 292.0 0.0 17.0 94.0 161.0 2.0 2.0 1.5 3.0 66.0 1.3 40.0 37.7 0.8 1.3 Be 5.9 4.2 3.3 5.3 1.8 0.7 1.3 1.3 1.9 2.4 0.6 1.3 3.0 1.2 0.1 2.6 1.5 1.7 1.3 0.6 1.0 0.3 0.9 1.7 1.4 Cs 2.1 5.9 3.6 8.8 0.7 0.5 8.5 8.5 8.4 7.6 0.6 2.6 1.7 - 0.4 7.3 3.7 3.2 3.2 0.5 0.7 0.4 0.9 6.8 0.4 Mo 1.8 0.8 1.3 0.5 1.6 0.7 0.5 0.5 0.9 0.7 0.2 - 0.1 - - 0.6 0.9 2.5 0.6 0.4 0.7 0.2 0.7 0.5 1.8
158 4.4.4a Subdivision of Arabian Shield A-type Granitoids.
Arabian Shield microplate accretionary cycles are observed in both the western and eastern Shield fragments separated by the Nabitah Orogenic Belt. This significant geological feature marks the collision between western oceanic plates and eastern continental terranes and provides a key focal point for the following discussion.
Arabian Shield A-type magmatism can be subdivided into the following groups:
1) Post-orogenic (~636-600Ma) Perthitic Granitoids (POPG) are absent of Na rich amphiboles/pyroxenes and include the Admar, Haml, Al Khushaymiyah and Idah Suites (Chapter 2). In this discussion the garnet-bearing Malik Granite is also included (intrudes the Idah Suite). These suites are juxtaposed to major sutures (Figure 4.16) and have been classified as VAG, ferroan/magnesian and are high in REE and reflect contamination of N-MORB melts (Chapter 4.2).
2) Nabitah and Halaban Suture Granitoids (NHSG) contain suites that posses Na rich amphiboles and pyroxenes, but also those that don’t. These include NHSG (fractionated) suites such as the Al Hafoor and Kawr Suites and the NHSG (non- fractionated) suites such as the Ibn Hashbal and Wadbah Suites, but also the Najirah Granite in the Ad Dawadimi terrane (Figure 4.16). The key differences are outlined in Chapter 4.2. The NHSG suites have been classified as VAG /WPG, ferroan/magnesian, are very high in REE and reflect contamination of an N-MORB type source (Chapter 4.2.2). Most importantly, NHSG (fractionated) sources are isotopically less juvenile than A-type Groups 1 or 2 (Chapter 4.3). Particular attention is paid to the vicinity of the Khida terrane from which Kawr and Al Hafoor Suites fractionate. These produce two perthitic endmembers: those absent in Na-rich amphiboles (Al Hafoor Suite) and those that contain Na- rich amphiboles (Kawr Suite). The latter show a transition through magnesian VAG to ferroan WPG endmembers. Younger NHSG (non-fractionated) appear to resemble a change in mantle chemistry (Chapter 7).
159 3) Anorogenic (<600Ma) Aegirine Perthitic Granitoids (AAPG) contain suites that posses Na rich amphiboles and pyroxenes, but also those that don’t. These include the Abanat, Al Bad, Al Hawiyah and Ar Ruwaydah Suites (Chapter 2). These are isolated from plate boundaries and are within plate suites (Figure 4.16) classified as WPG, ferroan and are associated with economic deposits. They also contain the highest REE abundance of any group and are derived from isotopically juvenile and enriched mantle with little if any contamination.
It becomes obvious that not all A-type granites are extension related and derived from enriched sources, but invariably involve the interplay of subducting oceanic and continental lithosphere (Nabitah Suture intrusions). This is already suggestive that more than one tectonic process is involved in A-type generation and that Na-rich ferromagnesian mineralogy is not a reliable constraint on petrogenesis, but rather an indication of alkali/iron content in the melt in which they crystallise. The felsic perthitic nature of the endmembers suggests late stage decompression, but this is not necessarily characteristic of within plate aegirine-bearing granitoids (Chapter 2).
Major element geochemistry is similar between all A-type groups, thus only allowing the discrimination between older IA+Syn suites (Chapter 4.2). However, there is obvious distinction between the fractionation of NHSG MORB like mafics and the lateral fractionation of primitive POPG and AAPG syenites. This possibly coincides with the contaminated vs. enriched mantle parental sources that are discussed shortly.
The well recognised discrimination plots of Whalen et al. (1987) utilise major and trace elements to classify granites into I-A and S type categories. As highlighted in Figures 4.9-4.15, IA+Syn suites are ideally separated, but the above A-type groups exhibit considerable overlap with neighbouring I-type fields. This is especially apparent with NHSG suites which cover the lowest I-type realm, but penetrate far out into the A- type field (Figure 4.12). It is acknowledged that mafics (<60% SiO2) are plotted on the Whalen et al. (1987) granite scheme, but these are simply to highlight the fractionation trend only. The felsic endmembers (>60% SiO2) are also plotted and classified as both I-A granites. This highlights the possibility of distinguished tectonic processes, hence mantle sources, involved in generation of A-type granites i.e. highly fractionated and non-fractionated. One might argue that NHSG suites are not true A-type granites, but
160 Figure 4.16: A summary map of the geochemical characteristic of granitic suites sampled in the Arabian Shield. The tectonic setting and ferroan/magnesian parameters were established using classification schemes from Pearce et al. (1984a) and Frost et al. (2001) respectively. These are described in detail in Chapter 4.4. Note the wide range in A-type granites correlating with both suture and within plate related environments, hence they potentially contain different mantle sources. Plutons such as the Kawr Suite are exceptional examples of a transition from VAG + magnesian to WPG + ferroan units within the same felsic endmembers. These provide a clear focal point to compare with classic style WPG ferroan alkali-granites such as the Abanat Suite. rather highly fractionated I-types. However, as pointed out by Whalen et al. (1987) and Eby (1990), A-type granitoids are easily distinguished from I–types by the presence of higher REE abundances regardless of the degree of fractionation. This remains evident
161 with the NHSG suites because they contain characteristic A-type REE and isotope parameters (Chapters 4.2.2-4.3.2).
A new classification by Frost et al. (2001) suggested the term A-type is replaced by ‘ferroan’. This allowed the incorporation of tectonic and mineralogical diversity that are disregarded in the Whalen et al. (1987) scheme. In the case of the Arabian Shield granitoids, this works reasonably well. All the A-type suites are easily discriminated from older IA+Syn magnesian, calc-alkaline, and metaluminous endmembers and are defined as ferroan, alkali-calcic and peraluminous (Figures 4.10 and 4.13). This also highlights some important trends between the A-type groups mentioned above.
NHSG A-types show a clear fractionation trend from magnesian, calcic, and metaluminous mafic endmembers through to both magnesian and ferroan felsic granitoids (Figure 4.13). These appear to follow the same trends as older IA+Syn samples, but produce aegirine-bearing perthitic endmembers. It is acknowledged that Frost et al. (2001) suggest that transition between granite types within a suite is not unheard of, but this suite is interrupted by the onset of younger NHSG non-fractionated) ferroan granitoids. This possibly marks a change in mantle chemistry that is discussed in later sections.
Younger POPG and AAPG suites don’t exhibit fractionation trends synonymous with subducting plates. The primitive syenitic endmembers (~60 wt% SiO2) illustrate a lateral fractionation trend from magnesian (VAG) and ferroan (WPG) granitoids to >70wt% ferroan endmembers (Figure 4.10). These granitoids are also more isotopically juvenile than NHSG (fractionated) mafic endmembers and suggest derivation from a different mantle source. Interestingly, within the Frost et al. (2001) classification diagram (Figure 4.10) the Al Bad and Malik Granite at ~75% SiO2 exhibit vertical dispersion that classifies samples as both magnesian and ferroan granitoids within the same suite. This is deemed is a function of mineral heterogeneity and results in varying magnesian and ferroan values. However, both are considered ferroan due to their geochemical affinity with similar age ferroan suites.
A widely accepted method for classifying A-type granites was proposed by Pearce et al. (1984a). As illustrated in Figures 4.11 and 4.14, this is the best
162 discrimination scheme for the Arabian Shield suites. AAPG granitoids isolated from plate boundaries are categorised as WPG and clearly serrated from suture juxtaposed POPG types classified as VAG. NHSG suites are categorised as both VAG and WPG because they fractionate across all fields. Most importantly, this highlights the possibly of separate tectonic processes involved in generating similar A-type products.
4.4.4b Differentiating Contaminated and Enriched Mantle.
It has become increasingly apparent with data presented in this study, A-type generation involves the interplay of different tectonic processes and mantle sources. There is no question about the post-amalgamation timing of such granitoids, but to simply categorise them as extension related, anorogenic and enriched granitoids does not reflect the geochemical parameters they contain.
One of the best discrimination schemes for the Arabian Shield suites is the use of incompatible trace element and isotopic signatures (Chapters 4.2 and 4.3). Following the tectonic diagrams of Pearce et al. (1984a), incompatible elements such as Nb, Y, Zr and even Nd clearly distinguish AAPG and POPG units and provide the ground work for discrimination (Figures 4.1-4.3). Most importantly, these figures illustrate fractionation trends from N-MORB like mantle that produces IA+Syn, NHSG and POPG suites. These are very distinct from anorogenic AAPG isolated from plate boundaries, which have an enriched (OIB like) source. At no point do even the most evolved NHSG endmembers with similar mineralogy and classifications overlap with the AAPG suites. Note that AAPG suites are not the end products of high fractionation, but are clearly separated using Ce/Yb and Y/Nb ratios (Figure 4.3).
The primitive AAPG syenites, similar POPG syenites and NHSG (fractionated) mafics are all compared to N-MORB and exhibit some clear cut trends (Figures 4.4 and 4.5). Both the NHSG (fractionated) mafics and POPG suites are N-MORB classified/affiliated, have contaminated volcanic arc signatures (large Nb and Eu depletion and lower HREE patterns) and are isotopically distinct from AAPG suites.
163 The most obvious trends are exhibited by the NHSG (fractionated) mafics, which are isotopically less juvenile than both the POPG and AAPG suites and are incorporated into the Paleoproterozoic Khida terrane field (Figures 4.6-4.7). It is suggested that these depleted N-MORB mafics were contaminated by the Khida terrane crust (similar isotopic signature) underneath the Nabitah Belt and fractionated to produce two isotopically distinguished endmembers: perthitic Al Hafoor alkali-granites; and aegirine perthitic Kawr Suite alkali-granites. Most importantly, these mafics are distinguished from POPG and AAPG syenites, which are isotopically more juvenile. POPG and AAPG syenites are of similar composition, but POPG samples are magnesian and reflect contaminated N-MORB geochemistry (Chapter 4.2.3). These fractionate towards perthitic granitoids that are low in HREE and isotopically less juvenile (Figure 4.7). AAPG syenites are ferroan, enriched in HREE and fractionate towards isotopically juvenile aegirine perthitic granitoids that are and are of economic HREE importance.
Overall, this geochemical diversity exhibited by post-orogenic and anorogenic data supports the use of the following terminology to infer about mantle sources and respective petrogenetic processes: 1) Contaminated Mantle (CM) granitoids; and 2) Enriched Mantle (EM) granitoids (Figure 4.17).
The use of Nb (Y-axis) and Y (X-axis) concentrations allows the distinction between any older IA+Syn or younger POPG lineage derived from an N-MORB like source and those that reflect enriched (OIB like) mantle patterns (Figure 4.17). The former incorporates perthitic granitoids that reflect contaminated melts derived from the lower crust i.e. MASH (melting, assimilation, storage and homogenisation) zones (Chapter 7.3), whilst the latter are direct products of asthenospheric (OIB like) upwelling with little or no crustal assimilation. Many Arabian Shield granitoids are of similar age, mineralogy and are derived from juvenile mantle. Thus it is important to emphasise the subtle trace element differences that reflect petrogenetic behaviour.
It should be highlighted that many conventional A-I-S type granites contain similar major element geochemistry, hence, this new scheme utilises more robust incompatible Nb and Y concentrations. Y is also interchangeable with Nd and Zr, which show very similar behaviour during the evolution of a melt (Chapter 4.2.2). It is
164 acknowledged that Pearce et al. (1984a) already uses Nb and Y for granite tectonic discrimination. However, this does not account for fractionation processes, contaminated mantle chemistry or any geochemical transition within a suite resulting from slab tear off style processes (Chapter 7.5).
Figure 4.17: A new mantle classification scheme for the Arabian Shield A-type granitoids based on geochemical parameters defined in Chapter 4.2. The Arabian A-types contain similar mineralogy and geochemistry, but posses different mantle sources. These are not sufficiently differentiated using the Whalen et al. (1987) or Frost et al. (2001) schemes (Chapter 4.4). This diagram is modified from the Pearce et al. (1984a) scheme by the introduction of Nd and Zr parameters, but also eliminates the ‘WPG’ and ‘VAG’ categories. This is instead replaced by enriched mantle (EM) associated with lithospheric delamination and contaminated mantle (CM) associated with MASH zones. This was felt necessary because Arabian post-tectonic and anorogenic granitoids are all classified as WPG or VAG or even both WPG/VAG within the same suite (Chapter 4.4). This diagram separates red AAPG suites from IA+Syn (green), NHSG (blue and black) and POPG (orange) suites. The trace element concentrations used in this diagram are Y=Nb and X=Y. However, alternative element concentrations could be used such as Y=Ta and X=Yb or Nd or Zr as indicated on the diagram, but obviously the separation line and inflection point would adjust accordingly. The basis for the separation line is taken from Pearce et al. (1984a) i.e. tectonic separation based on geochemistry.
Most importantly, this new terminology is not biased towards the Arabian Shield. It is felt that this report contains a sufficient data base to establish new geochemical parameters around other regional A-type suites and shed light on their mantle sources and petrogenesis. This would be useful to anorogenic granites in the Israel area which are thought to resemble fractionation from basaltic melts (Beyth et al., 1994; Jarrar et al., 2008; Figure 4.18). Another possibility is using this scheme on
165 global examples such as the Lachlan Fold Belt, Australia (Figure 4.18). These granitoids could resemble fractionation from a contaminated MASH zone lower crust similar to Arabian granitoids described in Chapter 7.3.
Figure 4.18: The developed classification scheme from Figure 4.17. Top) A-type data bases from various countries forming the Arabian-Nubian Shield (see Chapter 4.2 for references). Note the distinction between the two types of A-type sources. The lower value X and Y data points represent fractionation from contaminated mantle (CM), whilst the higher values represent enriched mantle (EM). The CM data are mainly from Jordan and Israel, whilst the EM data are from Egypt and Yemen. Bottom) The same scheme applied to an extensive data base of granites from the Lachlan Fold Belt, Australia. Red=A-types, green= I-types, yellow= S-types and black=MORB. It is interesting to note the majority of data follow CM fractionation trends. Reference for MORB data are displayed in Chapter 4.2, whilst the Lachlan data base was obtained through the University of Adelaide, Australia. The trace element concentrations used in this diagram are Y=Nb and X=Y. However, alternative element concentrations could be used such as Y=Ta and X=Yb or Nd or Zr as indicated on the diagram, but obviously the separation line and inflection point would adjust accordingly. The basis for the separation line is taken from Pearce et al. (1984a) i.e. tectonic separation based on geochemistry.
166 Chapter 5: Insights into Mantle Source from Zircon Geochemistry.
5.1 Introduction.
The geochronological and isotopic synthesis of zircon data described in Chapter 3, defined 4 discrete tectonic events in the Shield. These comprised the Island Arc (950-730Ma), syncollisional (<730->636Ma), post-orogenic (<636->600Ma) and anorogenic (<600Ma) phases. Detailed wholerock geochemistry (Chapter 4.2 and 4.3) established important trace element and isotopic differences between these suites, which aided in understanding their tectonic significance in the development of the Shield. However, the investigation of trace element behaviour during magmatic evolution, in particular fractional crystallisation, is constrained further by zircon analysis.
One key issue in the petrogenesis of A-type granites is the composition of the upper mantle from which they were derived. Although the mantle beneath the Arabian Shield is isotopically ‘juvenile’, there are arguments for both an enriched and depleted mantle source (Stein and Goldstein, 1996; Be’eri-Shlevein, 2010). Whether or not A- type granites are formed in convergent or extensional settings, they undergo closed system fractionation yielding granites notoriously enriched in incompatible elements. This places difficulties in discriminating source behaviour using conventional whole rock geochemistry.
Zircon is typically a high temperature crystallisation phase (~600-10000C, Chapter 3.2) with petrological evidence for both early and late magmatic crystallisation phases (Chapter 2). Conveniently, this mineral has a tendency for incompatible trace elements to create an ideal monitor for magmatic evolution. Accessory zircon, whether early or late stage, participates in arguably the most fundamental role of trace element distribution in magma crystallization.
Aside from controlling the concentrations of zirconium and hafnium in melts, zircon also strongly effects the distribution of large ionic radii/high charge rare earth
167 elements such as Y, Nb, U, and Th. This is particularly important in fractionation processes in which these REE are incompatible in most silicate mineral phases. Consequently, late stage zircon crystallisation in residual melts controls the abundance of such trace element ratios. This provides a window of opportunity to analyse such ratios to potentially discriminate different zircon sources. Similar zircon studies have been conducted globally by Hoskin and Ireland (2000), Belousova et al. (2002) and Grimes et al. (2007), but exclude the Arabian Shield.
This Chapter aims to utilise zircon grains from a wide variety of granitoid types, tectonic events and geographical locations in the Arabian Shield and potentially identify discriminators that separate zircon sources. Selected concordant zircons from 19 previously analysed granitoids were ablated for trace element data, including multiple zircon morphologies within the same granitoid (Chapter 3.2). These results are summarised in Table 5.1 and displayed in entirety in Appendix 7. The ablation method used is described in Appendix a7.
5.2 Island Arc and Syncollisional Granitoids (IA+Syn).
These suites are the oldest plutonic rocks sampled in the Shield and are characterised by low silica and alkali content, low trace elements and are classified as VAG, calcic and magnesian rich suites (Chapter 4.4). They are also metaluminous characterised by hydrous amphibole mineralogy (Chapter 2). IA+Syn zircon morphology is often separated into stubby prisms and elongate prismatic crystals within the same unit (Chapter 3.2). This provides a window of opportunity to analyse the trace elements of the distinguished morphologies and to link these to magmatic evolution. This group includes the Makkah Suite, Shufayyah Complex, Jar-Salajah Complex and the felsic volcanics of the Subh Suite. The Rithmah Complex is not analysed due to the absence of zircon crystals. Ablated zircon element values are summarised in Table 5.1 and presented in Appendix 7. Cathodoluminescence zircon images with corresponding ablation spots are displayed in Appendix 3.
168 5.2.1 Major Element Geochemistry.
IA+Syn zircons have the highest concentrations of K (~2.7-119 ppm), Al (~1.3- 6235 ppm), Mg (~0.2-431 ppm), P (~252-4651 ppm), Ti (~3.9-917 ppm) and Fe (~18- 8032 ppm) of any intrusive sampled in the Shield. They also contain amongst the highest Na (~7.5-1906 ppm) and Ca (~84-15,985 ppm) concentrations. All the lowest values correlate with the most evolved Jar-Salajah Complex with the exception of Fe, which corresponds with the oldest Makkah Suite gabbro-diorite. The Makkah Suite also has the highest Na, Ca and P levels.
On closer inspection of the individual morphology groups within a given suite some interesting trends occur (values summarised in Table 5.1). The oldest Makkah Suite gabbro-diorite is divided into 3 morphological classes (MC): MC1 stubby poorly zoned; MC2 elongate well zoned; and MC3 elongate poorly zoned (Chapter 3.2). Interestingly, the lowest and highest values of Mg, Al, Ti and Fe correlate with MC3 and MC1 respectively. Conversely, the lowest and highest values of Na, K, P and Ca correspond with MC1 and MC3 respectively. It should be noted that the earliest morphology (MC1) contains more heavy elements and less of the lighter elements, whilst the youngest (MC3) contains less of the heavy and more of the light elements.
This trend continues with the Shufayyah Suite tonalite. This is divided into 3 morphology classes (MC): MC1 stubby poorly zoned; MC2 stubby well zoned; and MC3 elongate well zoned (Chapter 3.2). The lowest and highest values of Na, Mg, Al, Ti and Fe belong to MC1 and MC3 respectively. P, K and Ca are more ambiguous with all MC1, MC2 and MC3 containing lower and higher concentrations of similar levels. Interestingly, the heavy elements seem to show the opposite trend to the Makkah Suite with highest levels in the youngest groups (MC3). The most evolved unit of the Jar- Salajah Complex is also divided into 3 morphology classes (MC): MC1 stubby well zoned; MC2 stubby less zoned; and MC3 elongate well zoned (Chapter 3.2). Similar to the Makkah Suite, this granodiorite has the lowest values of Mg, Al, Ti and Fe correlating to the oldest group (MC1). Conversely, the lowest values of P, K and Ca belong to the youngest group (MC3). The highest values of all major elements, aside
169 from Na, correspond with the middle group (MC2). The lowest and highest concentrations of Na belong to MC3 and MC1 respectively.
Overall, there is a tendency for younger zircon groups to be enriched with lighter major elements such as Na, P, K and Ca, whilst the older zircon groups to be enriched with elements such as Mg, Al, Ti and Fe. The separation of these groups is explored further using incompatible elements, which are described shortly.
In general it is necessary to discriminate the zircon chemistry, hence to discriminate the source of the IA+Syn suites from younger POPG and AAPG suites. As illustrated in Figure 5.2, this is moderately achieved using Na and K concentrations. One of the most striking features is that the majority of the IA+Syn suites are mingling in the perthitic centre field defined by felsic POPG and AAPG endmembers. These contain similar levels of Na and K and show no obvious fractionation trends. Another notable feature is the strong affinity of the oldest Makkah Suite with the youngest AAPG syenite. These show significant mingling, almost indistinguishable from each other. It should be noted that no IA+Syn suites are found at the POPG syenitic end of the field. This close affinity of the IA+Syn suites with AAPG suite endmembers are separated further using incompatible elements as described shortly. The differences in source chemistry and fractionation are discussed further in Chapter 7.2.
5.2.2 Trace Element Geochemistry.
IA+Syn zircons contain the lowest values of Zr (~395,605-593,987 ppm), Hf (~5298-12,305 ppm), Nb (~0.7-10.1 ppm), U (~31-1004 ppm), LREE (~6-1301 ppm) and HREE (~1149-10,274 ppm) of any intrusives sampled in the Arabian Shield. The lowest values exclusively correlate with the oldest Makkah Suite gabbro-diorite, whilst the highest values are predominately from the younger, most evolved (highest wholerock major values) Jar-Salajah Complex. However, the highest values of Zr and Hf correspond with the Makkah Suite and Shufayyah Complex respectively.
As mentioned in the major elements, there are individual zircon groups within granitoid units. These display some interesting trends with incompatible elements. The
170 lowest and highest LREE, HREE, Nb and U abundances within the Makkah Suite correlate with MC3 (youngest) and MC1 (oldest) respectively. This indicates that the oldest group contains the highest concentration of trace elements. Interestingly, the highest Hf and Zr values are held by the youngest age group MC3. A similar trend is displayed within the Shufayyah Complex with the lowest and highest values of LREE, HREE, Nb, Zr and U all defined by the MC1 (oldest) and MC3 (youngest) respectively. The Jar-Salajah Complex is slightly more jumbled with the highest LREE, HREE, Nb and U concentrations correlating with MC2 (middle), whilst the lowest are MC3 (youngest) and MC1 (oldest) respectively. The highest values of Zr and Hf correlate with MC3, whilst the lowest are MC2 and MC1.
One of the most interesting trends exhibited by IA+Syn suites is their age relationship with Hf concentration. As illustrated in Figure 5.1, all suites display a juvenile nature and are clearly separated from the younger more juvenile POPG and AAPG granitoids at ~600Ma. Interestingly, there is a definite trend for increasing REE content with increasing age, which places the IA+Syn suites as the more depleted mantle endmembers. Most importantly, there also appears to be a tendency for an increase in Hf content with decreasing age. This figure highlights the oldest MC1 group zircons containing slightly less Hf content and the younger MC3 groups with more Hf content, hence are more juvenile. This appears to be a common trait with all the granitoid groups that can be subdivided into different age morphologies. The significance of this process is discussed further in Chapter 7.3.
The distinction between IA+Syn suites is pronounced further when utilising incompatible elements. As previously mentioned, these suites have high Na and K concentrations. This creates a strong affinity with AAPG suites and caused some overlap with both POPG and AAPG felsic endmembers. Figure 5.3 again uses Na+K, but is now plotted against LREE abundance. The most obvious pattern is the segregation of the IA+Syn suites to the left hand side containing 100 times less LREE than POPG and AAPG felsic endmembers. Another notable feature is again the overlap of the oldest Makkah Suite gabbro-diorite with the youngest AAPG syenite. This indicates the Na+K concentration of both sources may have been similar. However, this is discussed further in Chapter 7.2.
171 Figure 5.1: Age (Ma) vs. Hf plots for all ablated zircon analyses from 18 different granitic suites. The top left diagram illustrates 4 distinct magmatic events: island arc, syncollisional, post-tectonic and anorogenic phases. Note the large array at ~600Ma synonymous with continental crustal collision and an enriched mantle source. This figure has been broken into two segments: 1) the top right are the suites associated with suture zones. Note the fractionation trends of the black NHSG (non-fractionated) suites and highlighted in a red field the blue NHSG (fractionated) suites. These exhibit 3 distinct chemical groups associated with 3 zircon morphologies within the same suite (become more REE rich with younger age). The appearance of an aegirine-bearing kw51p endmember (light blue) at 608Ma is thought to represent a change in mantle chemistry, possibly linked to slab tearing processes (Chapter 7.3). 2) The bottom left highlights POPG and AAPG endmembers. Note the POPG and AAPG syenites represent the primitive parent endmembers from which fractionation to felsic endmembers occurs and are thought to represent 2 different mantle signatures. All ablation data are displayed in Appendix 7 with complementary zircon cathodoluminescence images in Appendix 3. Sample suite abbreviations are described in Chapter 4.2.
172 Figure 5.2: K vs. Na plots for all ablated zircon analyses from 18 different granitic suites. The top left diagram illustrates 2 distinct syenitic endmembers that appear to overlap and produce a common felsic product. This figure has been broken into two segments: 1) the top right are the suites associated with suture zones such as the Nabitah Belt. The black and blue perthitic suites are thought to be fractionated from an N-MORB type mantle and are interrupted with aegirine-bearing alkali-granites representing a switch in mantle sources (Chapter 7.3). 2) The bottom left highlights POPG containing a Na-K poor syenite parental source. The red AAPG endmembers clearly lie in a Na-K rich zone with an enriched syenitic source. All ablation data are displayed in Appendix 7 with complementary zircon cathodoluminescence images in Appendix 3. Sample suite abbreviations are described in Chapter 4.2.
173 These trends are continued when using Nb, U and Zr incompatible elements. As highlighted in Figure 5.4, the low concentrations of Nb and U found in IA+Syn suites provide one of the most significant examples of source evolution. The data in this figure clearly exhibits two fractionation trends: high Nb/U economic AAPG suites and low Nb/U POPG suites. Most importantly, the green IA+Syn suites are exclusively confined to the lower end of the POPG fractionation trend. The least evolved units clearly overlap the POPG syenite endmembers and fractionate to produce a ~10 fold increase in U. However, these display a somewhat flat stabilisation trend in Nb. It should be emphasised that the primitive IA+Syn and POPG syenite endmembers are ~10 times less rich in Nb than the primitive AAPG syenites. Even the most fractionated Jar- Salajah units are still ~100 times less rich in Nb and U. This clearly shows a depleted non-economic mantle source eventually producing ‘plain’ POPG granitoids. The differences between the enriched AAPG mantle source and depleted POPG/IA+Syn mantle source is discussed further in Chapter 7.2.
Differentiation patterns continue when utilising Nb against Zr as illustrated in Figure 5.5. The IA+Syn suites are confined to the bottom left side of the figure, isolated from more evolved POPG and AAPG felsic endmembers. These appear to be homogeneous in both Nb and Zr showing little evidence of fractionation. This IA+Syn field represents the MORB like mantle chemistry established by whole rock geochemistry in Chapter 4.2. It should be noted that the primitive POPG syenites have a clear affinity overlapping into this field, whilst the primitive AAPG syenite is isolated with enriched Nb levels.
Trace element patterns of all IA+Syn groups are plotted in Figure 5.6. One of the most notable features is the difference between the oldest Makkah Suite gabbro- diorite and most evolved Jar-Salajah Complex granodiorite. All suites, including the similar age Subh Suite rhyolite, are plotted and exhibit a positive enrichment gradient towards HREE. This coupled with the negative Eu anomaly are indicative of fractionation and feldspar segregation processes. The Makkah Suite doesn’t contain Eu depletion, but possesses a very strong positive Ce enrichment not displayed by any other group. This also has the lowest LREE and HREE patterns which support their derivation from an MORB like source as observed by the mafics in Chapter 4.4.3.
174 The slightly more evolved Shufayyah Complex displays similar trends, but is differentiated by the presence of a negative Eu anomaly and elevated LREE and HREE chemistry. The most evolved Jar-Salajah Complex granodiorite is easily distinguished by its large LREE array and elevated HREE. It should be noted that the MC2 zircon group has the highest values, whilst MC1 and MC3 contain the lower spectrum, thus causing a large abundance variation. It should also be mentioned that MC1 group zircons (oldest) do not contribute the negative Eu anomaly, indicating later stages of feldspar removal in MC2, MC3. Overall, these sources are clearly MORB like and their distinction between younger POPG and AAPG suites is discussed further in Chapter 7.
5.3 Nabitah and Halaban Suture Granitoids (NHSG).
Fractionated post-tectonic granitoids provide a focal point for data analysis and discussion because of their suture related nature. Theses suites are characterised by extreme fractionation from IAT mafics through to aegirine-bearing alkali-granites (Chapter 4.2). Consequently this creates amongst the lowest and highest major and trace elements concentrations of any suites sampled in the Shield. This section has been split into the following subgroups: NHSG (fractionated): Al Hafoor and Kawr Suites (oldest suites ~636Ma) characterised by mafic, intermediate and felsic (non aegirine and aegirine-bearing endmembers (Chapter 2) and cover a range in magnesian-ferroan, VAG/WPG, calcic/alkali-calcic and metaluminous-peralkaline classifications (Chapter 4.4); and NHSG (non-fractionated): Ibn Hashbal and Wadbah Suites and the Najirah Granite (resides in Halaban Suture, but age geochemistry is coeval with Nabitah Belt) show evidence of fractionation with strongly ferroan, metaluminous-peraluminous, alkali-calcic and VAG/WPG parameters (Chapter 4.4).
NHSG groups are divided into 3 zircon morphology classes: MC1 stubby well zoned; MC2 elongate well zoned; and MC3 elongate poorly zoned (Chapter 3.2). This provides a window of opportunity to analyse trace elements within the distinct classes and link these to magmatic evolution. Ablated zircon element values are summarised in Table 5.1 and presented in Appendix 7, including the distinguished MC1, MC2 and MC3 zircon morphology classes within the same group. The corresponding cathodoluminescence zircon images and ablation spots are displayed in Appendix 3.
175 Figure 5.3: Na+K vs. LREE plots for all ablated zircon analyses from 18 different granitic suites. The top left diagram illustrates 2 distinct mantle sources producing two different felsic economic endmembers. This figure has been broken into two segments: 1) the top right are the suites associated with suture zones such as the Nabitah Belt. The black perthitic suites are highlighted as a grey field and appear to fractionate from N-MORB type mantle. The blue suites are thought to represent initial fractionation from an N-MORB source, but are followed by aegirine endmembers. This is interpreted as a switch in mantle sources from slab rollback processes (Chapter 7.3). 2) the bottom left highlights volcanic arc perthitic endmembers (orange) overlain with the Nabitah perthitic field. The POPG syenite is thought to represent contamination of an N-MORB mantle that follows a similar fractionation trend producing felsic perthitic endmembers. On the contrary, the red AAPG syenite clearly lies in an enriched zone and follows a lateral fractionation trend to produce felsic aegirine perthitic endmembers. All ablation data are displayed in Appendix 7 with complementary zircon cathodoluminescence images in Appendix 3. Sample suite abbreviations are described in Chapter 4.2.
176 Figure 5.4: Nb vs. U plots for all ablated zircon analyses from 18 different granitic suites. The top left diagram illustrates 2 distinct fractionation trends producing perthitic granitoids (N-MORB source) and aegirine perthitic endmembers (enriched source). This figure has been broken into two segments: 1) the top right are the suites associated with suture zones such as the Nabitah Belt. Note the fractionation from the island arc type granitoids to suites associated with the final collision of the Nabitah Suture. This trend is interpreted to be the result of N-MORB mantle with a transition occurring to an enriched mantle within the same suite (slab rollback process, Chapter 7.3). 2) the bottom left highlights POPG and AAPG suites with the syenites representing the primitive parent endmembers from which fractionation to felsic endmembers occurs. These are thought to represent 2 different mantle signatures that give rise to POPG and AAPG felsic units. The AAPG associated with the N-MORB trend (ku) is non-economic and intrudes N-MORB derived granites (nr), whilst the POPG in the upper line is gold-bearing (id). All ablation data are displayed in Appendix 7 with complementary zircon cathodoluminescence images in Appendix 3. Sample suite abbreviations are described in Chapter 4.2.
177 5.3.1 Major Element Geochemistry.
NHSG (fractionated) suites contain the highest concentrations of Na (~32-760 ppm), Mg (~2.5-2733 ppm), Al (~36-2745 ppm), P (~105-2332 ppm), Ca (~204-3593 ppm), K (~6-652 ppm), Ti (~4.7-150 ppm) and Fe (~44-3866 ppm) from any granitoid in the NHSG field. These are amongst the highest of any suite sampled in the Shield and often nudge the AAPG suite abundance levels. The lowest and highest values correspond exclusively with the Kawr Suite, particularly kw42. However, the slightly more felsic kw51p is higher in Al and Ti and lower in P and Mg. Sample kw42 is divided into 3 zircon morphology classes (MC): MC1 stubby well zoned; MC2 elongate well zoned; and MC3 elongate poorly zoned (Chapter 3.2). Interestingly, the lowest and highest values of Na, Mg, Al, P, Ca, Ti and Fe correlate with MC1 and MC3 respectively. The highest value for K correlates with MC2 and lowest abundance with MC1. It should be highlighted that the youngest zircon morphology (MC3) correlates with the highest abundances of all heavy and light major elements.
NHSG (non-fractionated) suites contain the highest values of Ca (~77-4391 ppm) and Fe (~25-4081 ppm) of any fractionated suite. However, they are slightly lower in Na (~3.4-384 ppm), Mg (~0.4-1307 ppm), Al (~2.7-2232 ppm), P (~111-1538 ppm), K (~2.3-337 ppm) and Ti (~4.1-122 ppm) abundances compared to NHSG (fractionated) suites. The lowest and highest values are slightly more jumbled in this group. The Najirah Granite is the oldest unit and contains the lowest values of Na, Mg, K, Ca and Fe. In addition, it correlates with the highest values of Mg, Al, K and Ti. The slightly younger Ibn Hashbal Suite has the lowest values of P and Ti, but contains the highest Na values. Lastly, the youngest and most evolved Wadbah Suite has the lowest values of Al and highest abundances of P, Ca and Fe.
The analysis of individual morphology groups within the Najirah Granite and Wadbah Suite are summarised in Table 5.1. Firstly, the Najirah Granite is divided in 3 morphology classes (MC): MC1 stubby well zoned; MC2 elongate well zoned; and MC3 elongate poorly zoned (Chapter 3.2). Interestingly, this shows an identical pattern to that of the Kawr Suite. Once again the lowest and highest values of Na, Mg, Al, P, Ca, Ti and Fe correlate with MC1 (oldest) and MC3 (youngest) respectively. MC2 contains the highest values of K and the lowest still correlating with MC1. The Wadbah
178 Suite is also divided into 3 morphology classes (MC): MC1 stubby well zoned; MC2 elongate poorly zoned; and MC3 elongate well zoned (Chapter 3.2). This shows similar patterns with lowest and highest Mg and Fe abundances correlating with MC1 and MC3 respectively. The lowest values of Al and Ti also belong to MC1, but MC2 corresponds with the highest values. Interestingly, Na, P, K and Ca show the opposite trend with the lowest abundances correlating with MC3 and the highest with MC2.
Overall, similar to the IA+Syn suites, there is a tendency for younger zircon groups to be enriched in most major elements. There is some fluctuation with the lighter elements such as Na, P, K and Ca creating an inverse scenario. The separation of these groups is explored further using incompatible elements, which are described shortly.
Zircon chemistry of both NHSG groups display similar characteristics of AAPG suites, therefore it is important to identify source discriminators that separate these suites. As illustrated in Figure 5.2, this is somewhat achieved using Na and K abundances. The first thing to take note of is the overlap of both NHSG groups in the centre domain defined by felsic perthitic endmembers. However, when the data are isolated into separate components there appears to be some obvious trends.
NHSG (non-fractionated) data are easily discriminated from NHSG (fractionated) samples and display a fractionation trend identical to that of the ‘plain’ POPG suites. NHSG (non-fractionated) suites initiate crystallisation at the final collision of the Nabitah Belt (~636Ma) exhibiting low abundances of both Na and K. These follow a fractionation trend exhibiting a 100 fold increase in Na/K terminating at the perthitic zone and are separated by the younger aegirine-bearing Kawr Suite. Most importantly, NHSG (non-fractionated) suites are ‘plain’ perthitic granitoids, thus following the POPG trend. However, these still mark a change is mantle chemistry as discussed in Chapter 7.
Following on from this, NHSG (fractionated) suites overlap the termination of NHSG (non-fractionated) perthitic endmembers. Mineralogically, this makes sense because the 636Ma Al Hafoor Suite is ‘plain’ perthitic alkali-granite. An important factor is the appearance of the aegirine-bearing Kawr Suite endmembers at 608Ma. These contain a ~100 fold increase in Na+K. The Kawr Suite has a strong affinity with
179 the AAPG granitoids, but encroaches slightly into the POPG realm with the older zircon groups. Overall, NHSG (fractionated) suites fractionate from the ‘plain’ perthitic zone defined by the Al Hafoor and older Kawr Suite zircons and are interrupted by the appearance of the aegirine-bearing Kawr Suite endmember (kw51p) at 608Ma. This illustrates a change in mantle behaviour, which is discussed further in Chapter 7.
5.3.2 Trace Element Geochemistry.
NHSG (fractionated) suites contain the highest abundances of Zr (~411,657- 640,539 ppm), Hf (~8032-15,772 ppm), Nb (~2-272 ppm), U (~330-3247 ppm), LREE (~55-2075 ppm) and HREE (~1108-10,785 ppm) of any NHSG unit. Some elements are also in the same league as the AAPG suites. The lowest and highest Hf, LREE, Nb and Zr values correlate with the Kaw Suite (kw42 and kw51p respectively). Interestingly, sample kw51p (youngest) has the lowest HREE and U abundance, whilst the highest values correspond with sample kw42. Within the Kawr Suite, zircon morphology groups correlate well with the major elements and similarly with trace elements. The lowest and highest abundances of Hf, LREE, Nb, Zr and HREE correspond with the oldest (MC1) and youngest (MC3) groups respectively. U is the exception with MC2 (middle) and MC3 correlating to the lowest and highest respectively.
NHSG (non-fractionated) suites contain lower abundances of Zr (~417,581- 560,098 ppm), Hf (~6958-15,751 ppm), Nb (~1.8-114 ppm) and U (~67-2572 ppm), but higher LREE (~21-3984 ppm) and HREE (~1042-13,795 ppm) than that of NHSG (fractionated) suites. The lowest and highest values of Nb, Zr and LREE are the Najirah Granite and Ibn Hashbal Suite respectively. Conversely, the lowest and highest values of Hf and HREE are the Ibn Hashbal Suite and Najirah Granite. The Wadbah Suite and Najirah Granite contain the highest and lowest abundances of U respectively. Trace element inspection of the Najirah Granite 3 zircon morphologies yields a similar result to that described for the major elements. The lowest and highest abundances of Hf, LREE, Nb, Zr, U and HREE correlate with the oldest MC1 and youngest MC3 zircon populations respectively. This follows suit with the Wadbah Suite for Hf, Nb, U and HREE concentrations. Zr and LREE display the opposite trend with the oldest (MC1) and youngest (MC2) groups corresponding with the highest and lowest respectively.
180 A very significant trend is exhibited by both NHSG groups when their age and Hf concentration values are explored. As illustrated in Figure 5.1, all units contain a juvenile nature, but there are subtle differences exhibited within the zircon morphology. NHSG (non-fractionated) suites show a distinctive fractionation curve initiating with Hf values of ~6000 ppm and terminating at ~15,000 ppm. Interestingly, the oldest zircon morphologies (MC1) are the least juvenile and show a clear trend towards increasing juvenility with the youngest zircons (MC3). NHSG (fractionated) suites also exhibit this trend of increasing juvenility with the youngest zircon groups, but show a significant difference. The Al Hafoor Suite and oldest Kawr Suite zircons define the least juvenile field at 636Ma with the lowest Hf abundance of ~8000 ppm. This is discretely followed by the MC2 (middle) zircon populations at ~10, 000 ppm. Finally, the youngest zircon populations appear at ~12,000 ppm coupled with the aegirine-bearing endmembers at 608Ma with levels of ~15,000 ppm. Most importantly, there is a tendency for increasing juvenility with decreasing age and each Kawr Suite zircon population can be easily discriminated without overlap. This significant feature is explored further below using various incompatible parameters and discussed in Chapter 7.2.
As previously mentioned, NHSG (non-fractionated) suites have a strong affiliation with POPG suite trends when using Na and K parameters. This trend is also pronounced with the addition of LREE chemistry. As illustrated in Figure 5.3, NHSG (non-fractionated) suites show a positive linear fractionation trend highlighted in grey. This initiates at ~630Ma with low abundances of Na+K (~10 ppm) and LREE (~50 ppm) constrained by the oldest zircons. These continue to fractionate towards the youngest zircon population with N+K and LREE values of ~500 ppm and ~1000 ppm respectively. The NHSG (non-fractionated) samples define the fractionation trend to which POPG suites show similar behaviour. NHSG (fractionated) suites begin to appear at LREE abundance levels of ~100 ppm and Na+K values of ~50 ppm (Figure 5.3). Interestingly, the ‘plain’ perthitic Al Hafoor Suite and older zircon populations of the Kawr Suite initiate at ~636Ma and show a liner fractionation pattern mimicking that of NHSG (non-fractionated) suites. However, this is interrupted by Na+K and LREE levels of ~1000 ppm exhibited by the younger aegirine-bearing endmembers. These units have a strong affinity with AAPG suites and are thought to represent a change in mantle chemistry (Chapter 7).
181 One of the most significant trends displayed by both NHSG groups becomes apparent when utilising Nb, U and Zr incompatible elements. As mentioned in other sections, Figure 5.4 shows two fractionation trends: high Nb/U economic AAPG suites and low Nb/U POPG suites. The latter trend is defined by IA+Syn and POPG suites which fractionate to produce ‘plain’ perthitic endmembers, whilst the former produces AAPG aegirine-bearing alkali-granites. NHSG (non-fractionated) suites are confined to the lower end of the aegirine fractionation trend, containing ~100 ppm U and ~1-10 ppm Nb. These show a somewhat positive linear fractionation towards ~1000 ppm U and ~100 ppm Nb. Interestingly, the oldest zircon populations at ~630Ma contain the lowest abundances and fractionate towards high concentrations defined by the youngest zircon populations.
NHSG (fractionated) samples initiate at ~636Ma and appear just after the IA+Syn granitoids containing ~1ppm Nb and ~1000 ppm. This is strictly defined by the oldest MC3 Kawr Suite and Al Hafoor Suite zircons. These are following the ‘plain’ perthitic fractionation path as justified by their mineralogy. Interestingly, there is a sudden jump into the aegirine perthitic field defined by the MC2 and MC3 Kawr Suite zircons. These show no increase in U, but increase in Nb by roughly 10 times. Finally, the aegirine-bearing kw51p sample is isolated at the top of the aegirine fractionation trend. Once again this displays a ~10 fold increase in Nb abundance (Figure 5.4). This obvious change in Nb abundance between morphology groups is not observed in any other suite. The change between ‘plain’ perthitic fractionation and aegirine fractionation trends within the same suite is a clear indication of changing source behaviour which is discussed further in Chapter 7.
This trend is again illustrated in Figure 5.5 which plots Nb against Zr abundance. NHSG (non-fractionated) suites have a strong affiliation with the N-MORB field created using the IA+Syn suites. These units overlap into this field and produce a spread from ~450,000-550,000 ppm Zr. Interestingly, the oldest zircon populations show the lowest concentrations of Nb (~1-10 ppm) and fractionate to the youngest zircon populations at ~100 ppm Nb. More significant, is the separation within the NHSG (fractionated) samples. These suites show a discrete transition from the Al Hafoor Suite and oldest Kawr Suite zircons through to the younger zircon populations. It should be noted that the oldest groups contain the highest Zr levels (~600,000 ppm)
182 and lowest Nb levels (~5 ppm). Interestingly, the youngest zircon populations display a drop in zirconium abundance to ~470,000 ppm, but a rise in Nb levels to ~10 ppm. The youngest aegirine-bearing endmember have similar zirconium levels, but again increases in Nb to ~100 ppm. Once again, there is a clear change is source behaviour which is discussed in Chapter 7.
Trace element patterns of all fractionated groups are plotted in Figure 5.6. Both NHSG groups display positive enrichment towards HREE. These are coupled with a strong negative Eu anomaly and are both indicative of fractionation and segregation processes. There is very little difference between HREE patterns, but there are significant variations in LREE. One of the most notable differences is the lower abundance of LREE in the younger NHSG (non-fractionated) suites. More specifically, within NHSG (non-fractionated) suites, there is a depletion of La followed by a strong enrichment in Ce and Sm. This lower abundance in LREE is clearly confined to the Najirah Granite and Wadbah Suite. The lowest values are defined by the oldest zircon morphology MC1 groups and increase towards the youngest zircon populations. These LREE patterns are very similar to POPG N-MORB patterns of the IA+Syn suites. The Ibn Hashbal Suite however, is clearly enriched compared to these suites and is mingling with the aegirine-bearing endmembers of the Kawr Suite. This is suggestive of a change in mantle chemistry and is discussed further in Chapter 4.4.4.
The older NHSG (fractionated) units display somewhat similar trends, but contain subtle differences that allow separation. The ‘plain’ perthitic Al Hafoor Suite forms the upper boundary of the POPG like chemistry and is clearly lower in both LREE and HREE than the Kawr Suite. The Al Hafoor Suite and younger Najirah Granite and Wadbah Suite form the boundary between ‘plain’ perthitic and enriched perthitic granitoids. Despite the fact the Najirah Granite and Wadbah Suite encroach into this field (younger MC3 zircon populations), this boundary is considered to mark the change in LREE patterns, hence mantle chemistry beneath the Nabitah Belt (Chapter 7.2).
183 Figure 5.5: Nb vs. Zr plots for all ablated zircon analyses from 18 different granitic suites. The top left diagram illustrates 2 distinct mantle sources producing two different felsic endmembers. This figure has been broken into two segments: 1) the top right are the suites associated with suture zones such as the Nabitah Belt. The black perthitic suites are thought to be fractionated from an N-MORB type mantle. The blue suites are thought to represent initial fractionation from an N-MORB source, but are followed by aegirine endmembers. This is interpreted as a switch in mantle sources from slab rollback processes (Chapter 7.3). 2) the bottom left highlights POPG suites overlain with the N-MORB field. The POPG syenite is thought to represent contamination of an N-MORB mantle while the red AAPG syenite clearly lies in an enriched zone. These two syenites fractionate to produce perthitic (POPG) and aegirine perthitic (AAPG) felsic endmembers. All ablation data are displayed in Appendix 7 with complementary zircon cathodoluminescence images in Appendix 3. Sample suite abbreviations are described in Chapter 4.2.
184 Figure 5.6: Primitive mantle normalised REE patterns of ablated zircons from 18 different granitic suites. A) IA+Syn suites of the Jiddah and Hijaz terranes respectively with a MORB like signature (dm) unit and LILE enrichment in the youngest units. This is thought to represent contamination of a MORB like parent followed by fractionation cumulate processes (negative Eu). A volcanic extrusive (sf) from the Hijaz region is used for comparison. B) NHSG suites with a MORB like signature that is associated with the final collision at ~636Ma. Fractionation cumulate processes are also evident within the Kawr and Wadbah Suites and Najirah Granite, with older populations thought to represent changing mantle chemistry, hence slab tear off. C) POPG and AAPG suites representing continental arc and lithospheric mantle affinities respectively. Note the two primitive syenitic parents (mr, ad) that produce fractionated perthitic and aegirine-bearing endmembers. The AAPG suites contain enriched LILE and HREE patterns compared to the non-economic POPG suites. This is thought to represent a change in mantle chemistry from a contaminated N-MORB signature to an asthenospheric MORB like signature. This is discussed further in Chapter 7.2. Primitive mantle normalising values are taken from Sun and McDonough (1989). Sample suite abbreviations are described in Chapter 4.2.
185 5.4 Post-Orogenic Perthitic Granitoids (POPG).
Similar to AAPG suites, POPG suites contain high major and trace elements abundances. These are also peraluminous and alkali-calcic in nature, but are predominantly magnesian (Chapter 4.4). Mineralogically, they are also perthitic, but are absent of Na-rich amphiboles (Chapter 2). POPG zircon morphology is somewhat similar, defined by elongate crystals, but they appear to lack the oscillatory zoning present in AAPG crystals (Chapter 3.2). This scenario creates difficulties in the separation of POPG from AAPG suites. However, as illustrated in Chapter 4.2, these are separated using incompatible elements and indicate two different sources. This creates the ideal scenario to distinguish their sources using zircon trace elements. This group includes the Admar Suite, Haml Suite, Idah Suite and Al Khushaymiyah Suite. The crustally derived garnet-bearing Malik Granite is also included here as it intrudes the Idah Suite. Ablated zircon element values are summarised in Table 5.1 and presented in Appendix 7. Cathodoluminescence zircon images with corresponding ablation spots are displayed in Appendix 3.
5.4.1 Major Element Geochemistry.
POPG zircons contain the lowest concentrations of Na (~3.4-466 ppm), K (~2.4- 708 ppm), Al (~2.5-2009 ppm) and Mg (~0.2-431 ppm) of any granitoid sampled in the Shield. The lowest and highest values correspond with the least evolved Admar syenite and most evolved Idah alkali-granite respectively. Interestingly, the crustally derived Malik Granite contains the lowest values of Na (~27-146 ppm), K (~5.8-282 ppm), Al (~37.6-370 ppm), Mg (~7.3-184 ppm), Ca (~253-1475 ppm), P (~282-576 ppm), Ti (~4.3-27 ppm) and Fe (~70-714 ppm) displayed by any group. It must be pointed out that the lowest values are the most tightly concentrated of any group. This produces small concentration ranges synonymous with a largely unfractionated melt. Returning to the POPG units, these contain similar Ca (~71.4-11,594 ppm), P (~69-4060 ppm), Ti (~5.6-268 ppm) and Fe (~41-6695 ppm) to that of AAPG suites. Interestingly, the Fe is actually ~2000 ppm greater than AAPG suites, whilst the Ca is ~10,000 ppm lower than
186 AAPG suites. Once again the lowest and highest values correlate with the most primitive Admar syenite and most evolved Idah alkali-granite respectively.
The separation of AAPG and POPG suites is proven difficult because of their similar mineralogy, age and chemical parameters (Chapters 2, 3.2 and 4.2). However, there are subtle differences in major and trace elements chemistry, particular in the similar primitive syenitic endmembers, which indicate a separate discrete evolution from two different sources. It was therefore necessary to establish differentiated source evolution trends using zircon elements. Figure 5.2 illustrates the clear separation of POPG and AAPG syenitic endmembers, which display two differentiated fractionation trends producing overlapping similar felsic endmembers. The Admar Suite is very low in Na (~3.4-10.5 ppm) and K (~2.4-27.7 ppm) and has roughly 100 times less Na and 10 times less K abundance than that of the AAPG syenite. POPG suites display a fractionation curve increasing in both Na and K with more evolved samples. This is roughly a 10 fold increase most likely due to the fractionation and crystallisation of alkali-feldspars (felsic perthitic endmembers). It should be noted that the AAPG suites show a ~10 fold decrease in Na concentration due to crystallisation of Na amphiboles. This clearly shows two different evolutionary trends overlapping in the central economic zone. This is discussed further in Chapter 7.2.
5.4.2 Trace Element Geochemistry.
Zircons confined to POPG suites contain similar, but slightly lower values of Zr (~471,306-659,817 ppm), Hf (~7260-13,437 ppm), Nb (~0.5-317 ppm), U (~31-2673 ppm), LREE (~19-2778 ppm) and HREE (~600-12,142 ppm) compared to that of AAPG suites. Once again, the lowest and highest values correlate with the Admar syenite and most evolved Idah alkali-granite. The Haml Suite contains the lowest LREE values, but also the lowest and highest Zr values. The crustally derived Malik Granite contains the lowest values of Zr (~504,166-545,989 ppm), Hf (~6488-17,006 ppm), Nb (~12.7-36 ppm), U (~363-884 ppm), LREE (~87-804 ppm) and HREE (~2774-5919 ppm) of any sample in the Shield. One exception is Nb, which is slightly higher than the IA-Syn group. Similar to the major elements, these produce small concentration ranges
187 synonymous with a largely unfractionated melt. This is not surprising because the Malik Granite intrudes the most evolved POPG suite (Idah Suite).
POPG suites yield a similar trend to AAPG suites when utilising Hf values and their post-tectonic ages. As highlighted in Figure 5.1, all POPG suites display a juvenile nature and become increasingly more juvenile with the more evolved endmembers, which overlap the AAPG suite field. The majority of the POPG units (including the POPG syenite), plot outside the AAPG field and show vertical fractionation trends. Most importantly, these display similar values to that of N-MORB derived IA+Syn groups.
The distinction between POPG and AAPG suite sources becomes pronounced when using incompatible elements. As mentioned above, there is a clear separation between these groups when utilising Na and K. As illustrated in Figure 5.3 these are plotted against LREE (excluding Y) and exhibit some distinct fractionation trends. The POPG syenite is ~100 times less rich in Na+K than that of AAPG suite, but fractionates to produce similar felsic endmembers. Most notable, the POPG suites have a positive liner fractionation trend increasing in Na+K and LREE concentrations to similar AAPG suites levels. This is distinct from the AAPG suites which display a lateral fractionation trend remaining constant in Na+K, but yields similar perthitic products.
Fractionation trends are continued when using Nb, U and Zr incompatible elements. Figure 5.4 highlights the differences between POPG and AAPG suite Nb and U concentrations. The figure is split into two fractionation trends separated by Nb contents. The POPG syenite is ~10 times less rich in Nb than the AAPG syenite, but also shows a 100 fold increase in U concentration towards felsic endmembers. However, the POPG fractionation trend is much lower in Nb even in the most evolved samples. This trend incorporates most POPG suites (including an AAPG suite) which are non-economic. The Idah Suite is the most evolved POPG suite and is slightly economic (gold-bearing), hence is found in the AAPG trend above. Figure 5.5 exhibits a similar pattern with Nb and Zr, but the felsic endmembers overlap. The POPG suites show a vertical fractionation trend from the N-MORB like field composed of the IA+Syn suites. This trend increases in Nb towards felsic products, but unlike the AAPG suites, displays little variation in Zr.
188 Trace element patterns of both the POPG and AAPG endmembers together with the respective felsic endmembers fields are plotted in Figure 5.6. Both groups exhibit LREE enrichment, a slight Eu depletion and a positive gradient towards HREE. This trend is synonymous with fractionation/segregation of incompatible HREE in the melt. There is no obvious difference in primitive endmember element behaviour, but the POPG syenite has slightly lower HREE patterns. This is also reflected in their felsic products with the key differences portrayed in the lower LREE and HREE chemistry exhibited by the POPG suites. The crustally derived Malik Granite is also plotted to help emphasise the less evolved syenites. Unsurprisingly, this has higher LREE, similar HREE and also a slight Eu anomaly synonymous with feldspar fractionation. This granite intrudes the highly evolved Idah Suite and as a result, is confined to the POPG realm mimicking similar REE patterns. Overall, subtle differences in REE coupled with strong major element trends, suggest different POPG and AAPG sources that generate similar felsic products (Chapter 7.2)
5.5 Anorogenic Aegirine Perthitic Granitoids (AAPG).
As established in Chapter 4.2, AAPG suites are defined by their high incompatible trace elements, in particular, Nb, Rb, Nd, Y and high HREE chemistry. They are aegirine-bearing, ferroan, alkali-calcic, and predominantly peraluminous in nature. The zircon morphology is characterised by elongate and oscillatory zoned crystals (Chapter 3.2). Zircon populations are limited and as a consequence, not all suites in this group were analysed. The following AAPG suites define the zircon chemistry in this group: Al Bad Granite Super Suite, Al Hawiyah Suite, Ar Ruwaydah Suite and the Mardabah Complex. Ablated zircon element values are summarised in Table 5.1 and presented in Appendix 7. Cathodoluminescence zircon images with corresponding ablation spots are displayed in Appendix 3.
189 5.5.1 Major Element Geochemistry.
Zircons in this group contain amongst the highest concentrations of all elements measured by laser ablation. Most noted are the Na (~21-3295 ppm), K (~5.2-1167 ppm) and Ca (~157-21102 ppm) values, which are the highest of any group. Interestingly, the lowest and highest values of Ca correspond with the highly evolved Al Hawiyah Suite and least evolved Mardabah syenite respectively. The most evolved Al Hawiyah and Ar Ruwaydah Suites occupy both the lowest and highest Na and K values. These trends are also reflected in Al (~4.9-3342 ppm), Mg (~0.5-1543 ppm), P (~170-4406 ppm), Ti (~5.2-225 ppm) and Fe (~31-4328 ppm) concentrations with the lowest and highest values correlating with the Ar Ruwaydah and most evolved Al Bad Suites respectively.
One of the key issues regarding AAPG and POPG suites is their geochemical separation which is proven difficult because of similar whole rock mineralogy, age and chemical parameters (Chapters 2, 3.2 and 4.2). However, there are subtle differences in major and trace elements chemistry, particular in the similar primitive syenitic endmembers, which indicate a separate discrete evolution from two different sources. It was therefore necessary to establish differentiated source evolution trends using zircon elements. Illustrated in Figure 5.2 is the mixing of AAPG and POPG felsic endmembers that clearly arise from two differentiated fractionation trends. The AAPG Mardabah Complex syenite is very high in Na (~955-2370 ppm) and K (~113-204 ppm), which is roughly 100 and 10 times greater than that of the POPG syenite. The AAPG suites exhibit lateral fractionation from this syenite endmember and decrease in Na by a magnitude of 10. This is presumably the crystallisation of Na-bearing amphibole minerals extracting Na from the melt. In contrast, POPG suites show an increase in Na by a factor of ~10. Both felsic endmembers overlap in the central economic zone, but clearly originate from different sources (Chapter 7.5).
190 5.5.2 Trace Element Geochemistry.
AAPG suites contain the highest zircon trace element concentrations of any granitoid group and this section will focus on the incompatible elements that can easily distinguish these granitic groups. AAPG zircons have the highest Zr (~465,892- 1,665,984 ppm), Hf (~4746-15,090 ppm), Nb (~2.6-411 ppm), U (~76-11,458 ppm), LREE (~42-6361 ppm) and HREE (~1455-15,258) concentrations of any group sampled in the Arabian Shield. The majority of lowest and highest REE values correlate with the primitive Mardabah Complex and highly evolved Al Bad Suite respectively. This is of course with the exception of Zr for which the scenario is reversed.
When utilising AAPG crystallisation ages against Hf content, there is an interesting trend of juvenility displayed in Figure 5.1. The 600Ma AAPG suites have the highest Hf values of any group, thus they are the most juvenile. Most importantly, these are distinct from the N-MORB derived syncollisional granitoids. They also exhibit little fractionation, plotting as a homogeneous zone, but are thought to be derived from a source similar to the 525Ma primitive AAPG syenitic endmember. The distinction between AAPG and POPG suites is not that definite using these parameters, but indicate that the majority of the POPG suites plot outside the AAPG realm.
The distinction between POPG and AAPG suite sources becomes quite clear when utilising incompatible elements. As described above, Na and K are particularly useful for separating the POPG and AAPG suite trends. Following on from this, LREE (excluding Y) are plotted against Na+K in Figure 5.3. One of the most striking factors is the difference in Na+K concentration between the AAPG and POPG primitive endmembers, which is ~100 times greater for the AAPG syenite. Both exhibit fractionation trends yielding a similar felsic perthitic product. However, the AAPG suites show a lateral increase in LREE, but remain constant in Na+K.
Similar trends are illustrated when incompatible elements such as Nb, U and Zr are used. As illustrated in Figure 5.4, Nb vs. U contains two fractionation trends separated by the differences in AAPG and POPG syenites. The first trend incorporates the majority of the AAPG suites and one economic POPG unit and shows a tendency
191 for Nb enrichment towards the most evolved and economic endmembers. It is clear that not all AAPG suites are confined to this trend because of the placement of the highly evolved Ar Ruwaydah Suite at the termination of the lower Nb POPG trend. Conveniently, however, this is not a significant REE economic suite, suggesting that the placement is justified. Most importantly, the AAPG suites are ~10 times higher in Nb and are clearly separated from POPG units. Figure 5.5 utilises both Nb and Zr to highlight similar patterns of separation. Once again, AAPG suites show a lateral fractionation from the high Zr syenitic endmember and an increase in Nb towards the felsic termination point. Most importantly, this is not displayed by the POPG trend which shows a vertical fractionation towards similar felsic endmembers.
The trace element patterns of both the AAPG and POPG endmembers together with the respective felsic endmembers fields are plotted in Figure 5.6. Both groups exhibit LREE enrichment, a slight Eu depletion and a positive gradient towards HREE. This trend is synonymous with early feldspar segregation and fractionation of incompatible HREE in the melt. There is no obvious difference in primitive endmember element behaviour, but the AAPG syenite has slightly elevated HREE patterns. This is also reflected in their felsic products with the key differences portrayed in the elevated LREE and HREE chemistry exhibited by the AAPG suites. Overall, subtle differences in REE coupled with strong major element trends, suggest different AAPG and POPG sources that generate similar felsic products. This is discussed further in Chapter 7.5.
192 5.6 Zircon Geochemistry Summary.
Table 5.1: A summary of zircon LA-ICPMS trace element data obtained from 18 dated magmatic suites across the Arabian Shield. All zircon analyses and corresponding CL images are displayed in Appendices 7 and 3 respectively. Values were processed using ‘Glitter’ software (Van Achterbergh et al., 2001) with procedural details described in Appendix a7. The symbol ‘MC’ designates the zircon morphological classes within a given suite. The Abbreviations ‘WPG’ and ‘VAG’ correspond with Within Plate Granite and Volcanic Arc Granite respectively (Chapter 4.4). The U-Pb age presented under the symbol ‘MC’ correlates to populations of zircons within the same suite containing the same morphology.
Al Bad Suite Mardabah Ar Admar Haml Suite Idah Suite Malik Al Hafoor Kawr Suite Al Hawiyah Suite [hwg07] Al Khushaymiyah Suite [ky129] Kawr Suite [kw42] Ruwaydah Complex Suite Granite Suite [abg179] MC1 MC2 MC3 [mr191] [ku139] [ad194] [hla110] [id159] MC1 MC2 MC3 [kg150] Suite [ao85] MC1 MC2 MC3 [kw51p] Na23 235.3 39.7 184.2 529.5 1540.8 1311.3 6.7 43.8 181.8 39.9 31.9 62.5 68.6 125.5 139.3 188.2 306.4 197.5 Mg24 385.0 691.9 247.4 475.1 54.2 93.3 5.8 85.1 101.6 65.8 98.0 189.8 61.1 21.7 71.0 326.2 805.4 102.6 Al27 1367.7 998.3 1021.1 1061.6 106.4 785.1 25.7 214.3 748.5 262.5 302.8 400.6 208.4 184.6 227.1 509.0 880.4 828.7 P31 1032.8 227.8 522.9 562.0 1545.1 983.4 184.5 1275.4 1350.3 427.2 292.3 262.6 398.9 637.5 563.5 652.4 776.2 337.7 K39 268.7 26.1 218.4 53.1 148.7 273.5 4.9 38.6 172.8 24.5 26.5 34.8 118.1 55.8 96.6 155.9 124.7 134.8 Ca43 1340.9 253.9 1386.5 2103.6 10755.5 8251.7 116.3 3366.6 5331.4 458.5 325.6 610.5 561.2 1510.8 1386.5 1729.1 1775.2 1357.9 Ti49 45.1 36.1 30.0 25.0 61.8 44.9 18.2 22.1 52.5 29.6 19.6 15.2 14.5 14.9 18.9 29.2 34.7 41.5 Fe57 943.1 1448.6 658.6 1580.4 733.8 1563.6 345.6 400.6 2735.2 593.5 742.2 933.1 277.1 477.2 282.2 757.4 1516.7 1031.2 Rb85 2.3 0.3 2.1 0.7 0.3 0.8 0.1 0.3 1.3 0.4 0.3 0.2 1.0 0.3 0.7 0.5 0.6 1.0 Sr88 24.1 2.0 12.6 34.4 1.9 101.9 0.3 3.3 30.2 6.1 2.1 7.0 2.3 5.7 3.3 7.0 11.4 14.1 Y89 5570.3 1643.8 3155.1 5131.3 1439.9 2499.5 641.1 824.6 3426.9 3107.3 1674.2 1286.0 3295.1 1882.0 2167.1 2622.2 2696.3 2857.6 Zr90 521911.9 495319.3 504011.6 519189.7 937438.9 564121.9 545941.0 535709.1 556759.4 494120.0 494820.3 497765.9 530947.8 580341.8 501999.6 517436.2 544058.3 484384.3 Nb93 43.0 63.5 172.6 206.9 12.5 9.2 0.9 2.5 70.9 6.2 3.1 3.2 21.8 4.7 7.3 10.3 12.2 89.7 La139 111.9 8.5 28.3 142.6 0.7 130.0 0.7 25.7 169.9 47.9 18.0 59.5 20.2 18.1 11.9 43.6 39.3 25.5 Ce140 1675.3 33.4 115.0 284.8 18.6 527.0 41.4 96.1 296.1 328.7 135.0 241.0 134.2 78.0 65.8 140.8 171.1 161.6 Pr141 54.6 3.0 14.6 33.6 0.4 71.2 0.4 12.7 36.4 13.7 5.8 15.4 10.1 9.6 6.9 18.0 24.3 25.1 Nd146 263.5 19.8 81.2 155.9 5.3 467.1 5.4 71.9 182.7 72.3 29.2 71.0 63.8 51.6 42.7 102.1 133.7 155.3 Sm147 145.5 15.5 39.4 52.0 8.6 185.5 7.4 25.5 90.0 40.9 13.7 17.5 42.4 33.9 32.9 59.7 64.4 110.9 Eu153 6.9 1.8 7.0 4.8 1.2 11.8 2.0 1.7 3.7 14.1 5.1 5.2 2.8 1.4 1.7 1.8 1.7 4.2 Gd157 246.9 48.6 85.0 109.9 38.6 190.3 26.2 32.6 155.4 121.9 51.9 41.5 127.3 65.8 82.4 116.5 112.5 175.6 Tb159 67.0 16.1 28.9 39.7 13.1 31.8 7.2 7.9 45.3 34.4 15.9 12.2 39.7 19.3 26.2 38.6 33.8 48.9 Dy163 637.7 179.5 322.9 472.1 146.0 270.2 71.7 80.0 427.8 352.4 174.3 129.8 407.5 196.4 269.1 384.2 335.2 428.0 Ho165 203.8 60.9 110.6 171.2 49.5 86.3 23.3 28.2 125.5 114.4 60.1 44.9 128.7 66.5 85.4 112.5 103.8 116.1 Er166 832.7 252.1 473.4 769.1 197.2 354.5 92.7 124.6 483.3 454.6 251.6 190.8 490.7 286.8 333.3 426.8 421.3 427.4 Tm169 180.3 55.2 106.8 178.6 40.7 78.9 18.8 29.3 103.8 103.4 58.3 44.5 97.5 67.9 72.4 90.3 93.2 88.6 Yb172 1724.1 540.9 1072.9 1806.7 372.5 811.1 175.4 310.0 997.9 1093.1 618.8 466.3 873.7 731.3 713.7 859.1 928.8 820.4 Lu175 275.4 79.9 153.5 281.4 51.7 123.2 31.1 49.2 141.5 145.1 89.0 71.8 129.7 110.4 98.2 122.6 139.3 109.0 Hf178 11509.5 10253.6 12036.6 14758.2 8118.5 11182.6 7726.1 10347.5 10222.8 8335.0 8711.6 10144.2 10833.8 11317.0 9524.5 11016.6 12726.1 13414.6 Pb208 65.9 21.9 67.8 46.2 10.0 115.2 2.5 10.6 33.5 93.8 45.5 50.7 13.6 40.1 25.7 27.1 43.6 72.8 Th232 768.9 84.8 371.7 607.9 150.3 1144.7 46.2 168.3 471.3 1738.9 826.6 888.8 252.7 578.8 389.8 400.2 590.7 622.5 U238 995.2 341.2 1424.9 2582.6 248.2 4743.5 54.4 452.0 991.6 1349.2 721.9 1067.3 683.0 1701.9 1287.8 1143.9 2006.1 1798.3
Age (Ma) 597.4 606.4 590.9 573.1 525.6 612.1 599.2 608.6 607.9 618.4 601.9 587.1 599.6 636.0 636.3 609.9 594.7 608.0 No. 12 4 7 3 14 15 19 11 12 2 3 2 5 11 8 12 6 11 Zircons Setting WPG WPG WPG WPG VAG VAG VAG VAG VAG VAG WPG/VAG
193 Table 5.1 (continued): A summary of zircon LA-ICPMS trace element data obtained from 18 dated magmatic suites across the Arabian Shield. All zircon analyses and corresponding CL images are displayed in Appendices 7 and 3 respectively. Values were processed using ‘Glitter’ software (Van Achterbergh et al., 2001) with procedural details described in Appendix a7. The symbol ‘MC’ designates the zircon morphological classes within a given suite. The Abbreviations ‘WPG’ and ‘VAG’ correspond with Within Plate Granite and Volcanic Arc Granite respectively (Chapter 4.4). The U-Pb age presented under the symbol ‘MC’ correlates to populations of zircons within the same suite containing the same morphology.
Ibn Subh Suite Najirah Granite [nr120] Wadbah Suite [wb65] Makkah Suite [dm01a] Jar-Salajah Complex [js202] Shufayyah Complex [su216] Hashbal Suite [ih68] MC1 MC2 MC3 MC1 MC2 MC3 MC1 MC2 MC3 MC1 MC2 MC3 MC1 MC2 MC3 [sf209] Na23 22.4 13.8 20.4 116.2 19.8 21.8 15.4 1384.6 1181.0 1447.0 193.8 177.2 81.8 79.5 101.2 101.6 144.7 Mg24 29.6 3.8 105.0 282.7 3.1 11.5 52.7 254.8 114.7 68.5 38.3 1067.4 135.2 31.7 99.4 212.9 32.7 Al27 147.9 38.3 534.5 927.8 11.5 128.3 107.5 324.8 300.7 140.6 310.3 1878.3 422.4 103.7 323.3 422.9 209.0 P31 353.6 320.9 489.1 615.6 264.7 583.4 165.7 2516.3 1501.9 2665.9 441.0 1202.2 438.9 523.1 443.9 512.0 542.4 K39 24.4 7.4 47.6 38.6 12.6 39.6 10.2 139.1 136.6 173.6 237.2 720.5 217.9 23.3 118.8 49.9 162.4 Ca43 556.9 366.6 737.2 1020.6 391.2 1477.3 166.1 9174.4 10244.1 9835.7 819.8 2225.4 426.4 813.2 738.5 1025.7 802.2 Ti49 20.3 9.9 21.9 31.8 11.2 17.6 11.6 51.3 31.2 33.5 16.8 268.2 189.9 13.1 42.2 147.6 60.9 Fe57 810.7 255.6 423.5 588.0 125.6 702.4 695.8 808.3 487.6 260.2 432.2 2412.9 683.8 207.6 628.1 721.4 387.2 Rb85 0.3 0.3 0.8 0.8 0.1 0.4 0.2 0.3 0.4 0.3 0.6 4.0 1.0 0.2 0.4 0.3 0.5 Sr88 2.4 0.8 4.1 10.4 0.3 1.0 0.5 0.3 1.0 0.2 0.9 8.3 1.1 1.4 1.6 4.5 1.0 Y89 3118.1 1450.9 2768.9 3747.7 1181.0 1362.8 1406.5 1787.4 1296.9 1118.7 3371.3 4675.2 1910.0 1771.8 2316.4 2488.4 3639.1 Zr90 524366.8 461574.7 473000.5 462633.3 519645.6 519405.2 518837.8 538473.3 503104.7 541074.5 500635.5 472419.5 518765.8 502629.4 521027.1 550320.3 519644.6 Nb93 24.7 2.6 12.0 23.2 3.8 4.2 4.6 2.1 1.7 1.5 2.0 5.0 2.3 1.6 1.4 3.3 2.6 La139 62.0 2.3 10.1 16.7 6.2 12.5 0.7 0.0 0.1 0.0 1.8 24.2 1.8 1.4 0.8 2.6 2.4 Ce140 189.0 12.5 50.8 122.9 30.8 46.1 22.6 35.3 27.6 23.3 12.4 168.3 18.5 22.8 21.8 81.6 16.5 Pr141 19.2 1.4 6.2 12.3 3.0 6.1 1.1 0.2 0.3 0.2 0.9 20.5 1.2 0.8 0.5 2.2 1.2 Nd146 115.7 12.6 39.9 77.2 20.9 40.6 12.5 4.0 3.8 3.2 9.7 131.9 8.4 6.4 5.3 17.2 11.5 Sm147 63.4 10.7 30.4 54.5 15.7 25.7 16.3 7.1 5.7 5.5 21.4 78.2 8.6 6.6 8.1 11.9 21.6 Eu153 4.3 0.9 2.2 6.4 1.8 9.2 3.9 3.7 2.9 2.8 13.5 6.1 0.9 1.2 1.4 1.7 9.3 Gd157 154.5 41.8 94.2 139.0 50.8 66.7 57.6 33.8 24.4 24.1 110.5 180.7 36.7 32.9 44.0 45.2 108.9 Tb159 43.4 13.9 30.7 44.1 14.5 18.5 16.7 12.0 8.7 8.5 36.5 50.8 13.5 12.0 16.2 16.3 36.5 Dy163 413.7 154.5 319.3 444.4 145.5 177.9 168.8 152.3 107.9 101.6 375.9 513.6 169.9 153.0 205.8 206.3 391.2 Ho165 123.6 53.5 102.0 138.0 46.2 53.7 54.3 60.8 43.5 39.2 123.9 166.9 67.0 60.2 81.0 82.9 133.8 Er166 442.0 217.6 395.4 532.2 175.0 199.1 206.6 293.1 214.2 185.7 501.8 675.0 307.8 277.7 366.8 391.1 549.1 Tm169 79.9 44.9 78.6 106.3 35.9 40.1 42.2 75.9 56.9 48.1 102.9 138.3 70.3 64.0 82.1 89.3 113.4 Yb172 648.2 420.5 699.9 954.0 338.1 373.4 391.8 900.2 684.9 571.6 959.1 1272.7 700.6 649.9 796.7 887.8 1045.2 Lu175 93.4 65.6 105.4 144.2 49.3 55.4 57.4 151.6 116.6 95.5 158.6 219.3 126.3 112.5 143.8 167.1 174.5 Hf178 7528.1 9802.8 10496.1 11715.1 9062.9 8597.5 9948.9 7271.2 7078.0 8324.4 8532.6 9382.0 10183.6 9223.7 10069.0 11016.6 9173.1 Pb208 13.6 2.5 9.9 16.3 2.3 19.2 4.9 18.7 13.0 11.1 5.4 13.6 4.7 4.6 9.3 10.8 6.4 Th232 237.7 44.7 114.9 173.9 39.8 46.4 57.3 233.2 163.1 142.7 71.8 323.3 77.7 68.3 131.3 233.5 99.6 U238 696.2 147.0 484.0 897.6 160.9 169.8 237.8 277.9 200.2 166.1 212.3 520.1 230.5 212.9 282.3 614.5 266.0
Age (Ma) 617.6 631.4 606.5 585.4 629.8 614.0 601.1 867.6 847.0 829.2 710.0 693.2 676.3 730.9 716.7 696.3 698.7 No. 15 4 11 9 4 8 4 4 8 5 6 4 9 4 7 4 10 Zircons Setting VAG WPG WPG/VAG VAG VAG VAG VAG
194 Chapter 6: Discrete Crystallisation Ages within Granitoid Zircon Populations.
6.1 Introduction.
U-Pb zircon geochronology is a widely accepted and utilised method for constraining the crystallisation age and metamorphic events within a given suite. Regardless of the igneous, sedimentary or metamorphic origin, zircon fractions within the same sample can define a single concordant age or a linear trend of discordance with upper and lower intercepts. These are usually interpreted as the crystallisation and inherited components respectively. Focusing on granitic samples, Paterson et al. (1992) and Williams (1992) outlined that discordant granitic analyses can have multiple inherited ages. It is claimed that granitoids contain mixed inheritance based on 1) melting of heterogeneous age crust, and 2) incorporation of multiple zircon populations.
By contrast, granitic concordancy yielding a tight crystallisation age (inheritance absent) appears to be a textbook open and shut case. Numerous studies consist of a dozen or so (sometimes as little as 5) analysed primary oscillatory zoned zircons, which are thought to convincingly constrain a granitoid age. In some cases, this may be true, however, circumstances of limited zircon populations and/or statistically insufficient data sets places doubt on drawn conclusions. This begs the question can multiple zircon morphologies found within a sample produce multiple crystallisation ages.
One acknowledges that distinct zircon populations are a common occurrence in syncollisional granitoids. These frequently display predominant crystallisation ages constrained by primary zircons and are often accompanied by recrystallised grains interpreted to form metamorphic events. Discounting inherited Pb in zircons or machine bias, it would be assumed that multiple crystallisation ages would be non-existent in undeformed post-tectonic granitoids. If no apparent incorporation of zircons from surrounding crustal sources is present, any morphological differences in zircon grains would solely be a product of changing physical constraints inside the magma chamber. Theoretically, the changing heat and pressure would produce different zircon morphologies, but any age difference should be negligible. And yet, a similar study was
195 conducted by Schaltegger et al. (2002) in the Kohistan Island Arc Complex, Pakistan in which multiple crystallisation ages and a changing mantle source within a given suite were interpreted as the result of magmatic pulsing (Chapter 7.3).
This chapter aims to illustrate that the differing zircon morphology classes (MC) identified within a given sample allow multiple discrete crystallization ages to be distinguished that are not products of inheritance or metamorphism. The geological age scatter possessed by the zircon morphologies also produces non-Gaussian distributions in not only the syncollisional units, but more significantly, undeformed post-tectonic suites. Conventional age separation techniques using Ludwig (2000) Isoplot software reveal two discrete ages are illustrated by these samples, but a third group is obtainable using a non-linearised approach.
6.2 Identification of Distinguished Zircon Morphologies.
As described in Chapter 3, distinct zircon morphologies were differentiated by CL imagery within the 900-636Ma syncollisional Makkah Suite, Shufayyah Complex and Jar-Salajah Complex and 636-600Ma post-orogenic Kawr Suite, Najirah Granite and Wadbah Suite. These suites contained a mixture of stubby well zoned, stubby poorly zoned, elongate well zoned and elongate poorly zoned morphologies that were divided into three groups designated as morphology class 1, 2 and 3 (Figure 6.1 and Appendix 3).
The distinguished zircons were then ablated for Hf isotopes (Chapter 3.3) and REE (Chapter 5) to indentify possible mantle source discriminators between neighbouring suites. As summarised in Figure 6.1, the discrete zircon morphologies are compared with trace element abundances and illustrate interesting trends worth highlighting. These REE analysed zircons are compared with their respective U-Pb age and appear to show geological age scatter consistent with the 3 distinct morphology classes. It should be noted that the X-axis zircon age is independent of the Y-axis element concentration, which exhibits scatter possibly due to element fractionation and element partition coefficients in the melt.
196 Figure 6.1 part 1: A representation of the 3 different zircon morphologies found in the syncollisional intrusive samples from the Makkah Suite (Black) and Shufayyah Complex (Red). The identified zircon morphologies are compared with Hf and HREE concentrations and the resulting geological age scatter appears to correlate with 3 distinguished age groups. Morphology class 1, 2 and 3 correlate with the numbers 1, 2, and 3 alongside the representative zircon morphologies. Note that the Y-axis element concentration shows variation (possibly a product of fractionation and element partition coefficient parameters in the melt), but the X-axis age is constant and independent of the Y-axis element. The U-Pb, zircon morphology and Hf isotope analysis is described in Chapter 3 and displayed in Appendices 2, 3 and 4 respectively. The REE analysis is described in Chapter 5 and presented in Appendix 7.
197 Figure 6.1 part 2: A representation of the 3 different zircon morphologies found in the granitic samples from syncollisional Jar-Salajah Complex (Black) and post-orogenic Najirah Granite (Red). The identified zircon morphologies are compared with Hf and HREE concentrations and the resulting geological age scatter appears to correlate with 3 distinguished age groups. Morphology class 1, 2 and 3 correlate with the numbers 1, 2, and 3 alongside the representative zircon morphologies. Note that the Y-axis element concentration shows variation (possibly a product of fractionation and element partition coefficient parameters in the melt), but the X-axis age is constant and independent of the Y-axis element. The U-Pb, zircon morphology and Hf isotope analysis is described in Chapter 3 and displayed in Appendices 2, 3 and 4 respectively. The REE analysis is described in Chapter 5 and presented in Appendix 7.
198 Figure 6.1 part 3: A representation of the 3 different zircon morphologies found in the post-orogenic granitic samples from the Kawr Suite (Black) and Wadbah Suite (Red). The identified zircon morphologies are compared with Hf and HREE concentrations and the resulting geological age scatter appears to correlate with 3 distinguished age groups. Morphology class 1, 2 and 3 correlate with the numbers 1, 2, and 3 alongside the representative zircon morphologies. Note that the Y-axis element concentration shows variation (possibly a product of fractionation and element partition coefficient parameters in the melt), but the X-axis age is constant and independent of the Y-axis element. The U-Pb, zircon morphology and Hf isotope analysis is described in Chapter 3 and displayed in Appendices 2, 3 and 4 respectively. The REE analysis is described in Chapter 5 and presented in Appendix 7.
199 6.3 Identification of Non-Gaussian Probability Distributions.
As outlined in the previous section, the identification of 3 distinguished zircon morphologies within granitic samples appears to produce geological age scatter suggesting 3 age groups. This grouping warrants further investigation using statistical means to establish that the separation of 3 zircon morphologies correlates with discrete age groups.
Conventional U-Pb geochronology of primary magmatic zircons ideally provides tightly constrained crystallisation ages and Gaussian distributions (Figure 6.2 part 1). Typically, undeformed granitoids require 10-12 data points to convincingly determine its crystallisation age and even when this is increased to ~20 analyses, this still yields sharp normal Gaussian distributions (Figure 6.2 part 1). However, the samples that contain 3 zircon morphologies contain 3-4 times the normal amount of data as typical undeformed intrusives and interestingly, reveal broad, skewed and multi- peaked probability curves that are non-Gaussian distributions. Many samples analysed in this study contain similar amounts of analysed data points (e.g. Admar, Al Bad, Ibn Hashbal and Subh Suites), but produce tightly constrained crystallisation ages defined by similar zircon morphologies, hence separation is not warranted or possible. However, syncollisional (Makkah, Shufayyah Jar-Salajah Complexes) and undeformed post-tectonic suites (Kawr, Najirah and Wadbah) warrant further investigation of obvious non-Gaussian probability distributions (Figure 6.2 part 1).
A validation of the normal component of a Gaussian distribution can be gauged by its MSWD value. Figure 6.2 part 2 illustrates that the sharp peaked, normal Gaussian distributions contain values of ~1, meaning they fit a normal distribution. It also should be pointed out that the samples with multiple morphology groups and non- Gaussian distributions contain values >1. These are 1.6 (Makkah Suite), 1.2 (Shufayyah Complex), 3.6 (Jar-Salajah Complex), 2.4 (Kawr Suite), 2.9 (Najirah Granite) and 2 (Wadbah Suite) and are vastly different from 0.21 (Subh Suite) and 0.76 (Ibn Hashbal Suite) of the sharp peaked normal distributions. Overall, this suggests that 4 of 6 samples contain large MSWD values and more than one age is suspected.
200 Figure 6.2 part 1: Probability distribution plots of 3 syncollisional and 3 post-tectonic granitoids sampled in the Arabian Shield. Note the large distribution range, skewed and multi- peaked nature of the probability curves. The bottom two images are comparative peaks: syncollisional (left) and post-tectonic (right). These are tightly constrained intrusives with a sharp peak and represent ‘ideal’ single age events. Samples js, kw and nr contain non-Gaussian bimodal distributions, whilst sample su exhibits a skewed asymmetric non-Gaussian distribution. Samples dm and wb are less obvious, but like the others, still contain 3 zircon morphologies. Raw isotope age data was processed using Glitter software (Van Achterbergh et al., 2001) and conveyed using the Isoplot macro (Ludwig, 2000).
201 Figure 6.2 part 2: Weighted average plots of 3 syncollisional and 3 post-tectonic granitoids correlating with Figure 6.2 part 1. A normal Gaussian distribution contains a spread of data in which the MSWD value is ~1. This is seen in the bottom two images of Figure 6.2 part 1 which are tightly constrained normal Gaussian distributions. However, the large MSWD values for the samples js, kw, nr and wb are >1 and suggest that these are non-Gaussian distributions with more than 1 mean age as reflected in their non-Gaussian probability plots in Figure 6.2 part 1. Samples dm and su are less obvious, but like the others, still contain 3 zircon morphologies. Sample su also contains a skewed asymmetric non-Gaussian distribution as illustrated in Figure 6.2 part 1. Raw isotope age data was processed using Glitter software (Van Achterbergh et al., 2001) and conveyed using the Isoplot macro (Ludwig, 2000).
202 6.4 Discrete Ages Using Isoplot Software.
To investigate whether separate ages can be identified for the multi zircon morphology populations and corresponding non-Gaussian distributions, the well established method called Isoplot age unmix (Ludwig, 2000) has been applied. This involves fitting a Gaussian distribution curve to all the data for a given sample irrespective of the morphology type with the width governed by the individual ages and assigned errors of a particular sample. Figure 6.3 is separated into two parts: 1) Isoplot age unmix which fits a Gaussian function. 2) Isoplot linearised probability plot which involves placement of a line of best fit through the data to gauge a normal Gaussian distribution fit.
Both schemes utilise weighted average 206Pb-238U ages and yield similar results. The data are convincingly separated into 2 discrete age populations using the ‘age unmix’ macro. This validates that the non-Gaussian probability distributions can be separated. Two groups are also portrayed in the ‘linearised probability’ macro (Figure 6.3). There are distinct age gaps between data groups indentified in the probability diagrams. These sometimes illustrate a tendency to migrate horizontally away from the line of best fit, thus suggesting a discontinuous, non-normal distribution of zircon ages i.e. the sample contains more than one mean age. Groups designated as ‘X’ are discussed further in Chapter 6.5. Overall, the 6 samples exhibit a minimum of two age groups, which is most significant for the undeformed post-tectonic suites. The tectonic implications are discussed further in Chapter 8.
Gaussian distribution curves are the most common form and utilised statistical distribution functions. Data within the bell shaped curve is divided into ~33% intervals (+1σ and -1σ) either side of the median. However, if data within the bell shape curve is multi-modal (Figure 6.3) determining distributions is less obvious. There are frequently values on the tail ends of the curve that are grouped together, which questions the assumptions of the double infinite span of a Gaussian distribution (i.e. no zircon data will ever read ‘0Ma’ nor the maximum age of the earth). It is possible that this zircon data, although producing a minimum of two ages (Ludwig, 2000), is not best suited for analysis as Gaussian distribution, but rather a function with finite intervals.
203 Zircon data in the thesis is also subjected to linearised distribution plots (Figure 6.3) to test the normal Gaussian component of the distribution. Gaussian distributions on linearised logarithmic plots are represented as straight lines through data groups i.e. the greater the slope through a cluster data, the larger the standard deviation and the more non-normal the distribution. Once again a minimum of two age groups is distinguished, but there appears to be convenient breaks in the data with a non-normal spread, which is suggestive of a third group designated as ‘X’. One limitation of this method is fitting a linear function through a cluster of data. If data points are randomly distributed, linearising it may give inadequate results, which is often skewed on logarithmic scales. Overall, the 6 samples show a minimum of two zircon populations defined by non-normal distributions.
6.5 Establishment of Three Discrete Zircon Ages.
As outlined in the previous section, a minimum of two age groups was recognised using the Isoplot software (Ludwig, 2000). This confirms the separation of non-Gaussian distribution curves. However, there appears to be a third group designated as ‘X’ (Figure 6.3) that is unable to be extracted without significant error overlap between other groups. This is attributed to sample data automatically fitted with a Gaussian curve and linear fit respectively. This section aims to extract the third age group, which corresponds with 3 zircon morphologies identified within a sample
The above methods show convincingly that a minimum of two groups are distinguished, thus supporting the separation of multi-modal (non-Gaussian) zircon distributions in this data set. As illustrated in Figure 6.4, U-Pb concordia diagrams can separate these into 3 discrete ages expressed as individual non-overlapping age groups. Although this adequately highlights the possibility of 3 groups, it still involves fitting a line of intercept through error ellipses.
One possible method to overcome this illustrated in the lower part of Figure 6.4 is to use weighted average 206Pb-238U ages of all raw data and establish a mean age. This discounts the use of fitting functions of any kind and purely establishes a mean value based on the given ages (i.e. total sum of age data divided by the number of data
204 points). Discrete age groups are established based on the data error from the mean. Data values that are between -1σ and +1σ form
Figure 6.3 part 1: Probability distribution plots of 3 syncollisional intrusives sampled in the Arabian Shield. Raw isotope age data was processed using Glitter software (Van Achterbergh et al., 2001) and conveyed using the Isoplot macro (Ludwig, 2000). The non-Gaussian probability distributions have been analysed with Isoplot age unmix (left) and linearised probability plot (right) software (Ludwig, 2000). This confirms that a minimum of two age populations are recognized, thus confirming a non-Gaussian distribution. However, there appears to be a third population designated as ‘X’, but is not recognised using this macro. The extraction of this third population is described in Chapter 6.5. Note these U-Pb age population groups are independent of the zircon morphology classes described in previous sections.
205 Figure 6.3 part 2: Probability distribution plots of 3 post-tectonic granitoids sampled in the Arabian Shield. Raw isotope age data was processed using Glitter software (Van Achterbergh et al., 2001) and conveyed using the Isoplot macro (Ludwig, 2000). The non-Gaussian probability distributions have been analysed with ‘Isoplot age unmix’ (left) and ‘linearised probability plot’ (right) software (Ludwig, 2000). This confirms that a minimum of two age populations are recognized, thus confirming a non-Gaussian distribution However, there appears to be a third age population designated as ‘X’, but is not recognised using this macro. The extraction of this third population is described in Chapter 6.5. Note these U-Pb age population groups are independent of the zircon morphology classes described in previous sections. the majority of zircon analyses and represent typical Gaussian style discrimination (Group 2). The two extreme ends are >+1σ and <-1σ (Groups 1 and 3 respectively) and form the two remaining discrete groups. One might expect a zircon distribution to
206 contain a tight crystallisation age with some extreme endmembers. However, many samples contain a somewhat even distribution of data points spread across 3 age groups that correlate with the geological age scatter of the 3 different zircon morphologies. This suggests that the age groups are not isolated extreme endmembers, but rather a collection of zircon analyses forming a discrete age that reflect the zircon morphology.
Using the Shufayyah Complex as an example of a broad non-Gaussian distribution (Figure 6.4), 47 individual grains were analysed. The weighted average method continued here reveal 3 individual 206Pb-238U ages: 730.9±9.2Ma (n=9), 716.4±4Ma (n=29) and 695.3±7.5Ma (n=9). The grains are within ±10% from 100% concordancy, show no obvious metamorphic characteristics and are separated into 3 close, nevertheless distinct groups (remembering a minimum of 2 is recognised from Ludwig, 2000). This method was also applied to the multi-modal plots such as the post- tectonic Najirah Granite (Figure 6.4). These grains exhibit 3 individual 206Pb-238U ages: 631.4±9.1 (n=5), 606.5±6 (n=9) and 585.4±8.8 (n=6). All raw data for discrete age groups, including error from the mean, is displayed in Appendix 2.
6.6 Relationships between Machine Error and Age separation.
Ablation drift is a well documented occurrence during U-Pb analysis (Jackson et al., 2004) and must be taken into consideration. This is also corrected using GJ standards, but to completely eliminate it as a potential threat to age separation, it must be addressed. Using the Shufayyah Complex as an example (contains 3 distinct zircon morphologies and greatest number of analyses) the maximum drift within a given procedural block (repetition known as ‘block’ consisted of 3 GJ, 2 Plesovice, 10-12 unknowns and finally 2 GJ values with the standard GJ values used to linear fit the unknown values) is calculated (Figure 6.5).
Group 2 (<1σ->-1σ) contains the greatest number of data points, thus provides the ideal candidate to calculate a slope. A linear fit was established by using standard linear Y=mx+c modelling (Microsoft Excel) and divided against the difference between
207 Figure 6.4 part1: These syncollisional intrusives have been divided into 3 discrete age groups correlating with 3 zircon morphologies: Top) U-Pb concordia diagrams illustrate the separation of a widespread crystallisation event into 3 non-overlapping groups. Bottom) Weighted average distribution plots of the same zircon data plotted by zircon morphology classes without linear fitting, which more accurately constrains the 3 separated crystallisation ages. Analyses have been numerically arranged in descending order to highlight the maximum and minimum values. These are originally randomly distributed analyses unrelated to machine bias (Figure 6.5). Age groups are based on error from the mean age (Chapter 6.5). The tectonic significance of these discrete age groups is discussed in Chapter 8. Raw isotope age data was processed using Glitter software (Van Achterbergh et al., 2001) and conveyed using the Isoplot macro (Ludwig, 2000).
208 Figure 6.4 part2: These post-tectonic suites have been divided into 3 discrete age groups correlating with 3 zircon morphologies: Top) U-Pb concordia diagrams illustrate the separation of a widespread crystallisation event into 3 non-overlapping groups. Bottom) Weighted average distribution plots of the same zircon data plotted by zircon morphology classes without linear fitting, which more accurately constrains the 3 separated crystallisation ages. Analyses have been numerically arranged in descending order to highlight the maximum and minimum values. These are originally randomly distributed analyses unrelated to machine bias (Figure 6.5). Age groups are based on error from the mean age (Chapter 6.5). The tectonic significance of these discrete age groups is discussed in Chapter 8. Raw isotope age data was processed using Glitter software (Van Achterbergh et al., 2001) and conveyed using the Isoplot macro (Ludwig, 2000).
209 the overall maximum and minimum values within a given block. This yielded a maximum possible machine drift value of ~5-10%, thus any drift outside of Group 2 is negligible. This alongside positive and negative varying gradients (would expect all the same if drift occurred) suggests that ablation drift is not a significant factor, thus supporting the presence of 3 distinct age groups correlating with 3 zircon morphologies.
The spread of the Shufayyah Complex data reveals a mean of 715.4±3.6Ma with a maximum and minimum age of 732.7Ma and 687.3Ma respectively (Figure 6.5). The data in sequential experimental time shows a random distribution of ages spread across 4 data blocks. Visually, it is clear and expected that most data points (n=29 of 47) are constrained (-1σ - +1σ) to the mean value (n=47). These are highlighted as Group 2 values. However, there are also 18 of 47 data points that define Group 1 (>1σ from mean) and Group 3 (<-1σ from mean). The extreme groups are not confined to one data block, but are evenly spread over the 4 data blocks (Figure 6.5). The recalibration of the machine after every procedural data block also suggests that fractionation is not an issue. This eliminates the possibility of machine malfunction within a given block.
Another possibility related to 206Pb-238U discrete age groups is fluctuations in concordancy and isotope ratios. One might expect the highest and lowest values to correspond with the extreme groups conveying skewed distribution values. This would certainly place doubt on the validity of separating discrete ages. However, Figure 6.6 highlights negligible correlation between concordancy and 207Pb-206Pb, 207Pb-235U and 208Pb-232Th parameters with discrete ages. These illustrate a random distribution, thus eliminating machine bias.
210 Figure 6.5: Weighted 206Pb/238U age distribution plots divided according to morphology class and corresponding with zircon analyses in sequential experimental time. The analyses are placed into procedural blocks (n=number of analyses) separated by the LAICPMS recalibration using the recognised standard GJ. This figure aims to highlight the random distribution of age values and confirm that no discrete age group correlates with any specific procedural block, thus suggesting no experimental error. Maximum drift slopes designated as dashed lines within Group 2 data (Makkah and Shufayyah samples) contain varying positive and negatives slope and as described in Chapter 6.6, ablation drift is not a significant factor. The maximum and minimum age values are randomly spread throughout the data and correlate with the numerically arranged values in Figure 6.4. Raw isotope age data was processed using Glitter software (Van Achterbergh et al., 2001) and conveyed using the Isoplot macro (Ludwig, 2000).
211 Figure 6.6 part1: Top) Syncollisional weighted 206Pb/238U age distribution plots divided according to morphology class vs. concordance of Group 1 (>1σ), Group 2 (<1σ->-1σ) and Group 3 (<-1σ) discrete zircon ages (Chapter 6.4). Note the random distribution of concordance that conveys no bias towards any one group. Data shows overlap between groups, thus no correlation of discordance and discrete ages. Bottom) The same discrete age groups (designated as G1, G2 and G3) plotted as black (206Pb/238U), Red (207Pb/235U), green (208Pb/232Th) and blue (207Pb/206Pb) isotope age values. Note the random distribution of isotope values within a given group which show an even distribution of low and high ages i.e. significant overlap between each group. This confirms that the discrete ages are not a product of extreme Th or Pb loss values, hence validates the separation into 3 distinct groups. Raw isotope age data was processed using Glitter software (Van Achterbergh et al., 2001) and conveyed using the Isoplot macro (Ludwig, 2000).
212 Figure 6.6 part2: Top) Post-tectonic weighted 206Pb/238U age distribution plots divided according to morphology class vs. concordance of Group 1 (>1σ), Group 2 (<1σ->-1σ) and Group 3 (<-1σ) discrete zircon ages (Chapter 6.4). Note the random distribution of concordance that conveys no bias towards any one group. Data shows overlap between groups, thus no correlation of discordance and discrete ages. Bottom) The same discrete age groups (designated as G1, G2 and G3) plotted as black (206Pb/238U), Red (207Pb/235U), green (208Pb/232Th) and blue (207Pb/206Pb) isotope age values. Note the random distribution of isotope values within a given group which show an even distribution of low and high ages i.e. significant overlap between each group. This confirms that the discrete ages are not a product of extreme Th or Pb loss values, hence validates the separation into 3 distinct groups. Raw isotope age data was processed using Glitter software (Van Achterbergh et al., 2001) and conveyed using the Isoplot macro (Ludwig, 2000).
213 6.7 Additional Evidence for Discrete Ages and Discussion.
The identification of 3 of different zircon morphologies within granitic samples produced geological age scatter consistent with non-Gaussian distributions and large MSWD values. Using conventional Isoplot software (Ludwig, 2000), a minimum of two age groups is recognisable, but a third group extraction is also possible utilising a non- linearised approach. Even if one does not agree with the discrete age separation, differences between zircon morphology and geochemistry are undeniable.
Prior to any interpretation, it is important to highlight the complex mingling field relationships observed in both IA+Syn (Makkah Suite) and NHSG (Kawr Suite) intrusions. The former ranges from gabbros to granodiorites (Chapter 2.3.1), whilst the latter from gabbros to aegirine-bearing alkali-granites (Chapter 2.3.3). It would therefore be unsurprising if the samples reveal not only different geochemical parameters, but also discrete zircon populations. Interestingly, the Kawr and Najirah perthitic suites intrude orogenic sutures and can be separated into discrete age populations. This is discussed further in Chapter 8.
As described here and in Chapter 3.2, the plutons in question contain multiple differentiated zircon morphologies. It was found that the separation of discrete age groups actually correlates remarkably well with differentiated morphologies (Appendix 3). The oldest groups correspond with stubby prisms often lacking oscillatory zoning. Youngest groups are often elongate ‘needle like’ prismatic shapes possessing finely laminated oscillatory zoning. In general, there is a consensus for the oldest groups to convey lower temperature zircon types (~600-7000C), whilst younger zircons with higher temperature morphologies (~700-8000C).
Rare Earth Element geochemistry performed on discrete zircon groups constrains further the independent nature of each morphological group (Chapter 5), thus supporting the validity of age separation. Hafnium isotopic analysis confirms the juvenility of each group suggesting a homogeneous juvenile mantle system (Chapter 3.3). The combination of geochronological and geochemical parameters helps convey the idea of long lived magmatism pulsing (MASH zones) underneath orogenic belts. This is discussed further in Chapter 7.3.
214 Given the evidence described here that different zircon morphologies correlate with multi-modal distributions and reflect discrete ages, these is still the possibility that the age differences are a function of inheritance or metamorphic events. However, this possibility is deemed unlikely for the following reasons:
1) The age of any country rock surrounding the intrusions is commonly >50Myrs older. If inheritance occurs, this would be reflected in the U-Pb concordia with large age gaps between zircon groups. As illustrated in Figure 6.4, the crystallisation ages are <20Myrs apart and show an initial ‘single’ crystallisation age that can be divided into small populations that correlate with the geological age scatter of the zircon morphologies.
2) Post-tectonic granitoids are aegirine-bearing alkali-granites and represent undeformed magmatism. These contain primary oscillatory zoned unaltered zircons with no age distinction between cores and rims, but vary in morphology (Chapter 3.2). This coupled with the absence of lead loss or discordance (Figure 6.6) places doubt on metamorphism or resetting of any kind.
3) Syncollisional suites could be the result of metamorphism, but exhibit no age difference between cores and rims or significant recrystallisation. It is suggested that these are unaltered primary zircons.
4) Syncollisional samples also appear as a single crystallisation age, but are subdivided in <20Myr groups (Figure 6.4) that correlate with the geological age scatter of the zircon morphologies. These display no inherited ages or lead loss/discordance (Figure 6.6) commonly associated with metamorphism.
5) Even if one places doubt on multiple crystallisation events within a sample and suggests that metamorphism is a factor, this still constrains 3 discrete events with tectonic implications related to subduction (Chapter 8).
Overall, it is suggested that these samples are divided into 3 discrete crystallisation ages. The tectonic significance is discussed in Chapters 7 and 8.
215 Chapter 7: Arabian Shield Post-Orogenic and Anorogenic Granitoids; Petrogenetic Mechanisms for Distinct Contaminated and Enriched Mantle Sources.
7.1 Introduction.
The term A-type or anorogenic granite was first introduced by Loiselle and
Wones (1979) for a distinct group of granitoids low in CaO and Al2O3, but more importantly, high in total alkalis (K2O-Na2O), FeO/FeO+MgO and REE (Zr, Nb, Ta). It was proposed that these were the derivatives of alkali basalt fractionation with minimal crustal interaction. These are typically found at the termination of orogenic cycles, hence are post-orogenic, and represent anorogenic extension magmatism derived from enriched mantle sources. As outlined by Eby (1990), these granites contain geochemical and isotopic parameters indicative of limited to moderate crust-mantle interaction. However, the combination of lithospheric mantle and overlying crust that generates such A-type diversity (Chapter 1.3) is a highly debated topic (Bonin, 2007; Frost and Frost, 2011).
Mantle sources beneath the Arabian Shield generate A-type granites that are arguably derived from isotopically juvenile enriched or depleted mantle (Stein and Goldstein, 1996; Stoeser and Frost, 2006; Be’eri-Shlevin et al., 2010). However, it is well established that within these juvenile terranes, crustal growth has had little time to become isotopically distinguished from its original mantle source. Any contamination of mantle sources would be isotopically distinguishable and suggest that not all post- orogenic granitoids are derived from enriched mantle sources with limited crust-mantle interaction.
This chapter aims to illustrate with petrological (Chapter 2), geochronological (Chapter 3.2) and geochemical (Chapter 4 and 5) data gathered in this study, that post- orogenic magmatism immediately followed lithospheric orogenesis and was derived from both enriched and depleted mantle sources. The identification of both contaminated (post-orogenic, 636-600Ma) and enriched (anorogenic, <600Ma) mantle, provides new insights into the respective tectonic roles following supercontinental assembly.
216 7.2 Geochemical Characteristics of Contaminated Granitoids.
As outlined in Chapter 4.4.4b, the classification of contaminated and enriched granitoids is not limited to post-tectonic suites, but also incorporates syncollisional and crustal magmatism. It is well established through geochronological data (Chapter 3.2) that the Arabian Shield contains older suites (730-636Ma) synchronous with terrane accretion. These sampled units are confined to the western Hijaz and Jiddah terranes (Figure 7.1) and are possibly linked to the break up and formation of the Rodinian and Gondwana supercontinents respectively (Chapter 8.6). These suture related ferromagnesian plutons form the initial oceanic crust generated in subduction style processes. Similarly, the generation of some post-tectonic suites such as the NHSG (Nabitah) intrusions involve the interaction of oceanic (west) and continental (east) fragments (Figure 7.1). It is therefore important to establish their geochemical relationship with the older IA+Syn samples, which are discussed first.
IA+Syn plutons, including the Makkah Suite, Jar-Salajah and Shufayyah Complexes and the Subh Suite volcanics are amongst the least evolved suites of all granitoids sampled in the Arabian Shield. These are dominated by plagioclase and ferromagnesian assemblages (Chapter 2) and unsurprisingly, contain amongst the highest FeO, CaO, MgO and lowest silica concentrations of any granitoid sampled (Chapter 4.2.1). This provides a relatively effortless task to discriminate these from post-tectonic/anorogenic suites by sampling using major elements (Figures 4.1-4.3). Most importantly, these illustrate a close affinity with N-MORB. They are also easily separated when utilising incompatible elements such as Nb, Y, Zr and Ga because of their low abundances. These exhibit linear fractionation trends from their parent N- MORB like mantle (Figure 4.3). Syncollisional suites are easily confined to the magnesian, VAG and I-type fields and are associated with calcic magmatism (Figures 4.12 and 4.14). The mafic endmembers are defined as depleted N-MORB like units (Figure 4.15).
REE patterns indicate a strong depletion in Nb and Eu and a slight enrichment in LREE synonymous with contaminated arc signatures (Figures 4.4 and 4.5). IA+Syn Nd isotopic signatures are the most juvenile of any granitoid and provide a convenient MORB like field (Figures 4.6-4.8). This is strongly associated with N- MORB and,
217 Figure 7.1: A summary map of the geochemical characteristic of granitic suites sampled in the Arabian Shield. The tectonic setting and ferroan/magnesian parameters were established using classification schemes from Pearce et al. (1984a) and Frost et al. (2001) respectively. These are described in detail in Chapter 4.4. Note the wide range in A-type granites correlating with both suture and within plate related environments, hence they potentially contain different mantle sources. Plutons such as the Kawr Suite are exceptional examples of a transition from VAG + magnesian to WPG + ferroan units within the same felsic endmembers. These provide a clear focal point to compare with classic style WPG ferroan alkali-granites such as the Abanat Suite. Sections A, B and C in the map correspond with Figures 7.2, 7.3 and 7.4 respectively which summarise the geochemical parameters and tectonic settings.. Note the blue ferroan alkali- granites correlate to the Idah Suite (classified as VAG), which are distinguished from the red ferroan alkali-granites of the younger Abanat suite (classified as WPG).
218 along with all contaminated plutons, is clearly separated from enriched AAPG suites (Figure 4.7). However, the oldest unit (Makkah Suite) shares a strong isotope affinity with the NHSG mafics and is emplaced into the isotopic Khida terrane field (Figure 4.7). This would suggest that the Makkah suite, like the NHSG mafics, is derived from N-MORB like mantle that was contaminated by the Paleoproterozoic Khida terrane. The zircon geochemistry is also distinctive showing an N-MORB like fractionation trend that continues on to produce VAG classified granitoids (Figures 5.1-5.6). Overall, and most importantly, the geochemistry of syncollisional suites is indicative of contamination and fractionation of an N-MORB source. The tectonic significance is discussed further in Chapter 7.3.
Following on from IA+Syn suites is the appearance of post-orogenic perthitic granitoids. These intrude or are juxtaposed to major suture zones and are divided into two groups: NHSG intrusions such as the Najirah Granite, Al Hafoor, Kawr, Ibn Hashbal and Wadbah Suites; and the POPG Admar, Al Khushaymiyah, Haml and Idah Suites. For the purposes of this discussion, the focus will be placed on the NHSG intrusions because of their large sample size and geochemical trends. However, the POPG suites are thought to be a product of a similar contamination processes (similar geochemical trends) and are discussed further in Chapter 7.3.
NHSG suites involve the collision of the western oceanic and eastern continental plates (Nabitah Belt) and as recently suggested by Flowerdew et al. (2013), are generated by a tear in the subducting slab In this section, the NHSG intrusions analysed in this report will be discussed. The Kawr and Al Hafoor Suites show mingling textures ranging from gabbroic mafics to perthitic granites (Kawr Suite aegirine-bearing, Chapter 2.3.3). These mafics are classified as MORB and IAT units (Figure 4.15) and are geochemically rich in FeO, CaO, MgO and low in silica concentrations and show strong fractionation patterns from N-MORB like affinities to intermediate and highly evolved perthitic endmembers (Figures 4.1-4.3). Kawr Suite alkali-granites are not easily distinguished from enriched AAPG suites using major element geochemistry. Surprisingly, these also contain similar trace element abundances, but using incompatible elements such as Nb, Y, Zr and Ga, these are easily distinguished from AAPG suites. These display strong linear fractionation trends from an N-MORB like source and incorporate all POPG units and older IA+Syn suites (Figure 4.3).
219 NHSG mafic REE patterns show strong depletion in Nb and Eu and a slight enrichment in LREE synonymous with a contaminated arc like signature (Figure 4.4). The NHSG granitoids mimic this contaminated behaviour which is not observed in the enriched mantle AAPG suites (Figure 4.5). The most notable difference between these granitoids and older IA+Syn/younger POPG units is the relatively higher HREE abundance. This is attributed to the involvement of continental crust that is absent in the western Shield. NHSG N-MORB mafics exhibit LREE enrichment patterns synonymous with contamination (U, Th, La, Le, Pb and Pr anomalies, Figure 4.5). This is suggestive of lower continental lithosphere melting and/or subducting plate involvement (geochemically distinguished from enriched mantle AAPG suites). These melts continue to fractionate towards perthitic endmembers e.g. Al Hafoor Suite, but are interrupted with a change in mantle chemistry with the production of the ferroan Ibn Hashbal and Wadbah Suites. This also occurs within the Kawr Suite as noted in the wholerock and zircon geochemistry and is discussed further in Chapter 7.3.
Most importantly, NHSG mafic isotopic signatures are clearly different to those of POPG and AAPG suites (Figure 4.6-4.8). These have a strong affinity with both the Khida terrane and N-MORB fields and are the least juvenile of sampled granitic suites. These mafics fractionate towards two endmembers: Al Hafoor perthitic alkali-granites (below the juvenile AAPG field); and Kawr Suite aegirine perthitic alkali-granites (within the juvenile AAPG field). The latter coincide with the initiation of younger ferroan NHSG suites. However, these are all distinguished from AAPG suites with Nb and suggestive of a contaminated N-MORB source. Although POPG syenites are initially more juvenile than NHSG mafics, they display a similar N-MORB affinity that fractionate to similar products. Zircon geochemistry is also distinctive, showing an N- MORB like fractionation trend initiating at POPG units and continues to produce the Al Hafoor and Kawr Suite perthitic units (Figures 5.1-5.6). However, there is a distinct transition within the Kawr Suite and, together with younger Ibn Hashbal and Wadbah Suites, discretely overlaps into the enriched zone defined by the AAPG suites.
Overall, the geochemistry of IA+Syn, NHSG and POPG suites is distinct from the enriched mantle of the AAPG suites. It becomes apparent that the difference must lie in the interplay of subducting oceanic/continental fragments at the base of lithosphere and asthenospheric (OIB like) upwelling isolated from plate boundaries.
220 The most favoured mechanism for the LREE enrichment of IA+Syn, NHSG and POPG melts is the development of a lower crustal MASH (Melting, Assimilation, Storage and Homogenisation) zone. This process was introduced by Smithies et al. (2011), to explain similar long lived intra-plate magmatism in the Musgrave Province, Australia. This would support the melting and contamination of lower lithosphere at plate boundaries as supported by N-MORB mafic magmatism. The MASH storage zone would then homogenise and allow mantle plumes to tap off and fractionate towards the surface. This can account for all the granitoids that are associated with suture zones. However, there is a distinction between enriched mantle AAPG suites that are associated with delamination processes. It is suggested the crust above the MASH zone becomes so dense that it eventually subsides causing lithospheric delamination and the influx of new enriched mantle material. This is discussed further in Chapter 7.5.
One of the difficulties in distinguishing these fractionated suites from AAPG suites is that they contain both ferroan/magnesian and within plate/volcanic arc characteristics (Figures 4.9 and 4.14), hence N-MORB and enriched mantle fractionation patterns. This transition is an interesting phenomenon that is thought to be associated with slab tear (Gvirtzman and Nur, 1999). As previously mentioned, the NHSG contaminated melts are N-MORB units associated with subduction and melting of the lower lithosphere. The granitoids that are derived from this MASH zone are initially perthitic with more magnesian VAG like affinities. This is seen in the Al Hafoor units and the early felsic products of the Kawr Suite.
There is a change in mantle chemistry which becomes more juvenile, more ferroan, WPG classified and the appearance aegirine-bearing mineralogy. This is marked within the discrete zircon morphologies of the Kawr and Wadbah Suites and the occurrence of the Ibn Hashbal Suite and is discussed further in Chapter 7.3. It becomes obvious that something has caused a change in the mantle behaviour of the lower crustal MASH zone. The suture related scenario of these granitoids places doubt on the sudden occurrence of lithospheric delamination. Furthermore, even the most evolved samples are neither isotopically nor geochemically similar to any lithospheric AAPG suites. It is therefore suggested that there is a tear in the subducting slab allowing a sudden influx of asthenospheric (OIB like) mantle into the lower crustal MASH zone.
221 This could account for the following: 1) transition from IAT to MORB units within the same suite; 2) increasing isotopic juvenility; 3) ferroan nature; 4) increase in incompatible elements; 5) switch from N-MORB fractionating trends to enriched mantle trends (zircons); and 6) discrete multiple zircon age groups with different geochemistry within the same suite. The recharge of this MASH zone is summarised in Chapter 7.3.
7.3 Magmatic Pulsing in a Contaminated MASH Zone.
One of the most interesting phenomena found in Arabian Shield geochronology is the separation of discrete magmatic ages and zircon morphologies within a given suite (Chapter 6). This is found within the IA+Syn suites associated with oceanic accretion, but also in NHSG intrusions affiliated with the Nabitah Suture zone. These are classic aegirine-bearing felsic alkali-granites, which are coined A-type granites (Chapter 4.4.4a). The most significant aspect of these suites is they possess a transition from contaminated N-MORB like mafic melts (Chapter 4.2) to enriched mantle melts that produce aegirine absent and bearing perthitic endmembers (Chapters 4.2 and 4.3). This is not limited to whole rock geochemistry, but also strongly reflected in zircon geochemistry. The NHSG suites are geochemically distinguished from similar AAPG suites (discrete zircon population absent) and form the basis for proposing the following magmatic pulsing scheme.
Prior to any geochemical interpretation, it is important to highlight the complex mingling field relationships observed only in the NHSG intrusions. The Kawr Suite is confined to the southern Asir terrane (Figure 7.1) and compositionally ranges from gabbros to aegirine-bearing alkali-granites (Chapter 2.3.3). Multiple mingling phases between mafic and felsic endmembers is observed in autolith and sill like forms.
Gabbroic autolithic units are incorporated into both the grey intermediate (~65% SiO2) style granite and pink hypersolvous perthitic alkali-granite. The finer grey intermediate granite is interrupted and confined by the coarse perthitic granite (Chapter 2.3.3). Already the differences in granitic style reflect obvious changes in magma chamber processes that produce similar end products to that of granites found in Padthaway
222 Ridge, Australia (Turner et al., 1992). It would therefore be unsurprising if the samples reveal not only different geochemical parameters, but also discrete zircon populations. This field evidence will be reinterpreted after the presentation of the geochemical evidence.
Following from Chapter 7.2, it is felt necessary to briefly emphasise the important geochemical characteristics of both the NHSG intrusions and older IA+Syn suites. Island arc (Makkah Suite) mafics and fractionated granitic endmembers (Makkah Suite, Shufayyah and Jar-Salajah Complexes) contain amongst the lowest major and trace elements of any suites sampled in the Arabian Shield and are synonymous with contaminated N-MORB chemistry (Chapter 4.2). NHSG mafics (Kawr and Al Hafoor Suites) are also associated with contaminated N-MORB mantle (Figure 4.15), which is possibly contaminated with the nearby Paleoproterozoic Khida terrane (Figures 4.6- 4.8). Isotopically, NHSG mafics fractionate to produce two A-type endmembers: contaminated perthitic alkali-granites (Al Hafoor Suite); and enriched aegirine-bearing alkali-granites (Kawr Suite). The significance of the transition into the enriched juvenile mantle zone (<600Ma AAPG suites) will be discussed shortly.
Most importantly, NHSG mafic endmembers clearly indicate the presence of crustally contaminated mantle, which is isotopically distinguished from the <600Ma mafics associated with enriched juvenile mantle (Figures 4.6-4.8). As discussed in Chapter 7.2, contaminated mantle characteristics are suggestive of a lower crustal MASH zone (Smithies et al., 2011), which allows the development of depleted N- MORB magmatism (LREE contamination) that fractionates towards the surface. This mantle is isotopically and geochemically distinct from the enriched AAPG asthenospheric (OIB like) mantle, characterised by the absence of LREE contamination, HREE enrichment and limited crust-mantle interaction (Chapter 4).
The most interesting characteristics of IA+Syn and NHSG intrusions are their discrete zircon morphologies (Chapter 3.2). Within each suite, the data typically spans ~50Myr which is a large window of magmatism. This is especially an anomaly for A- type magmatism considering the AAPG suites are commonly <20Myr. Based on the methods in Chapter 6, these zircons are spilt into distinguished morphologies,
223 geochemical properties and also age groups. The geochemical trends of NHSG samples are the most pronounced and so will be used in the following discussion.
Both the IA+Syn and NHSG zircon geochemistry agrees with whole rock data trends. As established in Chapter 7.2, the Kawr Suite isotopic signatures are dominated by an N-MORB like mantle with a contaminated source. The whole rock isotope signatures fractionate from less juvenile mafic endmembers and increase in juvenility towards IA+Syn/AAPG fields (Figures 4.6-4.8). Once again, these trends are exhibited between different morphologies in the same suite (Figure 5.1). The increasing Hf content with decreasing age is consistent with the incorporation of a more juvenile source. The Kawr Suite shows two trends: 3 discrete morphologies within kw42 increasing in juvenility; and an aegirine-bearing alkali-granite (kw51p), which is the most juvenile (Figure 5.1).
These trends continue with incompatible elements (Figures 5.4 and 5.5). The oldest IA+Syn suites define an N-MORB like trend to which the non-economic perthitic granitoids form. The more evolved granitoid endmembers include the 636Ma Al Hafoor Suite and oldest zircon population (636Ma) of the Kawr Suite. The most interesting phenomenon occurs within the Kawr Suite. There is a distinct transition of the younger zircon populations (609Ma and 594Ma) into the enriched fractionation field defined by the AAPG suites. This trend is capped with the most enriched aegirine-bearing Kawr Suite sample at 608Ma. Together with the appearance of the ferroan Ibn Hashbal and Wadbah Suites, this trend is indicative of a change in mantle chemistry below the Nabitah Belt. This is supported by the whole rock geochemistry (Chapter 4). Initial NHSG subduction related melts fractionate to magnesian endmembers and are then suddenly interrupted by the appearance of the younger NHSG ferroan suites.
Most importantly, the NHSG intrusions show discrete zircon morphologies with easily distinguished geochemical patterns. These initiate with contaminated N-MORB like patterns synonymous with a volcanic arc like setting and transition to enriched WPG style patterns similar to AAPG suites (Figure 5.6). It should be emphasised that the Kawr Suite whole rock chemistry also displays this transition from MORB/IAT mafics to VAG/magnesian and finally aegirine WPG/ferroan alkali-granites (Figures 4.12-4.15). Regardless of the interpretation of the discrete zircon morphologies, it is
224 clearly established that the NHSG granitoids, although aegirine-bearing, are geochemically distinct from AAPG suites. As outlined in Chapter 7.2, this is attributed to the development of a lower crustal MASH zone as opposed to WPG lithospheric delamination (see Chapter 7.6).
The subtle differences between zircon morphology and correlating geochemistry (Chapters 5 and 6) suggest that the Nabitah Suture intrusions are the result of a long- lived MASH zone (Smithies et al., 2011) with multiple extractions of magmatism or ‘magmatic pulses’. One might argue that the increasing juvenility and enrichment in trace elements could simply be the result of one initial pulse that has undergone intense fractionation and decompression at the surface. This seems plausible for the single age (636Ma) Al Hafoor Suite, which initiates with contaminated IAT mafics and terminates with perthitic non-economic granitoids. However, the Kawr Suite contains multiple zircon populations and both MORB and IAT mafics. These appear to be derived from the same source as the Al Hafoor mafics (similar geographic location), but fractionate into the aegirine-bearing ‘economic’ zone associated with enriched juvenile mantle (Chapter 5). The Kawr Suite also contains complex mingling textures (start of this section) that illustrate influxes of more mantle like material into felsic units, thus increasing the chance of multiple zircon phases. A similar study was undertaken by Schaltegger et al. (2002) who explain multiple discrete ages and mantle sources within a given suite (Kohistan Island Arc, Pakistan) are the result of magmatic pulses.
It could be also argued that the change in zircon geochemistry is reflective of continued inheritance from remelting of the same granitic source. It is acknowledged that the incompatible elements would fractionate and incorporate less and less crust and may eventually expose the mantle below. This mantle would be responsible for producing the similar age (636Ma) and isotopically similar Al Hafoor and Kawr Suite mafics. However, the major and trace element, and isotope geochemistry of the felsic granitic products place these into isotopically distinguished mantle zones (Figures 4.6- 4.8). The Kawr Suite contains both VAG/magnesian and aegirine WPG/ferroan endmembers, which seems unlikely to be one homogeneous source, but rather a contaminated mantle that changes in composition as a result of changing tectonic processes. This also would accommodate the possibility of magmatic pulses, hence discrete zircon ages/geochemistry.
225 The zircon and whole rock geochemistry is indicative of multiple N-MORB like plutons extracted from the lower crustal MASH zone at 636Ma. This contaminated melt fractionated towards the surface producing the ‘plain’ perthitic VAG granitoids of the Al Hafoor and Kawr Suites (Figures 5.4 and 5.5). This pulse represents the initial melting of the lower lithospheric mantle (Asir plate) beneath the Nabitah Belt. The depleted mantle is possibly contaminated with the nearby Khida terrane (Figures 4.6- 4.8) and produces the MORB and IAT mafics found in the Al Hafoor and Kawr Suites. At ~618Ma there is a change in mantle source behaviour because of the occurrence of NHSG ferroan plutons such as the Ibn Hashbal and Wadbah Suites. This is also notable within the Kawr Suite. It is suggested that these granitoids mark another magmatic pulse from this zone, but this zone is now enriched in trace elements.
This recharge is thought to resemble the initiation of a tear in the subducting Asir plate, allowing the influx of asthenospheric (OIB like) mantle into the depleted MASH zone. The incremental slab rollback/tear (Gvirtzman and Nur, 1999) can account for the transition to more enriched/ferroan granitic products. Although this asthenospheric mantle is similar to AAPG suites, it enters a depleted/contaminated lithospheric mantle and is given a chance to homogenise/assimilate into the lower MASH zone (~10Ma between pulses). This produces NHSG samples that are ferroan and classified as WPG, but are still distinguished from AAPG mantle sources (Chapter 4.4.4b).
The MASH zone processes may also account for the transition between VAG and WPG classified samples within the Kawr Suite. This may resemble the intermediate grey granite found in the Kawr Suite quarry (Chapter 2.3.3). It is interpreted that there is one last magmatic pulse at 594Ma before the lower lithospheric source thermally homogenises. This may represent the coarse pink and aegirine-bearing alkali-granites, which are the result of final slab tear creating rapid decompression. The deactivation of this MASH zone is thought to be the result of a relief in lithospheric pressure (slab rollback) cased by the final amalgamation of the Gondwanian fragments (Chapter 8.6). These incremental recharge MASH zone processes are summarised in Figure 7.2.
226 Figure 7.2: A tectonic model representing the Asir-Tathlith terrane corresponding with section C in Figure 7.1. Part A) The 636Ma Kawr, Al Hafoor and Wadbah Suite felsic endmembers are all classic perthitic ferroan granitoids that are initially magnesian, syncollisional-anorogenic and WPG/VAG classified (Chapter 4.4). Examination of the Kawr and Al Hafoor Suite mafic endmembers reveals IAT and MORB like gabbros that contain contaminated trace element signatures (Chapter 4.2). The crustal component appears to isotopically correlate with the nearby Khida terrane (Chapter 4.3). Part B) The younger zircon populations in the Kawr and Wadbah Suite become increasingly enriched in incompatible elements and are interrupted by the ferroan Ibn Hashbal Suite at ~618Ma. Interestingly, this coincides with the transition of the Kawr Suite whole rock chemistry (Chapter 4.2), isotope chemistry (Chapter 4.3) and discrete zircon chemistry (Chapter 5). The felsic Kawr Suite endmembers also start to show the appearance of aegirine mineralogy similar to the AAPG suites, but are still easily distinguished using incompatible elements (Chapter 4.2). This transition in geochemistry represents a change in mantle behaviour and is explained by a tear in the subducting oceanic plate beneath the Nabitah Belt. This influx of enriched mantle recharges the MASH zone (Smithies et al., 2011) and continues to generate magmatic pulses as reflected in the discrete zircon populations (Chapters 3.2 and 6). This transition also explains why the contaminated Nabitah Belt perthitic granitoids are distinguished from lithospheric AAPG suites and is discussed previously in Chapter 7.
227 7.4 Subtle Differences in Primitive Syenites; Two Mantle Sources.
As outlined in Chapter 4.4.4b, there are distinctive geochemical parameters that define contaminated and enriched mantle granitoids. The previous section described contaminated IAT and MORB like mafics in NHSG suites that are easily distinguished from enriched juvenile mantle AAPG suites. However, the absence of mingling textures within similar age POPG and AAPG suites creates a more difficult scenario to discriminate them. Fortunately, the Hijaz terrane contains two easily distinguished primitive syenitic endmembers and a similar age gabbro (600Ma Rithmah Complex) that shed light on the mechanisms that produce the final felsic products. The following discussion uses these syenites/gabbros in a similar manner to which mafic units within the same suite are used to infer petrogenetic properties. It is therefore important to clearly establish the geochemical differences between these two endmembers and how they relate to the POPG and AAPG felsic products.
The syenites are the least evolved granitoids and contain ages of 599.2Ma (Admar Suite) and 525.6Ma (Mardabah Complex), which are the youngest units sampled in the Arabian Shield (Chapter 3.2). Both contain classic perthitic A-type mineralogy, but are separated by the presence of olivine in the Mardabah Complex (Appendix 1.3.4). The Admar Suite is sandwiched between the Yanbu and B’ir Umq Sutures, whilst the Mardabah Complex forms small within plate plutons in the same terrane (Figure 7.1). The widespread nature of the Admar Suite and its geochemistry suggests volcanic arc magmatism creating an ideal comparison with the younger, within plate geochemistry of the Mardabah Complex..
POPG and AAPG syenites share similar major element affinities dominated by low SiO2 (~60 wt %), high Na2O+K20 (~9.8-11.2 wt %), Al2O3, (~18-18.5 wt %) TiO2 (~0.7-0.93 wt %), CaO (~2.3-3.2 wt% and Mg# (~0.25-0.41), hence their ‘primitive’ nature (Chapter 4.2). They are also both metaluminous and strongly alkali, but are separated into ferroan (WPG, Mardabah Complex) and magnesian (VAG, Admar Suite) endmembers (Chapter 4.4). Due to their identical silica content the differences in iron and alkali abundance are the only means of major element separation (Figure 4.1). However, both suites are easily discriminated using incompatible trace elements parameters. This is particularly notable with Nb, Y, Nd and Ga, which illustrate up to a
228 ~10 fold higher abundance with the Mardabah Complex (Figures 4.2 and 4.3). Unsurprisingly, the Admar Suite (VAG) suite contains geochemical parameters associated with VAG signatures, whilst the Mardabah Complex (WPG) contains similar properties to the most evolved granitoids in the Shield. This is reflected in their tectonic emplacement in relation to the Yanbu Suture (Figure 7.1).
One of the most important trends is illustrated in Figure 4.3, which utilises incompatible elements to clearly separate all syncollisional, POPG and NHSG units from AAPG granitoids. This highlights the linear fractionation trend from an N-MORB like mantle that produces all POPG suites that never interact with the AAPG field (incorporates AAPG syenite). The AAPG field is thought to resemble enriched asthenospheric (OIB like) mantle and is explored further using trace element signatures (Figure 4.4). These trends reveal that both Admar and Mardabah syenites are enriched in LREE, but are separated by the presence of higher HREE abundances in the AAPG syenites. Most importantly, the Admar syenite exhibits strong LREE depletions in Nb and Th that indicate contaminated arc like patterns. These are distinctly absent in the Mardabah syenite. Both are compared to the depleted ~600Ma gabbroic (IAT, Chapter 4.4.3) Rithmah Complex, which is found in the same vicinity.
The identification of different mantle sources is reinforced with whole rock isotopic analyses. Figure 4.7 highlights the affinity of POPG units with N-MORB type mantle, which are isolated from enriched juvenile AAPG suites (uses Nd (t) vs. Nb). Figure 4.8 illustrates that although these syenites/Rithmah gabbros are derived from more enriched mantle than suture mafics, the AAPG syenite contains a higher Fe# than POPG and Rithmah endmembers. This is suggestive of asthenospheric (OIB like) mantle associated with the AAPG syenite. Zircon geochemistry also reflects differences in mantle sources with higher incompatible elements associated with the AAPG syenite, hence asthenospheric mantle (Figures 5.2-5.5). Once again, the trace elements are compared in Figure 5.6 and reveal identical trends to the whole rock chemistry described above.
Overall, the geochemical differences between the syenites rule out the possibility of a common source. These are easily distinguished as VAG and AAPG suites and clearly are the least evolved granitoids in their respective categories. Even
229 though they have both experienced rapid uplift (perthitic nature) it is assumed that if allowed to continue to fractionate, these melts would produce the felsic endmembers in their respective fields. This is actually observed with many of the geochemical figures in Chapter 4.2. There is a distinctive lateral style fractionation when using the major elements such as SiO2 and Na+K (Figure 4.1) whereby only silica increases towards the most evolved units in their field. This is very different from the MORB curve displayed by the NHSG intrusion. It is therefore justified that these represent the early stages in POPG and AAPG generation, which can be extrapolated on a lithospheric scale.
The volcanic arc like signature displayed by the Admar Suite is compatible with contamination and the suite is located in the vicinity of two oceanic plate suture zones (Figure 7.1). One key to determining the mechanism in which the Admar syenite formed is by the examination of the nearby similar age 600Ma gabbroic Rithmah Complex. This has been classified as IAT units (Chapter 4.4.3), which are symbolic of lower lithospheric melting in the initial stages of extension (Peace et al., 1984b). The age of the older (~730-670Ma) contaminated syncollisional suites would place doubt on whether the Midyan oceanic slab is still subducting at ~600Ma. However, it is noted in Chapter 8.6, that the African and South American Continents were still colliding until ~650Ma placing strain on the northern Mozambique Belt.
The ~50Myr window between the collision of the African and South American continents and the appearance of the Admar IAT melts (extension), suggests that the pressure of moving continents was temporarily relieved, causing the SE migration of the Midyan slab to almost cease. This allowed the opportunity for crustal spreading and development of the lower MASH zone (see Chapter 7.3). It is suggested that the Admar Suite is a derivative of a melt extracted from this lower crustal zone accounting for its LREE contaminated N-MORB like geochemistry. The widespread nature of the Admar Suite coupled with its perthitic mineralogy and primitive geochemistry, suggest rapid uplift from the mantle source. Pearce et al. (1984b) indicate that the degree of arc spreading depends on the angle of slab roll back processes. This highlights the possibility of the Midyan plate rolling back over ~50Ma, eventually allowing the large volume spreading in the Hijaz terrane at ~600Ma. This created the opportunity for the lower crust to melt and produce the Rithmah IAT mafics and slightly more evolved contaminated syenites. This mechanism is summarised in Figure 7.3.
230 As described above, the Admar syenite is a great example of typical post- amalgamation suite associated with slab related processes, but is not a product of WPG enriched mantle. The appearance of the geochemically enriched AAPG syenite ~75Ma later in the same vicinity clearly indicates a change in mantle behaviour. The localised small discrete plutons of the Mardabah Complex (Figure 7.1) indicate slab roll back processes initiated ~75Ma earlier are well and truly finished. There is also no geochemical evidence for contaminated N-MORB source suggesting that this is not associated with the lower crustal MASH zone. Prior to this there is also no reintroduction of calc-alkaline magmatism which one would expect with a continued migrating slab. This suggests that this new enriched mantle source is formed from a completely new mechanism to that for the older POPG suites.
As outlined in Chapter 8.6, the 525.6Ma age of the Mardabah Complex is synchronous with the ~530Ma collision of India and the amalgamated African fragments during the final stages of Gondwana assembly. It is proposed that this AAPG syenite is not the product of lithospheric delamination (see Chapter 7.6), but localised extension (crustal thinning after collision). The small volume and the primitive nature of this suite rule out continental scale lithospheric delamination, which is observed in other parts of the Shield (e.g. Abanat Suite). It is inferred that this localised extension is a product of the Najd Fault reactivation (Kusky and Matesh (1999) date the Najd system at 576.6±5.3Ma) created by the final collision of Gondwana. This area of the Hijaz terrane has already been thermally weakened by previous syncollisional and post- collisional magmatism. This provides the ideal environment for a tear in the crust, allowing the asthenospheric mantle to rapidly migrate towards the surface. The significance of this suite is to emphasise the change from contaminated to enriched mantle chemistry, thus a tectonic mechanism which produced seemingly similar perthitic syenites. This is summarised in Figure 7.3.
231 Figure 7.3: A tectonic model representing the Midyan-Hijaz terrane corresponding with section A in Figure 7.1. Part A) The 600Ma Rithmah Complex (rt) gabbros are classified as IAT units and contain an N-MORB like arc signature synonymous with melting of the lower lithosphere. These units are thought to rise quickly through the crust without assimilation during extension related settings. The similar age (599.2Ma) Admar Suite is a magnesian rich perthitic syenite relatively low in incompatible elements and a contaminated arc like signature (Chapter 4.2). These geochemical characteristics are suggestive of the generation of a similar IAT melt, but minor amounts of crustal assimilation/fractionation. The Admar Suite also is emplaced into an extensional setting and rose quickly to the surface. Part B) The Mardabah Complex appeared ~75Myrs later in almost the same place. Similar to the Admar Suite, this is also a primitive perthitic syenite. However, this is a WPG ferroan suite with easily distinguishable incompatible element abundances (Chapter 4.2). This also doesn’t contain a contaminated arc like signature and is more enriched in HREE (Chapter 4.2). The oceanic Midyan plate has well and truly migrated away from this spot and is no longer influencing the geochemistry. The final collision of Gondwanian fragments (~530Ma) is thought to have reactivated the Najd Fault system creating localised extension. This thinned above crust allows the upwelling of enriched mantle to reach the surface with relatively little fractionation. The distinction between the two tectonic processes is discussed further in Chapter 7.4.
232 7.5 Enriched Mantle Within Plate Granitoids; Key to Economic Deposits.
The Abanat, Ar Ruwaydah and Al Bad Suites are the most geochemically evolved suites of all granites sampled in the Arabian Shield. These anorogenic (<600Ma) within plate units are spread across the Ha’il-Afif-Ad Dawadimi and Midyan terranes respectively and intrude younger contaminated VAG suites such as the Idah Suite and Najirah Granite. Most importantly, these AAPG suites contain the highest HREE abundances (Chapter 4.2) and are commonly associated with REE deposits such as W, Nb, Ta, Mo, U, Ag and Au (Johnson, 2006). One obvious question is how do WPG tectonic mechanisms differ from mineralogically similar, but slightly older suture related aegirine-bearing alkali-granites. The Abanat and closely associated Idah Suite alkali-granites are great examples to compare the transition from ‘plain’ VAG to economic WPG tectonic environments and are used in the following discussion.
Prior to any discussion about the tectonic mechanism, it is important to establish a clear geochemical distinction between the most evolved AAPG Abanat Suite (585Ma) and most evolved POPG Idah Suite (607.9Ma). As illustrated in Chapter 2, both of these suites share similar perthitic mineralogy, but are separated by the presents of aegirine in the Abanat Suite. It is therefore unsurprising that they both contain similar concentrations of SiO2, Na2O/K2O, FeO, MgO, CaO and are classified as ferroan, alkali-calcic and peraluminous/peralkaline (Chapter 4.4). However, this is where the similarities end. These two groups are easily distinguished using incompatible elements such as Nb, Y, Zr, Ga and Ce/Yb vs. Nb/Y ratios (Figures 4.2 and 4.3) with the Abanat Suite often containing 10 times the abundance of the Idah Suite (Figure 4.5).
These trends continue when examining their isotopic and zircon geochemistry. AAPG suites contain distinctive Nd isotope signatures which isolate them from typical N-MORB fields (Figure 4.7). Theses are confined to more juvenile mantle with high Nd (t) and Nb parameters. It is suggested that AAPG suites are fractionated from an enriched juvenile mantle constrained by the AAPG syenite. POPG suites are also fractionated from this zone, but the POPG syenite is geochemically depleted and consistent with crustal contamination (Chapter 4.2). This fractionates to produce Idah Suite perthitic alkali-granites absent of aegirine mineralogy and are affiliated with the
233 N-MORB zone when comparing Nd (t) with Nb. The Idah suite is clearly isolated from all AAPG suites (including the AAPG syenite), containing both a lower Nd (t) and Nb value. The zircon chemistry reveals overlap between these two suites because they are the most evolved suites in their respective POPG and AAPG fields. However, they are products of opposing fractionation patterns (Figures 5.2-5.5) with sources derived from an N-MORB (POPG trend) and enriched mantle (AAPG trend) like source.
Now that a geochemical distinction has been established, the change in tectonic settings will be discussed. The older Idah Suite is juxtaposed to the Nabitah Suture and contains geochemical characteristics consistent with contaminated lower crustal melts (see Chapter 7.3). This suite is associated with localised mesothermal Au deposits, hence is highly economic (Johnson, 2006), but has relatively low REE. It is proposed that this suite, like all contaminated mantle perthitic granitoids, is the product of a lower crustal MASH zone (Smithies et al., 2011). This enhanced the density of the continental crust in the Ha’il and Afif-Ad Dawadimi terranes and caused crustal subsidence. This allowed the deposition of halide rich basins such as the 600Ma Hadn formation. Eventually, the lithosphere became so dense that it delaminated (Avigad and Gvirtzman, 2009) and allowed the upwelling of enriched (OIB like) asthenospheric mantle.
The Hijaz plate underneath the Nabitah Suture is associated with the generation of 607.9Ma Idah Suite MASH Zone in the Ha’il terrane which dissipated by the time the 585Ma Abanat Suite formed by lithospheric delamination. One might argue that the change in mantle chemistry between the Idah and Abanat Suites is the result of slab tear rather than lithospheric delamination. It is suggested this is invalid because the AAPG suites are geochemically and isotopically distinct from NHSG intrusions that exhibit slab tear processes (Chapter 7.3). The Al Bad Suite confined to the Midyan terrane on the opposite side of the Shield (Figure 7.1) is similar both geochemically and economically to the Abanat Suite and is clearly not associated with plate boundaries.
It is interesting to note the timing of the halide basin forming so quickly after the Idah Suite formation. The economic AAPG suites obviously mark a change in mantle chemistry, but the question that still remains is whether the enrichment happens lower in the crust or closer to the surface. There is no doubt that AAPG suites are the result of rapid decompression due to their non-existent contamination (Chapter 4.2) and absence
234 of mingling textures and perthitic mineralogy (Chapter 2). This raises the issue of the excess F that is commonly associated with these suites (fluorite grains in Chapter 2).
One possible scenario is the late stage incorporation of a halide sedimentary basin (high in Sr) concentrated by localised faulting in near surface conditions e.g. Hadn Formation in the Ha’il terrane. Both the Abanat and Al Bad Suites are highly evolved and derived from a similar enriched juvenile source (Chapter 4.3). It is suggested that fractionation from enriched mantle is by itself not sufficient to produce economic plutons (not all AAPG are economic). It has been isotopically and geochemically outlined that AAPG are derived from limited crust-mantle interaction, whilst the POPG units are initially contaminated and produce the Idah Suite. The change in mantle chemistry between AAPG and POPG suites suggests a change in tectonic setting, which can account for late stage extension and deposition of halide basins.
The Slightly older (607Ma) contaminated Idah Suite suggests the lithospheric mantle (N-MORB like) assimilates the overlying continental crust and produces melts that contain U and Au anomalies (Figure 4.5). However, these are not enriched in HREE which are often sought after. As seen in similar N-MORB contaminated NHSG intrusions, lower lithospheric melts can be geochemically changed by the influx of enriched mantle (OIB like) associated with slab tear. However, it is suggested that this small volume of new melt is quickly assimilated and homogenised in the depleted lower crustal MASH zone and is unable to produce economic HREE deposits.
By contrast, the upwelling of enriched (OIB like) asthenospheric mantle produced the HREE enriched Abanat suite, which has the same geographical location as the Idah Suite, but geochemically has had little curst-mantle interaction (devoid of REE anomalies, Chapter 4.2). This would suggest that any crustal assimilation was late stage and possibly coincides with the deposition of isotopically similar Hadn Formation (Figure 4.8). This basin sample resides in the juvenile field located between the Mardabah syenite and the Abanat Suite. It is possible that an enriched source similar to the Mardabah syenite fractionated and incorporated this halide basin higher in the crust. This could produce the excess fluorine commonly associated with economic AAPG suites. The mechanisms that indicate the transition from ‘plain’ perthitic VAG (Idah) suites to economic perthitic WPG (Abanat) suites are summarised in Chapter 7.6.
235 7.6 Within Plate Granitoids; Products of Lithospheric Delamination.
Anorogenic (<600Ma) within plate granites are isolated from plate boundaries, high volume and widespread plutons that appear ~100Myrs after initial collision, and suture formation. As established in Chapter 7.5, these are economic granites that have distinctive enriched trace element patterns, isotopic signatures and zircon REE trends that clearly separate these suites from all other granite samples in the Arabian Shield. These Ediacaran age suites include the Abanat, Al Bad, Al Hawiyah and Ar Ruwaydah Suites (Figure 7.1).
The timing, isolation from plate boundaries and geochemistry of the above suites places doubt on the involvement of subduction related processes. This is in agreement with Kay and Kay (1993), Schott and Schmeling (1998), Elkins-Tanton (2005), and Avigad and Gvirtzman (2009), who suggest that this process cannot account for the repeated cycles of accretion observed in the Arabian-Nubian Shield (Chapter 8). AAPG granitoids are geochemically distinguished from contaminated N-MORB like mantle (MASH zone) that produces POPG suite units (Chapter 7.3). The change between the Idah Suite (POPG) and enriched Abanat Suite (AAPG) on the eastern side of the Shield (Ha’il terrane) provides the best example to highlight the change in lithospheric processes and mantle chemistry. Both are perthitic iron rich plutons on the eastern side of the Nabitah Belt, but are formed ~20Myrs apart, cover the same crust and produce similar volumes of magmatism. These form the basis for this discussion.
Despite the unknowns about the petrogenesis of both suture and within plate A- type suites, it is clear that these are characterised by regions of uplift and crustal extension. Partial melting of their sources requires heat supply and, whatever the origin, results in thermal erosion and/or mechanical delamination of lithospheric roots (Black and Liegeois, 1993). Great controversy surrounds the mechanism that causes extension and providing heat supply to the lithosphere. One idea proposed by Stein and Goldstein (1996) and Stein and Hofmann (1992) is that a rising plume from the enriched lower mantle actually forces the upper crust to extend and provide the heat necessary to partially melt the crust and mix the two sources. However, this seems highly unlikely and coincidental to account for repeated cycles of post-orogenic magmatism covering an area the size of the Arabian Shield.
236 It could be argued that mantle plumes follow accretionary events (Stein and Goldstein, 1996) and melt the lower lithosphere, become contaminated and produce suites such as the 607Ma POPG Idah Suite. However, there is a distinct change in mantle chemistry at 585Ma with the much enriched Abanat Suite. Why a second plume is released in exactly the same location ~20Myrs later and covers the same vast areas of the Shield seems too convenient to explain the enriched mantle source scenario. Following on from this Kay and Kay (1993), Schott and Schmeling (1998), Elkins- Tanton (2005), and Avigad and Gvirtzman (2009) suggested that it is possible to create enriched granitic magmatism by the removal of the lithospheric root caused by denudation. Lithospheric delamination is the preferred model to explain the geochemical difference between contaminated and enriched mantle suites.
One of the key issues surrounding the denudation of the lithospheric root is what causes the density increase required for detachment into the asthenospheric mantle (Elkins-Tanton, 2005). It is therefore necessary to establish the relationship between deformation and melting of the lower crust. Prior to the appearance of any anorogenic magmatism, the collision between lithospheric fragments typically produces a major orogenic episode e.g. Himalayas and Pan-African Orogeny. Although anorogenic granitoids appear to be disconnected to orogenic events it is suggested they are related at a lower crust level emplaced up to 50Myrs after initial collision (Whalen et al., 1987). An excellent summary of the transition from orogenic to anorogenic magmatism is discussed by Bonin (1990).
In terms of the Arabian Shield, this lower crustal relationship is significant because of the intense folding associated with many anorogenic suite locations e.g. Nabitah Orogenic Belt (Figure 7.1). It is suggested that the collision of the microplates caused intense deformation of the lower lithosphere, possibly inducing high grade facies metamorphism (e.g. evidence in ophiolite belts). The subduction of oceanic plates is coupled with generation of contaminated lower crustal MASH zone (Chapter 7.3). This subduction is reflected in contaminated N-MORB like VAG signatures such as the Idah Suite. The lower crust becomes so dense that it begins to subside. This phenomenon is associated with crustal extension and provides the window of opportunity for sedimentary basin deposition.
237 The 600Ma Hadn formation in the Ha’il terrane is an example of a post- amalgamation basin following the crystallisation of the Idah Suite at 607Ma. This is thought to be incorporated at a late stage into the already enriched (OIB like, limited crust-mantle interaction, Chapter 4) Abanat Suite creating an economic HREE deposit. In any case, it is suggested that the already deformed/melted continental lithospheric root became so dense by the addition of the iron rich VAG suite, it delaminated by 585Ma. This allowed the upwelling of asthenospheric (OIB like) mantle and produced the economic Abanat Suite in the same location as the Idah Suite in the Shield (Figure 7.1). This process seems to be most suitably explained by lithospheric delamination. This is not an isolated case, but also occurs in the western Shield (see Chapter 7.5). It is acknowledged that the Abanat Suite would also incorporate the Idah Suite and one might argue the Abanat Suite is simply the continued remelting and fraction of the Idah Suite from the same mantle source. However, this seems unlikely due to their distinguished N-MORB and enriched mantle geochemical parameters (Chapter 4), suggesting a chance in mantle source, hence tectonic process. The transition from lower lithospheric melting to lithospheric delamination is summarised in Figure 7.4.
7.7 Generation of Crustal Melts.
The Malik Granite contains the only garnet-bearing mineralogy (Appendix 1.5.2) sampled in the Arabian Shield and defines the leucogranitic intrusions geochronologically coeval with the neighbouring Idah Suite (Figure 7.1). According to Clarke (1992), this mineralogy would clearly identify the occurrence of S-type melts in the Shield. However, as outlined in Chapter 4.4.4a, the Malik Granite contains a similar mantle source to those granitoids associated with contaminated N-MORB mantle. There is no question that the Malik Granite is clearly mineralogically different to other sampled plutons, but as shortly outlined, it contains similar geochemical parameters. This raises the issue of what exactly is S-type granite. Therefore, for the purposes of this discussion, this will be referred to as a garnet-bearing leucogranite.
As mentioned above, the Malik Granite intrudes the 607.9Ma Idah Suite on the eastern side of the Ad Dawadimi terrane and yields a slightly younger crystallisation
238 age of 599.6Ma (Chapter 3.2). As highlighted in Chapter 4.2, the major and trace element behaviours mimic those of the Idah Suite in which it intrudes. This is particularly noteworthy for incompatible elements such as Nb, Zr and Ga (Figures 4.2- 4.3). Exactly what the source of the excess Mn, Ca, Fe and Al required for garnet crystallisation is not clear. One thought might be that this is attributed to country rock assimilation and/or elemental crystallisation differentiation. However, the garnet- bearing granites only intrude slightly older non-garnetiferous Idah Suite alkali-granites. This is also coupled with the absence of foreign xenolthic inclusions, potentially eliminating the possibility of crustal contamination. Another more likely scenario is that garnet appears together with localised muscovite and is thought to crystallise from a highly evolved siliceous melt at the expense of hydrous biotite.
One method of supporting this idea would be to analyse the source melt that produced the Idah Suite and Malik Granite. This was achieved through zircon geochemical parameters (Chapter 5). Major and trace element zircon geochemistry exhibits almost identical patterns to those of wholerock samples (Figures 5.2-5.5). The highly evolved Idah Suite shows contaminated mantle signatures, volcanic arc like trends and an enrichment in LREE (Nb and Eu anomalies) followed by fractionation towards HREE. This pattern is closely mimicked by the Malik Granite, thereby suggesting an identical source.
As outlined in Chapter 7.3, the Idah Suite is an iron rich VAG suite geochemically synonymous with melting of the lower crust/subducting slab. This is juxtaposed to the Nabitah Suture zone in which the eastward migrating Hijaz oceanic plate collides with the Afif and Ha’il continental plates. This suite’s widespread, somewhat linear nature may resemble lower crustal melting at the forefront of a subducting system. This suite is not the product of lithospheric delamination unlike the geochemically distinct 585Ma economic Abanat Suite, which intrudes it with the same volume (see Chapter 7.5). That aside, the Malik Granite is surely a product of extreme fractionation from a melt gradually leaving behind Mg/Fe/Al, which finally crystallised the garnet-bearing leucocratic granite. Whether this melt is segregated and isolated from the Idah Suite chamber and allowed to fractionate at high crustal levels or is a direct extraction from the depleted lower MASH zone after the removal of the Idah Suite remains unclear. The process that generated these melts is summarised in Figure 7.4.
239 Figure 7.4: A tectonic model representing the Hijaz-Afif terrane corresponding with section B in Figure 7.1. Part A) The 607Ma Idah Suite is a widespread batholith east of the Nabitah Orogenic Belt, covering both the Afif and Ha’il terranes. This is classified as a ferroan VAG unit and displays similar geochemical abundances to that of the southern Kawr Suite (Chapter 4.2). The eastward migrating Hijaz oceanic plate coupled with its contaminated arc like signature (Chapter 4.2), suggest the melting of this subducting slab and/or lower lithospheric mantle of the Afif plate. The slightly younger (599.6Ma) Malik Granite intrudes the Idah Suite and is thought to be the result of melt segregation and fractionation from the same contaminated mantle source (Chapter 7.7). Part B) The 585Ma Abanat Suite is an economic ferroan WPG that is clearly differentiated from the older Idah/Malik granites with higher incompatible elements such as Nb and an enriched geochemical signature (Chapter 4.2). Similar to the Idah Suite, this covers the Ha’il and Afif terranes in identical proportions. However, this is thought to mark a change in mantle chemistry, hence tectonic process. The dense lower lithosphere is thought to be delaminated, consequently allowing the upwelling of enriched mantle. This suite possibly assimilates the Hadn Formation basin, increasing its economic significance.
240 Chapter 8: A Tectonic Synthesis of the Arabian Shield; Implications for Gondwana Assembly.
8.1 Geochronological Overview.
The analysis of 452 zircon grains from 19 granitic suites characterises 4 distinguished magmatic events covering 8 discrete terranes (Figures 8.1 and 8.2). These define a series of microplate island arc and continental accretion phases followed by post-tectonic, enriched magmatism (950-750Ma, 730-636Ma, <636-600Ma and <600Ma). This tectonic cycle (Bentor, 1985; Stern, 1994) is symptomatic of supercontinental breakup and assembly which is observed in many parts of Gondwana (Li et al., 2008). The dismemberment of Rodinia, hence the EAO event from ~1200- 950Ma, produced the opening of the Mozambique Ocean (Meert, 2003; Collins and Pisarevsky, 2005; Li et al., 2008; Johnson et al., 2011). The gradual reassembly (~950- 530Ma) of Gondwanian continental fragments saw the closure of this ocean and gave birth to juvenile accreted Arabian Shield arcs.
Figure 8.1: U-Pb concordia summarising 452 zircon analyses obtained from 19 Arabian Shield suites (Chapter 3.2). Values were processed and conveyed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000). It is clear that 4 distinct magmatism phases have occurred in the Shield. Post-orogenic and anorogenic phases mark microplate accretion and are thought to resemble the final assembly of Gondwana (Chapter 8.6 and 8.7).
241 Figure 8.2: 206Pb-238U probability plot summarising 452 zircon analyses (Chapter 3). Values were processed and conveyed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000). Note the 4 distinct phases of magmatism placed in a geological time frame constructed from geochronological data obtained from Doebrich et al. (2007), Hargrove (2007) and Johnson et al. (2011). A regional unconformity at ~542Ma marks the cessation of magmatism in the Shield (Johnson, 2006). However, anorogenic rift related magmatism is still occurring, thus suggesting a new unconformity boundary at ~500Ma. The separation of post-tectonic and anorogenic magmatism is interpreted to mark the transition between slab related and lithospheric delamination processes (Chapter 7).
242 8.2 Island Arc Magmatism (950-750Ma).
Makkah Suite units are confined to the northern Asir terrane (Figure 8.3) and record the oldest geological unit with an age of 867-829Ma (Chapter 3.2.1a). This island arc magmatism previously had a poorly constrained age of 817-687Ma and 859Ma), which apparently correlates with neighbouring units in Sudan (Johnson, 2006). The Makkah Suite forms a chain of mafic magmatism (Chapter 2.3.1), which is associated with ophiolite assemblages, and resembles another microplate suture known as the Jiddah Suture (Figure 8.3). The existence of this suture is not fully established (Johnson, 2006), but this island arc magmatism is interpreted to be the first fragment of juvenile crust in the western Shield. Ophiolite assemblages are synonymous with exposed remnants of oceanic lithosphere and the association of ophiolitic packages with the Makkah Suite, combined with its age (discussed shortly), suggests the addition of an island arc (accretionary suture zone) between the Hijaz and Asir microplates.
The analysed gabbro-diorite contains 3 discrete ages compatible with 3 distinguished zircon morphological groups. These are 867.6±8.5Ma, 847±4.3Ma and 829.2±6.2Ma respectively and are determined using the method in Chapter 6. The initiation of magmatism is marked with the presence of stubby prismatic zircons. These are interpreted to be the result of initial collision from eastward migrating EAO continental fragments causing subduction related N-MORB like (Chapter 4.2) melts. The appearance of needle like, simply zoned zircons is thought to represent a second magmatic pulse with the third less zoned group shortly after.
Multistage crystallisation appears to resemble 3 stages of incremental subduction, possibly resembling the closure of ocean basins (marked by forearc magmatism e.g. At Ta’if Group). This correlates with the eastward subducting Midyan plate or further abroad, the migrating fragments in the EAO occurring in distinct incremental phases (Trompette, 1997; Meert, 2003; Li et al., 2008). This suite is itself relatively undeformed (Chapter 2), but the timing is consistent with the low grade (greenschist) metamorphism observed in frontal arc rocks of the nearby At Ta’if Group (Chapter 2.3.1). These exhibit westward trending thrust kinematics and are dated at ~840-815Ma, which coincide with the timing of the 3 Makkah Suite pulses. The incremental magmatism also reinforces the validity of an island arc subduction suture
243 zone in the Jiddah terrane (discussed above). Perhaps the youngest group (829Ma) helps to constrain maximum age of suture collision. The generation of this suite is summarised in Figure 8.4.
Figure 8.3: A geological map of the Arabian Shield summarising the U-Pb zircon geochronology presented in Chapter 3.2. There are clearly 4 distinct magmatic phases: Island Arc=blue (~870-830Ma), syncollisional=green (~730-636Ma), post-tectonic=orange (~630- 600Ma) and anorogenic (~<600Ma). Some granitic units display multiple crystallisation phases (Chapter 6), which are thought to be associated with incremental subduction pulses of magmatic activity from a contaminated MASH zone (Chapter 7.3). These are differentiated from enriched within plate lithospheric delamination suites (Chapter 7.6). Sections A, B and C refer to Figures 8.4-8.6, which illustrate a series of cartoons summarising the tectonic mechanisms associated with the various Shield terranes.
244 Figure 8.4 part1: A tectonic model representing the Hijaz-Asir terranes corresponding with section C in Figure 8.3. Island arc magmatism obtained from the Makkah Suite (Chapter 3.2.1a) is the oldest unit sampled in the Arabian Shield and has geochemistry associated with contaminated N-MORB like magmatism (Chapter 4.2). This upwelling mantle gives rise to fore-arc magmatism in the Jiddah terrane (~870-830Ma). The migrating Hijaz slab also creates fore arc metamorphosed volcanic units such as the At Ta’if Group. The geochemical parameters associated with this magmatism are discussed in Chapter 7.
245 Figure 8.4 part2: A tectonic model representing the Hijaz-Asir terranes corresponding with section C in Figure 8.3. The closure of the ocean between the oceanic Asir and continental Afif plates also initiates the formation of the Nabitah Suture and related volcanics such as the Siham Group (~750-675Ma). The geochemical parameters associated with this magmatism are discussed in Chapter 7.
246 Figure 8.4 part3: A tectonic model representing the Hijaz-Asir terranes corresponding with section C in Figure 8.3. The appearance of post-tectonic magmatism at 636Ma marks the final phases of microplate assembly. The subducting oceanic Asir plate underneath the Afif continental plate systematically produces the Al Hafoor Suite and the initial phases of the Kawr Suite (development of a lower crustal MASH zone). Continued incremental subduction produces post-tectonic magma pulses of the Kawr, Wadbah and Ibn Hashbal Suites. The geochemical mechanism associated with the lower crustal MASH zone is discussed in Chapter 7.3.
247 Figure 8.4 part4: A tectonic model representing the Hijaz-Asir terranes corresponding with section C in Figure 8.3. Underneath the Nabitah Suture the incremental slab roll back of the Asir oceanic plate continues to produce post-tectonic magmatism associated with the Kawr Suite (MASH zone). Further to the east of the Shield in the Afif terrane, remnants of the subducting slab are thought to produce the Haml Suite. Many post-tectonic basins such as the Bani Ghayy and Murdama Groups have also appeared due to localised crustal sag. The geochemical mechanism associated with the lower crustal MASH zone is discussed in Chapter 7.3.
248 Figure 8.4 part5: A tectonic model representing the Hijaz-Asir terranes corresponding with section C in Figure 8.3. 600Ma marks the anorogenic magmatic phase with a rise of new granitic units. In the east, contaminated N-MORB like magmatism between the Afif and Ad Dawadimi plates is thought to produce the Al Khushaymiyah Suite. The final phases of the Kawr and Wadbah units to the west associated with the Asir slab roll back mark a change in MASH zone geochemistry (Chapter 7.3). The Al Hawiyah Suite is spatially isolated from plate boundaries and is classified as within plate batholith. This is thought to be produced from lithospheric delamination processes (Chapter 7.6).
249 8.3 Syncollisional Magmatism (736-636Ma).
The continued eastward migration of Gondwana continental fragments in the EAO placed great strain on juvenile Shield terranes. As a result, closure of oceanic plates in the northern terranes (Midyan, Hijaz and Asir) eventually accreted, producing ophiolite-bearing suture zones. These are the B’ir Umq and Yanbu Sutures (Figure 8.3) and are thought to have closed by 730Ma and 700-680Ma respectively (Johnson, 2006). The oldest unit defining this category is the Shufayyah Complex, which exhibits 3 discrete ages of 730.9±7.2Ma, 716.7±4.1Ma and 696.3.2±7.1Ma correlating with 3 distinguished zircon morphologies (Chapter 6). The absence of recrystallisation or inheritance suggests that these are 3 individual crystallisation events. These are interpreted as incremental pulses related to the progressive amalgamation of the Midyan and Hijaz microplates.
This syncollisional magmatism is spatially juxtaposed to the B’ir Umq Suture and seems highly unlikely to be directly involved in the collision of the Hijaz-Asir plates (Figure 8.3). As a consequence, it is interpreted that the 730Ma collision of the Midyan plate (Yanbu Suture) contained a very shallow subducting slab reaching inland into the Hijaz terrane. This collision with the Hijaz plate would continue to occur in pulses until 696Ma (Figure 8.5).
This process in this part of the Shield is not an isolated case, but is also duplicated by the Jar-Salajah Complex. This also contains 3 ages of 710.9±5Ma, 693.2±4.1Ma and 676.5.2±5Ma respectively (Chapter 6). In contrast to the Shufayyah Complex, the Jar Salajah cross-cuts the Yanbu Suture, thus directly dating the accretion of the Midyan and Hijaz plates. According to Johnson (2006), this suture zone was closed by 730-715Ma and marked by the Wask Ophiolite. The onset of subduction related magmatism <5Myr after this suture accretion suggests that the two plates were well and truly amalgamated (Figure 8.5). Interestingly, once again like the Shufayyah Complex, a similar trend in zircon morphology is apparent with initial stubby slightly distorted grains followed by elongate oscillatory zone zircons. This reinforces the possibility that initial collision between plates causes poorly zoned zircons, whilst the later are elongate and newly consolidated in the melt.
250 The Subh Suite felsic volcanism at 698.7±5.5Ma intrudes the Shufayyah Complex and is a new tightly constrained age that replaces the Rb-Sr whole rock age of 696-659Ma (Aleinikoff and Stoeser, 1989). This suite is thought to be the earliest known A-type in the Shield with the documentation of aegirine-bearing crystals in granitic units (Aleinikoff and Stoeser, 1989). However, this thesis cannot verify this claim with no characteristic A-type assemblages recorded (Appendix 1.3.2). The crystallisation age of Subh Suite is coherent with youngest recorded oscillatory zoned zircons from the Shufayyah Complex. Since this is only a 1-2Myr difference, it is interpreted that the Subh Suite is not an A-type suite. The Subh Suite intrudes into syncollisional subduction related melts which must certainly play a role in its formation (Chapter 7.2). It seems doubtful there is sufficient time for asthenospheric processes to occur between the formation of the Shufayyah Complex and arrival of the Subh Suite.
8.4 Post-Orogenic Magmatism (~636->600Ma).
This magmatic event plays a critical role in understanding the evolution of post- tectonic magmatism in the Arabian Shield. As previously discussed, many syncollisional phases contain multiple crystallisation ages and are deduced to involve incremental slab subduction. This phenomena is not limited to syncollisional processes, but is also observed in post-tectonic aegirine-bearing granitoids. These granitoids cross- cut or are juxtaposed to major suture zones such as the Nabitah Orogenic Belt and Halaban Suture in the eastern Shield (Figure 8.3). There is no doubt that these plutons mark the cessation of accretion, but display multiple crystallisation ages and are Hf isotopically discrete from western AAPG (Chapter 3.3). These are interpreted to be subduction related/MASH zone granitoids involving the gradual reduction in crustal components. These incremental rift stages play an important role in understanding the rise and fall of the Arabian Shield and will be discussed shortly.
A closer examination of the Nabitah Suture zone reveals some interesting observations. The accretion of this belt is terminated at ~640Ma with the first aegirine- bearing anorogenic magmatism recorded at 636.6±8.4Ma and 636±4Ma from the Kawr and Al Hafoor Suites respectively. However, the Kawr Suite continues to pulse again at
251 Figure 8.5 part1: A tectonic model representing the Midyan-Hijaz terranes corresponding with section A in Figure 8.3. The oldest unit sampled is the Al Ays Group (~740Ma), which is thought to represent frontal arc MORB like volcanism associated with the closure of the ocean basin between the two oceanic plates.
252 Figure 8.5 part2: A tectonic model representing the Midyan-Hijaz terranes corresponding with section A in Figure 8.3. The Shufayyah Complex marks the initial collision of the two plates at ~730Ma coinciding with the formation of the Yanbu ophiolitic suture. The geochemical parameters associated with this magmatism are discussed in Chapter 7.
253 Figure 8.5 part3: A tectonic model representing the Midyan-Hijaz terranes corresponding with section A in Figure 8.3. Continued incremental subduction of the Midyan plate produced multiple phases of granitic magmatism. This produced various syncollisional stages of the Shufayyah and Jar-Salajah Complexes as well as intermittent felsic volcanics of the Subh Suite. This magmatism continued until ~675Ma, which is the extent of the sampled units, but not the end of magmatic activity. The geochemical parameters associated with this magmatism are discussed in Chapter 7.
254 Figure 8.5 part4: A tectonic model representing the Midyan-Hijaz terranes corresponding with section A in Figure 8.3. Since no post-tectonic age units were sampled, the cross-section skips to the anorogenic phase. At ~600Ma, two A-type granitic suites appear to form, but from different geological processes. The slightly older of the two is the Admar Suite (~599Ma), which is situated midway between two suture zones. This is thought to have formed from a tear in the continued subducting slab of either the Midyan or Hijaz plates. Contrary to this is the Al Bad Granite Super Suite is isolated from accretion boundaries and is thought to represent lithospheric delamination (Chapter 7.6). The geochemical mechanisms associated with this magmatism are discussed in Chapters 7.4 and 7.5 respectively.
255 Figure 8.5 part5: A tectonic model representing the Midyan-Hijaz terranes corresponding with section A in Figure 8.3. The next phase of rift related magmatism occurs at ~600Ma with the imitation of Rithmah Complex gabbroic units. This magmatism is followed by the ~525Ma Mardabah Complex, which changes the previous regional unconformity boundary at ~542Ma. The small volume of magmatism suggests possible localised fault reactivation and is possibly linked to the final assembly of India and Africa (Chapter 8.6). The geochemical mechanisms associated with this magmatism are discussed in Chapter 7.4.
256 609.9±5.7Ma and 594.7±6.6Ma correlating with three distinct zircon morphologies (Chapter 6). An additional, more felsic, endmember of the Kawr Suite showed one age at 608Ma. The Wadbah Suite also shows 3 zircon groups and 3 distinct ages at 629.8±5.7Ma, 614±5.2Ma and 601.1±6.5Ma. The initiation of the isotopically differentiated Ibn Hashbal Suite at 617.6±5.2Ma marks the transition to within plate style granitoids (Chapter 3.3).
All suites associated with multiple crystallisation events are interpreted to be the result of incremental subduction related processes. Hafnium isotopes suggest a separation between the older units of the Kawr and Al Hafoor Suites and the younger granitoids within the Kawr and Ibn Hashbal Suites (Chapter 3.3). This isotopic spread occurs at ~618Ma with the Wadbah Suite forming a trail spreading over both crustal source arrays (Figure 8.7). This phenomenon is interpreted to be the gradual reduction of crustal components from the subducting plates underneath the Nabitah Belt.
Initially, the generation of the Nabitah post-orogenic magmatism may result from melting of the lower lithosphere and generation of a long-lived MASH zone (Smithies et al., 2011). The continued slab subduction down into the mantle may result in slab roll back at ~618Ma creating a tear in the slab (Chapter 7.3). This would allow influx of enriched, more juvenile mantle that undergoes decompression to produce perthitic endmembers towards the surface. This is summarised in Figure 8.4. Additionally, the Kawr Suite is documented at 650-620Ma (Johnson, 2006), encroaching into Nabitah Orogenesis which makes this scenario even more possible.
Slab tear is not limited to the Nabitah Orogenic Belt, but also observed in the Halaban Suture in the eastern margins of the Shield. The anorogenic Najirah Granitoid is isotopically similar to the Wadbah Suite (Chapter 3.3) containing 3 discrete ages of 631.4±9.1Ma, 606.5±6Ma and 584.4±8.8Ma (Chapter 6). The Hf data spread through both crustal arrays and more juvenile fields (Figure 8.7). This reinforces the possibility of initial collision followed by slab tear. The remainder of post-tectonic suites discussed in Chapter 3.2.2 are isotopically constrained to within plate style suites (Chapter 3.3).
Recorded incremental ages play an important role in understanding the rise and fall of the Shield. As discussed by Avigad and Gvirtzman (2009), the rise and fall of the
257 Arabian Shield through lithospheric delamination occurred over a ~40Myr window. Ordinarily, this may seem like a relative large window for A-type generation to occur. However, this is not an isolated case as discussed by Foden et al. (2002) who illustrate the Delamerian Orogeny, South Australia as a series of compression-extension processes producing A-type magmatism ranging from ~525-485Ma.
Incremental magmatism from ~636-600Ma in the Arabian Shield evolved in a similar manner. Subtle magmatic differences at ~618Ma indicate a change from subduction related samples to WPG classified suites resulting from slab tear underneath the Nabitah Belt (Chapter 7.3). This ~36Myr window of post-tectonic magmatism is separated into two small portions of ~10Myrs (initial pulses) and ~20Myrs (switch in mantle) respectively. Tectonically speaking, this seems acceptable for the rise and fall of the Arabian lithosphere. The <600Ma final assembly of Gondwanian fragments (Trompette, 1997; Johnson et al., 2011), relieved continental pressure and allowed western Shield lithospheric delamination processes to predominate. The slab roll back and tear of post-tectonic MASH zones is strictly associated with A-type magmatism and not syncollisional MASH zones. This is because continental pressure from colliding plates that creates syncollisional MASH zones is relieved, and post-tectonic extension is initiated. The cessation of orogenesis and initiation of extension causes the subducting slab to roll back and eventually tear allowing an influx of enriched mantle.
8.5 Anorogenic Magmatism (<600Ma).
This magmatic phase resembles the transition from subduction related environments to lithospheric delamination processes. These tightly age constrained perthitic suites are confined to back arc settings, isolated from mircoplate boundaries and classified as WPG suites. The switch in tectonic environment is marked by the subtle change in Hf isotopic signature indicating a reduction in crustal components (Chapter 3.3). It is interpreted that lithospheric delamination is not the result of slab roll back as illustrated by other perthitic suites (e.g. Kawr Suite), but the removal of the lithospheric root. Why this occurs precisely in certain locations and not others remains controversial (Stein and Goldstein, 1996; Be’eri-Shlevin et al., 2010), but in this chapter
258 it is believed to be caused by density differences at the base of the lithosphere. Geochemical evidence supporting this mechanism is discussed in Chapter 7.
Plutonism in the Midyan/Hijaz/Jiddah/Asir terranes is well documented as continuous accretionary cycles (Johnson, 2006). This thermally active lithosphere may be structurally weakened and, just like a piece of plastic that is reheated many times, eventually collapses. The cyclic deformation of ANS granitic lithosphere may give rise to high grade/dense metamorphic facies (e.g. granulite or eclogite, Chapter 1.5), which would eventually subside back into the mantle, allowing new material to rise and fill the void. Any additional strain placed on the Arabian Shield would certainly be transferred to the weakest parts of the crust. Conversely, any release in pressure i.e. cessation of accretion and final amalgamation of Gondwana fragments, would allow lithospheric extension to occur in this tectonically weakened lithosphere. This gradual release in continental pressure allowed the production of <600Ma WPG. This appears to correlate quite well with the initial phases of final western Gondwana assembly at ~600Ma proposed by Trompette (1997) and Johnson et al. (2011).
Aside from the Abanat Suite residing in the Ha’il terrane, the majority of AAPG samples are confined to the western Shield. The tectonically active Hijaz area displays an array of magmatic processes from 736-525Ma and creates a convenient discussion point for accretionary evolution. Syncollisional magmatism in this region is associated with microplate accretion and suture formation (736-676Ma) and a distinct ~75Myr window in this data set exists between accretion and the onset of ~600Ma post-tectonic WPG magmatism. Chapter 1.7, Figure 1.5 displays a high concentration of unassigned Neoproterozoic intrusives in this region. It is interpreted that these intrusives would likely fill the missing age gap and provide the complete transect from 730-<600Ma.
The initiation of lithospheric delamination in this area would not be unexpected. The intense volume of granitic intrusions preceding post-tectonic magmatism would likely create a thermally weakened zone with deformation in the lower crust. Eventually, the density would sufficiently increase to cause root removal back into the mantle. Details of the geochemical parameters are discussed in Chapter 7.6. It is interpreted that the northern Midyan Al Bad Granitoid Super Suite (597.4±4.8Ma, Chapter 3.2.1q) formed as a result of this process (Figure 8.6).
259 The similar age Admar Suite (599.2±3.8Ma, Chapter 3.2.1p) in the Hijaz terrane is closely related to microplate suture zones and may have resulted from a tear in the remnant slab. This is based on geochemical parameters discussed in Chapter 7.4. The Mardabah Complex also occurs here, but exhibits a date of 525.6±4.7Ma (Chapter 3.2.1s), which is now the youngest suite found so far in the Arabian Shield. This granitoid post dates the Cambrian regional unconformity at 542Ma and is thought to resemble localised extension associated with the final stage of Gondwana assembly at ~550-530Ma.
The occurrence of the Abanat Suite at 585Ma (Johnson, 2006) intrudes the Idah Suite. Both suites cover vast areas of the Ha’il and northern Afif terranes in almost the same spatial location. However, unlike the Idah Suite, the Abanat Suite is associated with economic REE deposits and shows a distinct transition to alkaline magmatism (Chapter 7). There is a ~20Myr window between the initiation of the Idah Suite and appearance of the Abanat Suite. This is interpreted as sufficient time for the subducting plate associated with the Nabitah Belt to subside back into the mantle. The emplacement of the Hadn Formation at 600Ma coincides with a transitional switch in magmatism. It is interpreted that the eastward subducting Hijaz plate under the Nabitah Belt created sufficient crustal depression (oceanic crustal thinning) by ~600Ma allowing the halide rich volcanic basin to form. Lithospheric delamination produced the upwelling of enriched mantle and late stage incorporation of the Hadn Formation, producing the REE Abanat Suite (Figure 8.6). The geochemical significance of this crustal contamination is explored further in Chapter 7.5.
Garnet-bearing leucogranites such as the Malik Granite in the Ad Dawadimi are the only crustally derived granites sampled in the Shield (Chapter 2). This has a cross- cutting relationship with the Idah Suite, so indirectly constrains the minimum age of the northern Ad Dawadimi accretion. The post-tectonic Idah Suite has a crystallisation age of 607.9±6.6Ma and is cross-cut by the Malik Granite at 599.6±5Ma (Figure 8.6). This suggests that minimum age of Ad Dawadimi microplate accretion must be ~600Ma because a new unit is formed. The geochemical parameters behind this coeval relationship are discussed in Chapter 7.7.
260 Figure 8.6 part1: A tectonic model representing the Hijaz-Afif terranes corresponding with section B in Figure 8.3. Island arc magmatism and fore arc basin development are the dominant processes occurring in the Shield >700Ma. These consist of the Al Ays and Siham Groups (~750-685Ma) on the western side of the Shield. The Nabitah Suture zone stitches the western and eastern side of the Shield initiating at ~700Ma with final assembly thought to be ~640Ma. No sampled units in the northern part of the Shield were obtained, so have been left out of the cross-section.
261 Figure 8.6 part2: A tectonic model representing the Hijaz-Afif terranes corresponding with section B in Figure 8.3. The Nabitah Suture zone stitches the western and eastern side of the Shield initiating at ~700Ma with final assembly thought to be ~640Ma. Widespread post-tectonic (~650-620Ma) amalgamation basins such as the Bani Ghayy and Murdama Groups are scattered across both the Afif, Ha’il and Ad Dawadimi terranes. The eastern side of the Shield has a continental affinity consisting of subducting Afif, Ad Dawadimi and Ar Ryan microplates. This continental subduction produces the first pulse of magmatism associated with the Najirah Granitoid and shortly after the more enriched Ar Ruwaydah Suite which intrudes it. The geochemical parameters associated with this magmatism are discussed in Chapter 7.
262 Figure 8.6 part3: A tectonic model representing the Hijaz-Afif and Ha’il terranes corresponding with section B in Figure 8.3. The continued subduction of the Afif continental plate produced another magmatic pulse at ~606Ma associated with the Najirah Granitoid. Slightly to the west, the subducting Hijaz plate underneath the Nabitah Suture initiates production of the vast Idah Suite batholith. This granitic unit extends into the Ha’il terrane and is likely to be diachronous, but is treated as one event. By this stage the eastern Shield is littered with post-tectonic magmatism and extensional basins. These two granitic units are associated with melting of the lower lithosphere and development of a MASH zone. The geochemical mechanisms are discussed further in Chapter 7.
263 Figure 8.6 part4: A tectonic model representing the Hijaz- Afif and Ha’il terranes corresponding with section B in Figure 8.3. The continued roll back of the Afif and Ad Dawadimi microplates develops a tear allowing the influx of enriched mantle (final pulse of the Najirah Granitoid at 585Ma). Localised crustal melting of the same MASH zone produces Malik Granitoid at 599Ma and intrudes the Idah Suite. The widespread 585Ma Abanat Suite, is a dominant economic batholith in both the Afif and Ha’il terranes. It is interpreted to be a product of lithospheric delamination and intrudes the Idah Suite. This is certainly the case for the Ha’il terrane in which the Abanat Suite is isolated from plate boundaries, but is also assumed for the extension into the Afif terrane. The geochemical mechanisms are discussed further in Chapter 7.
264 8.6 Evidence for Final Gondwana Assembly.
The development of 1200Ma rift and passive margins related to Rodinian supercontinent dismemberment sparked the initial opening of the Mozambique belt linking east and west parts of Gondwana (Meert, 2003; Collins and Pisarevsky, 2005; Li et al., 2008; Johnson et al., 2011). This north-south trending belt formed a series of arc accretions and continental fragments forming what is referred to as the East African Orogen (EAO). The Arabian-Nubian Shield (ANS) is composed of a series of young, juvenile terranes, which arguably form the best example of supercontinental detachment and amalgamation observed in Gondwana. This Arabian Shield is a product of EAO activity and indirectly mimics supercontinental cycles that formed Gondwana.
The generation of juvenile island arc magmatism in the western side of the Arabian Shield was the first substantial phase observed in reforming crustal blocks (e.g. India) that eventually form Gondwana. This ~900-750Ma event (Stern, 1994), but more recently ~900-650Ma (Figure 8.1), is reportedly the closure of the Mozambique Ocean which littered the western Shield with frontal arc magmatism. The production of the 867-829Ma Makkah Suite (Chapter 3.2.1a) in the Jeddah terrane is the oldest suite dated in this chapter. The slowly eastward migrating ocean plates of the EAO resulting from the closure of the Mozambique Ocean happened in distinct incremental pulses (Chapter 8.2). The appearance of ophiolitic suture zones between western terrane fragments produced an abrupt halt to island arc magmatism.
As discussed by Meert (2003), magmatism in the ANS from 750-630Ma marks the first stage of the east Africa and eastern Gondwana subduction related arcs. Locally, accretionary ophiolitic suture zones between western fragments and even more substantially the Nabitah Orogenic Belt, reflect this eastward movement of the EAO. Syncollisional magmatism in the north Shield at 736-676Ma (Shufayyah and Jar- Salajah Complexes, Chapters 3.2.1b and 3.2.1c) stitches the Midyan and Hijaz plates and reinforces the ~730-680Ma Yanbu and B’ir Umq Suture ages. The incremental syncollisional nature of these suites is consistent with the tectonic movements involving the northern part of the Mozambique Belt. As suggested by Trompette (1997) and Meert (2003) the African and South American continental fragments involved a series of continual subduction collisions from ~750-650Ma and amalgamated after this time. It is
265 interpreted that Arabian Shield syncollisional magmatism mimics these incremental subduction processes by the closure of ocean basins initiating at 736Ma and continuing through 716Ma, 710Ma, 695Ma, 693Ma, finally terminating at 676Ma (Chapters 3.2.1b and 3.2.1c).
The Nabitah Orogenic Belt is the largest complex structural zone in the Arabian Shield (Figure 8.3). This ~200km wide, north-south trending feature separates the eastern and western parts of the Shield, spreading from the Ha’il province in the north to the Asir terrane in the south. The age of this structure is diachronous along strike with initial northern accretions at ~700-680Ma with final southern assembly by 640Ma (Johnson, 2006). This process is thought to be the amalgamation of the western island arc terranes subducted under continental fragments to the east (Stoeser and Camp, 1985). Collins and Pisarevsky (2005) suggest that the collision of Azania with the Congo/Tanzania/Bangweulu block caused the termination of accretion/arc collision in the western ANS at ~630Ma (west of Afif).
The appearance of 636-597Ma aegirine post-tectonic magmatism intruding the Nabitah Orogenic Belt (Kawr, Wadbah, and Ibn Hashbal Suites) would reinforce this interpretation. It is suggested that sheer size of this orogenic belt resembles the final closure of the Mozambique Ocean, hence amalgamation of east Africa and eastern Gondwana. The northward drifting continental fragments of the Azania, Congo, Tanzania and Bangweulu blocks influenced the converging western plates creating an oblique style, diachronous accretion with the east (Collins and Pisarevsky 2005). The final accretion between drifting fragments was terminated at ~636Ma marked by the appearance of aegirine intrusions.
According to Collins and Pisarevsky (2005) and Johnson et al. (2011), subduction magmatism was still occurring until ~600Ma in the Ar Ryan terrane (east of Afif). This possibly correlates with the post-orogenic Najirah Granitoid and Ar Ruwaydah Suite associated with the Halaban Suture Zone in the Ad Dawadimi terrane (bordering Ar Ryan terrane). It is suggested that the Afif-Abas block consisting of Yemen, Somalia and Madagascar (Collins and Pisarevsky, 2005) collided with the eastern Arabian Shield. The appearance of the subduction related Najirah Granitoid (A- type MASH Zone, Chapter 7.3) marked the initiation of final collisions of the eastern
266 shield as magmatic pulsing beginning at ~631Ma (Chapter 6). Final amalgamation coincides with the switch in magmatism at ~612Ma (AAPG Ar Ruwaydah Suite), ~606Ma and ~584Ma (Najirah Granitoid; tear in subducting slab, see Chapter 7.3).
It is well documented that the occurrence of post-collisional A-type magmatism signals the end of the Wilson cycle (Bonin, 1990). The constraints on how these granitoids form are not discussed in this section, but in Chapter 7. Post-tectonic granitoids in the Shield are separated into two distinct groups: subduction related (<636>600Ma) and within plate related (<600Ma, Chapter 3.2). Both the western and eastern Shield contains the latter, with the former confined to the Nabitah and eastern Shield sutures (Chapters 8.4 and 8.5). It is interpreted in this Chapter that the suture related plutons, although post-tectonic, are in part subduction related (slab rollback/tear). By contrast, the anorogenic (<600Ma) are strictly within plate processes.
In terms of Gondwana assembly, although Island arc accretion had ceased in the western Shield, continued eastward subduction caused the melting of the lower crust underneath the Nabitah Belt. The generation of the long lived MASH zone (Smithies et al., 2011) allowed a continued pulsing of anorogenic magmatism until the occurrence of slab tear/roll back at 594 Ma (Chapter 8.4). This coincides with the appearance of lithospheric within plate magmatism in the Shield. The geochemical significance of the MASH zone and lithospheric process is discussed further in Chapters 7.3 and 7.6. These tectonic environments possibly correlate with Trompette (1997) and Li et al. (2008) who suggest that the South American and African western continental fragments were finally amalgamated at ~600Ma. This may have caused a switch to extensional environments as stress transference on the Arabian Shield was alleviated.
One of the most interesting discoveries is the dating of the previously unknown age Mardabah Complex. This olivine syenite (Appendix 1.3.4) resides in the Hijaz terrane (Figure 8.3) and had previously contained an assumed Ediacaran age determined by structural relationships (Johnson, 2006). However, this now contains a reliable U-Pb crystallisation age of 525.6±4.7Ma (n=17, MSWD=1.15, Chapter 3.2.1s). This age is incompatible with the assigned Ediacaran age and is significant for two reasons: 1) it post-dates the Cambrian regional unconformity at 542Ma, and 2) it is now the youngest recorded anorogenic magmatism in the Arabian-Nubian Shield. Johnson
267 (2006) provides an excellent lithostratigraphic spatial time plot summarising the Arabian Shield thus far.
The base Cambrian regional unconformity (542Ma) is a globally significant boundary. This unconformity in the ANS is marked by peneplain development and is indirectly dated by the absence of magmatism proceeding this date (Johnson, 2006). The U-Pb age of 525.6Ma recorded by Mardabah Complex zircons, suggest the local revised dating of this unconformity to 500Ma as indicated by Figure 8.2. This is not an isolated case, but 40Ar-39Ar dating of doleritic dykes from the Timna Igneous Complex (southern Israel) yielded a plateau age of 531.7±4.6Ma (Beyth and Heimann, 1999). These intrude the youngest Precambrian units in the northern Shield and are the only other documented case with a similar age. This suggests that magmatism continues into the Cambrian reinforcing the repositioning of the 542Ma unconformity. Beyth and Heimann, (1999) also suggest revised dating of this unconformity. Interestingly, the Timna dolerite is currently the youngest post-collisional magmatism in the ANS. The Mardabah Complex data in this chapter, although only marginally younger, is now the youngest recorded suite in the ANS. The youngest age estimates above the ~542Ma unconformity are ~560Ma (Khuls and Radwa Granitoid) and ~590-560Ma (Ediacaran basins), but many granitic suites remain unassigned (Johnson, 2006).
At a glance, the Mardabah Complex only appears to redefine post-tectonic extensional magmatism in the northern part of the Arabian Shield. A closer inspection on the 570-530Ma final Gondwana assembly (Meert, 2003; Collins and Pisarevsky, 2005; Li et al., 2008; Johnson et al., 2011) provides insight into the generation of these rift related granitoids. Major extensional transform faults such as the Najd and Ruwah systems scatter the northern Arabian Shield as late Precambrian (<600Ma) tectonic events (Stern, 1985). Dating of these shear zones remains difficult, but according to Meert (2003) reliable dates from Kusky and Matesh (1999) place the Najd system at 576.6±5.3Ma. The significance of major fault systems will become apparent shortly.
As mentioned above, the first stage of assembly between east Africa and eastern crustal blocks (e.g. India) occurs at ~750-620Ma (eventually forms Gondwana). The second significant continental collision event at 570-530Ma is split into two orogenic episodes, the Kunnga and Malagasy respectively (Collins and Pisarevsky, 2005). The
268 collision of Australia-east Antarctica-southern India-Sri Lanka-southern Madagascar and south east Africa constitutes the Kunnga Orogeny. More relevantly, the Malagasy Orogeny involves the impact of India with the already amalgamated African continent consisting of the Congo/Tanzania/Bangweulu block. The repercussions of this are observed in the northern EAO and consequently, the Arabian Shield. It is interpreted that the 525Ma anorogenic magmatism in the Hijaz terrane is a result of the reactivation of the Najd + other major fault systems. This would cause localised stress transferral and result in isolated extension events. Johnson et al. (2011) discuss this northern Shield fault system as a series of reactivated events that induce magmatism. It is suggested that the Mardabah Complex is a product of localised extension that induced melting of the upper lithosphere (Chapter 7.4).
It is well established that anorogenic magmatism marks the termination phases of continental assembly. The Arabian Shield has previously experienced a series of syncollisional and anorogenic phases from ~750-570Ma. This second magmatic event caused by the Malagasy Orogeny, produced the Mardabah Complex. This undeformed 525Ma age granitic suite is thought to indirectly help constrain the final stages of Gondwana collision. The effect of the 570-530Ma orogenic event appears to be absent in central Arabia with no deformed magmatism recorded. This is likely due to the isolation from tectonic activity. Stress transferral along reactivated Arabian faults produced the localised rift magmatism marking the termination of Gondwana assembly.
The small volume, isolated and rounded nature of Mardabah Complex like intrusions holds the key to discovering more post-collisional granitoids younger than 542Ma. As indicated by Chapter 1.7, Figure 1.5, the Arabian Shield contains numerous unassigned within plate granitic intrusions similar to the Mardabah Complex. Ediacaran suites such as the Abbasiyah Granodiorite, Uraynibi Syenogranitoid, Suwaylih Suite and Gharamil Monzogranitoid (Johnson, 2006) all share the common trait of being age indeterminate and isolated small volume intrusions. Similar to the Mardabah Complex, these are characteristically in the vicinity of major structural fault zones such as the Ruwah and Najd Fault zones. It would be expected that these granitoids are certainly <600Ma and more than likely <540Ma. The dating of these intrusions would constrain further the idea that final Gondwana assembly reactivated these faults producing localised rift magmatism.
269 8.7 Subtle changes in Homogeneous Juvenile Mantle Melts.
One of the most fascinating characteristics of the Arabian Shield is the continuous spectrum of the Wilson cycle illustrated from west to east, reflecting supercontinental amalgamation trends. The continuation of ~900Ma island arc magmatism in the west was interrupted by a series of 750-630Ma accretionary arc events that were finally cross-cut by <630Ma post-tectonic magmatism. One would assume that these discrete magmatic events would produce very distinctive mantle Hf isotopic signatures, particularly between syncollisional subduction related and post- tectonic extension related events. As discussed by Stern (1994) and Be’eri-Shlevin et al. (2010), this is not the case with many isotopic studies revealing a very juvenile (typically ɛHf > +5) homogeneous mantle. Despite the controversial enriched or depleted nature of this mantle, it is clear that all melts from this Shield data reinforce the term ‘most juvenile continental crust on Earth’ (Stern, 1994; Stoeser and Frost, 2006).
As observed in Figures 8.1 and 8.7, there is a clear separation in the data set presented in this thesis between 4 magmatic groups: island arc (867-829Ma), syncollisional (736-676Ma), post-tectonic (636-600Ma) and anorogenic (525Ma). These all typically range from ɛHf +5 to +12 with a slight syncollisional tail and large variation in the post-tectonic realm, which will be discussed shortly. Details on individual suites are described in Chapter 3.3. Overall, regardless of age, geochemical orientation or tectonic setting, Shield data records a series of juvenile crustal formation events in which the mantle repeatedly sources large volumes of crust for long periods of time. However, hidden behind this mantle homogeneity are subtle differences in crustal sources giving rise to a mixture of lithospheric processes.
One of the most obvious focal points from Figure 8.7 is the cluster of Hf values at ~600Ma. This area is a combination of east and west terrane subduction and within plate related granitoids. Highlighted in red, black and green are the eastern Shield granitoids (ESG), Nabitah Suture granitoids (NSG) and the western Shield within plate granitoids (WWPG) respectively. These constitute 19 analysed suites with the respective isotopic characteristics described in Chapter 3.3. Although these are all juvenile, there is a subtle change in Hf isotopic chemistry. WWPG are all <600Ma and display a tight isotopic range from ɛHf +7-+10. These are distinct from the isotopic
270 ranges of the ESG and NSG which convey ɛHf +4+11 and +4-+15 spread respectively. The dispersion of data between the ESP and NSG warrants further investigation using the <600Ma WWPG as a bench mark for lithospheric delamination processes.
It is well documented that the western Hijaz and Asir island arc terranes collided with the eastern Afif continental plate creating the ~200km wide Nabitah Orogenic Belt (Stoeser and Camp, 1985). Coincidentally, the anorogenic intrusions associated with the Nabitah Suture show the most isotopic variation and create a convenient focal point. The oldest sample dated in the Nabitah Suture is kw42 with a multi-crystallisation age of ~636-610-594Ma (Chapter 6) and contains a relatively tight ɛHf isotopic range from +4-+8 forming a complex fractionated granitic system (Chapters 2 and 4). The second sample kw51p has a distinct date at 608Ma (Chapter 3.2.1l). This exhibits a distinguished cluster from ɛHf +6 to +15, with some overlap with the older kw42. This elongate isotopic system is the basis for the following subtle discrimination between tectonic processes. The validity of separating units is reinforced in Figure 8.8, which illustrates two distinguished crustal arrays: 1) less juvenile melts (ɛHf <+5) displaying older crustal sources >1100Ma i.e. incorporation of reworked crust; 2) more juvenile melts (ɛNd >+5) displaying younger crustal sources <1100Ma i.e. more mantle like.
As indicated by Figure 8.7, the older Kawr Suite alongside the Al Hafoor (eastern margin of the Nabitah) and Al Khushaymiyah Suites (western margin of the Ad Dawadimi terranes) clearly form an isolated group from the remainder of the Hf isotopic data. This is attributed to the incorporation of older crustal material (separated by a dashed line) correlating with the isotopic tail of the syncollisional (~736-675Ma) subduction related magmatism. It is interpreted that these early stage NSG are the result of crustal contamination in a subduction style N-MORB MASH system (Chapter 7.3).
The Nd isotopic data of the above suites (Chapter 4.3) also appears to correlate with Khida crustal signatures.The Makkah Suite (867-829Ma) and Al Khushaymiyah Suite (601Ma) are also less juvenile than all other Arabian granitoids. It is suggested that the Paleoproterozoic Khida terrane was crustal source to these N-MORB like subduction magmas. The ~636Ma Kawr and Al Hafoor suites immediately follow the ~640Ma Nabitah Suture closure and are interpreted to be the initiation of lower crustal melting/contamination reflected in the less juvenile mantle composition (Figure 8.7).
271 Figure 8.7: ɛHf vs. 206Pb-238U age diagram illustrating the evolution of sampled units across the Arabian Shield. Hf data was processed using HfTrax software (Payne, 2010) and model ages calculated using the 176Lu decay constant of 1.87x10-11 (Scherer et al., 2001) and average 176Lu/177Hf crustal composition of 0.015 (Griffin et al., 2002). Mean crustal model ages of each suite are displayed, highlighting the minimum and maximum values (dashed lines). These indicate juvenile melts associated with crustal sources possibly related to Pan-African rifting (Chapter 8.7). All suites exhibit juvenile characteristics from a homogeneous mantle, but appear to show subtle isotopic variation within the eastern Shield granitoids (inset). This is interpreted to be a transition from suture related to within plate magmatism resulting in a decrease of crustal components with time. This is discussed in Chapter 7. The square inserts A, B, C and D are displayed in Figure 8.8.
272 The Nabitah Suture is considered to be the site of island arc terranes colliding with eastern continental crust (Stoeser and Camp, 1985). The correlation with NSG contamination appears to be consistent with syncollisional (western Shield island arc) magmatism placing doubt on young continental or island arc style contamination. The Al Khushaymiyah Suite is located west of the Halaban Suture in the continental Afif terrane and clearly deprived of island arc contamination yet produces a very similar cluster of data to the older NSG. It is therefore interpreted that the syncollisional, NSG and Al Khushaymiyah Suite are contaminated by Khida terrane continental style crust. The geochemistry is explored further in Chapter 7.2.
Other suture related granitoids include the Najirah Granitoid and Wadbah Suite, which are dated at 631-606-585Ma and 629-614-601Ma respectively (Chapters 3.2.1g and 3.2.1h). The Najirah Granitoid has a coeval relationship with the Nabitah Suture, but resides in the continental Ad Dawadimi terrane juxtaposed and intruding the Halaban Suture. In Figure 8.7, both suites display a somewhat elongate isotopic range from +4-+10, which is distributed over both parts of the dashed line. These suites are also interpreted to initially produce crustally contaminated subduction related melts at 630Ma, but then display a transition to the within plate realm. The age of this transition will be discussed shortly. The geographical separation of the two suites producing similar isotopic variation once again reinforces the plausibility of the contamination having crustal rather than island arc affinities. It is suggested that the crustal contamination of the Najirah Granitoid MASH zone may be the Afif-Abas block colliding with eastern Arabia.
There is a distinct isotopic change below the Nabitah Belt at ~618Ma with suites illustrating tightly constrained within plate style Hf isotopic affinities (Figure 8.7). The Kawr and Ibn Hashbal Suites confined to the Nabitah Orogenic Belt are both dated at ~618Ma. The remainder of the eastern suites (Ar Ruwaydah, Haml) and the crustal Malik Granitoid are all <618-600Ma and confined to the within plate realm. These all correlate with western Shield within plate (<600Ma) granitoids, both forming tightly constrained isotopic fields.
273 Figure 8.8 part1: ɛHf vs. 206Pb-238U age diagrams (Figure 8.7 sections A and B) illustrating the evolution of discrete magmatic events in the Arabian Shield. The Hf data was processed using HfTrax software (Payne, 2010) and model ages calculated using the 176Lu decay constant of 1.87x10-11 (Scherer et al., 2001) and an average 176Lu/177Hf crustal composition of 0.015 (Griffin et al., 2002). A) Juvenile island arc melts of the Jiddah Terrane. The maximum and minimum crustal model ages of the Makkah Suite are displayed. B) Syncollisional juvenile melts alongside the Makkah Suite crustal array (dashed blue). Note the large isotopic variation in some granitic units, possibly indicating a Rodinian crust source (Chapter 8.7).
274 Figure 8.8 part2: ɛHf vs. 206Pb-238U age diagrams (Figure 8.7 sections C and D) illustrating the evolution of discrete magmatic events in the Arabian Shield. The Hf data was processed using HfTrax software (Payne, 2010) and model ages calculated using the 176Lu decay constant of 1.87x10-11 (Scherer et al., 2001) and an average 176Lu/177Hf crustal composition of 0.015 (Griffin et al., 2002). C) Post tectonic suites show two crustal array groups, possibly coinciding with changing tectonic settings at 618Ma i.e. WPG extension (upper array) and continental- continental plates (lower array). D) Anorogenic within plate granitoid suites of the western Shield showing a somewhat homogeneous data spread. The tectonic implications are discussed in Chapter 7.
275 An interesting observation is the transition from subduction related crustally contaminated melts to within plate homogeneous melts at ~618Ma. The transition also occurs within a single suite, particularly those associated with the Nabitah Orogenic Belt. This phenomenon is attributed to the initiation of a lower crustal MASH zone followed by the gradual increase in juvenility (Hf increase) and finally slab tear. The geochemical significance is discussed further in Chapter 7.3. The ~618Ma transition to more juvenile phases correlates well with the 750-620Ma assembly between east Africa and eastern Gondwana (Meert, 2003). The accretionary cessation at 620Ma causes relaxation in the eastward migrating slab which eventually tears, allowing the influx of more juvenile magmatism to prevail. As suggested by Trompette (1997), final assembly phases between South America and African continents occurred at ~600Ma. This correlates remarkably well with the anorogenic <600Ma dated granitoids (Chapter 3.2.2) marking the onset of within plate lithospheric delamination both in the western and eastern Shield.
Apart from the Paleoproterozoic Khida terrane, Arabian Shield juvenile accreted terranes encompass ages no older than 900Ma, suggesting that the Shield was non- existent during the ~1200-950Ma Rodinian dismantlement. The Afif terrane (eastern Shield) poses one exception to this rule with the exposure of Paleoproterozoic (~1800- 1670Ma) granitoids (Chapter 1.7, Figure 1.5) known as the Khida sub terrane (Whitehouse et al., 2001). This will not be discussed in great detail here, but as described previously, it may be a source of crustal contamination. Collins and Pisarevsky (2005) describe this unit as forming the Afif-Abas block consisting of Yemen, Somalia, Madagascar and possibly southern India (Madurai Block). This unit is confined to eastern Arabia and with its exclusion, a maximum age of 900Ma exists in the Shield.
The examination of Hf isotope crustal source ages (Chapter 3.3) highlights an interesting field of suggested Pan-African related events. Figure 8.7 illustrates the crustal source ages of all suites that lie within 1200-950Ma, which possibly correlates with the break up of Rodinia. These are average ages, but all granitoids typically range from ~900-1100Ma (Appendix 4). Granitic suites such as the Al Khushaymiyah Suite reach 1350Ma. The depleted mantle source ages, as expected, are typically 50-100Ma younger than crustal source ages. One might suggest that these are just oceanic sources
276 ~200-300Myrs older than their subduction and not Pan-African derived at all. However, the high concentration of suites with ɛHf and ɛNd model ages of ~1000- 1100Ma suggests that this is a significant event, which conveniently correlates with Pan-African age rifting. It is therefore suggested that these suites are most likely associated with the opening of the Mozambique Ocean. One possible interpretation for their petrogenesis in the Arabian Shield is the gradual formation of the Congo-Saharan- South American continental fragments. This appears to correlate well with Li et al. (2008), who indicate the gradual appearance of the Saharan fragments attached to the Congo from 1100-1000Ma. This would provide the crustal contamination required by all 19 suites to produce almost inseparable isotopic juvenile melts.
8.8 Concluding Remarks
Petrographic constraints on 20 sampled geological granitoids allowed subdivision into metaluminous, peraluminous and peralkaline suites (Chapter 2). These granitoids were separated further into those derived from fractionation (island arc, syncollisional and Nabitah Suture intrusions) and non-fractionation (suture juxtaposed and within plate intrusions). Similar perthitic textures and mineral assemblages place doubt on the conventional A-type classification that incorporates all felsic endmembers clearly derived from different geographical settings.
U-Pb analysis of the same 20 granitoids separated these into island arc (867- 829Ma), syncollisional (<730-636Ma), post tectonic (<636-600Ma) and anorogenic (<600Ma) magmatic events (Chapter 3.2). These Shield terrane accretionary cycles (collision/subduction followed by extension) suggest Mozambique Ocean closure followed by Gondwana assembly. Hf isotopes revealed subtle changes in juvenile mantle between these magmatic events (Chapter 3.3). Isotopic trends indicated a slight decrease in juvenility between age groups (i.e. incorporation of granitic crust with younger suites), but the appearance of the Nabitah intrusions indicates a change in lithospheric process. This is thought to represent a tear in the subducting slab allowing enriched mantle influx. All granitic suite model ages range from ~900-1100Ma, which is suggestive of Pan-African derived magmatism.
277 Conventional geochemical separation of Arabian granitoids placed great strain on current A-type terminology, but was achieved through incompatible trace elements and isotope geochemistry (Chapter 4). Mafic REE showed contaminated MORB like signatures corresponding with IA+Syn, NHSG and POPG suites. Conversely, AAPG are enriched (OIB like) illustrating limited fractionation and contamination. Nd isotopic analysis revealed clear distinctions between NHSG mafics (less juvenile) and within AAPG suites (more juvenile). This suggested that not all A-type granitoids are derived from enriched mantle sources.
The obvious differing geochemical parameters between IA+Syn, NHSG, POPG and AAPG suites created the necessity to revise the mantle sources associated with A- type granitoids (Chapter 4.4). A new classification scheme (modified from Pearce et al. 1984a) was developed using incompatible elements Y and Nb. The terminology I-S-A and ferroan type was instead replaced by contaminated and enriched mantle granitoids. This successfully demonstrated the separation of not only older syncollisional from post-tectonic suites, but within plate and fractionated suture endmembers that bear similar mineralogy and geochemistry. Similar trends continued when utilising zircon chemistry (Chapter 5). These illustrated two trend lines: contaminated; and enriched mantle source behaviour. Post-tectonic NHSG discrete zircon morphologies reflect the transition from contaminated to enriched mantle sources, suggestive of slab tear and asthenospheric influx.
Closer examination of syncollisional and post-tectonic age suites revealed 3 discrete crystallisation ages and zircon morphologies within the same sample (Chapter 6). It is established that these are not related to machine bias, inheritance or metamorphism. The tectonic implication, particularly from undeformed post-tectonic A- types was 3 discrete magmatic pulses related to incremental subduction beneath orogenic belts.
Post-tectonic granitoids contain similar ages and geochemical parameters, but display subtle differences in mafic geochemistry, isotopic signatures and discrete age groups. Consequently, two petrogenetic mechanisms were developed (Chapter 7). Nabitah Suture post-orogenic granitoids are long lived magmatic events that possess initial contaminated geochemistry synonymous with slab melting. The generation of
278 lower crustal MASH zones creates magmatic pulsing below sutures and eventually tears allowing asthenospheric mantle (coinciding with younger aegirine-bearing granitoids) to recharge a depleted reservoir. Conversely, the appearance of anorogenic within plate granitoids is characterised by widespread, tightly constrained (<10Ma) magmatism that is geochemically enriched (OIB like), economic and symbolic of lithospheric delamination and asthenospheric upwelling.
Arabian Shield petrogenetic models are summarised in Chapter 8 alongside their tectonic implications in relation to final Gondwana assembly. Overall, these granitoids mark accretionary cycles initiated from Rodinian dismantlement (Hf isotopic crustal source ages), Mozambique Ocean closure (island arc-syncollisional ages) and final amalgamation (post-tectonic ages). Final phase A-types are initiated with non- economic slab tear (orogenic termination) and are eventually followed by economic lithospheric delamination. The identification of magmatism recorded at 525Ma (Najd fault reactivation) is now the youngest granitoid found so far in the Arabian-Nubian Shield. This warrants revised dating of the regional unconformity at 542Ma and possibly correlates with the Malagasy/Kunnga Orogen (India-EOA collision) during the final stages of assembly.
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Whitehouse, M.J, Stoeser, D.B. and Stacey, J.S. (2001). The Khida terrane-geochronological and isotopic evidence for Paleoproterozoic and Achaean crust in the eastern Arabian Shield of Saudi Arabia. Gondwana Research 4, 200-202.
Williams, I.S. (1992). Some observations on the use of zircon U-Pb geochronology in the study of granitic rocks. Transactions of the Royal Society Edinburgh: Earth Sciences 83, 447-458.
Woodhead, J., Hergt, J., Shelley, M., Eggins, S. and Kemp, R. (2004). Zircon Hf-isotope analysis with an excimer laser, depth profiling, ablation of complex geometries, and concomitant age estimation. Chemical Geology 209, 121-135.
Woodhead, J.D. and Hergt, J.M. (2005). A Preliminary Appraisal of Seven Natural Zircon Materials for In Situ Hf Isotope Determination. Geostandards and Geoanalytical Research 29, 183-195.
289 Appendix a: Analytical Techniques
290 a1: U-Pb Geochronology.
Whole rock samples were prepared by the removal of weathered material followed by the crushing/milling of samples into medium grade powder. This was sieved using 75µm and 425µm mesh with collection of the >75µm-<425µm fraction. The zircon bearing concentrate was hand panned and passed through methylene iodide heavy liquid separation to isolate minerals with a density greater than 3.3gcm-3. This separate was then funnelled through a Franz magnetic separator (~0.6nT) before zircons in the remaining fraction were hand picked and mounted in epoxy resin.
A Phillips Xl20 scanning electron microscope with an attached Gatan Cathode Luminescence detector (Adelaide Microscopy) was used to indentify zonation within the polished carbon coated zircon crystals. An accelerating voltage of 12-15 keV with a spot size of 6-8v and a magnification of 200-500 times were the typical settings used to obtain backscatter and cathodoluminescence images of the individual grains (see Appendix 3).
U-Pb analysis was preformed by Laser Ablation Inductively Coupled Mass Spectrometry (LA-ICPMS) and was carried out on an Agilent 7500cs ICPMS coupled with a New Wave 213 nm Nd-YAG laser (Adelaide Microscopy). Calibration of the LA-ICPMS involved analysing standard reference material NIST 610, achieving maximum sensitivity (PA factor) for 206Pb and 238U. Individual zircon grains, typically greater than 100µm, were ablated in a helium atmosphere ablation cell, using a beam diameter of 30-40μm, frequency of 5 Hz and a laser intensity of 75%. Helium is used as the carrier gas to optimise transportation of ablated material and is mixed with argon (stabilisation) prior to entering the ICP detector.
Ablation and machine U-Pb isotope fractionation was corrected using the GEMOC GJ-1 standard (Jackson et al., 2004) and internal accuracy was checked using the Plesovice standard (Slama et al., 2008). A procedural repetition known as ‘block’ consisted of 3 GJ, 2 Plesovice, 10-12 unknowns and finally 2 GJ values with the standard GJ values used to linear fit the unknown values. Data acquisition involved 30 seconds of background measurement, 10 seconds of beam stabilisation and finally 60 seconds of sample ablation. Stable isotope signals were selected for age calculations
291 using Glitter software (Van Achterbergh et al., 2001). Concordia diagrams and probability distribution curves were constructed using the Isoplot macro (Ludwig, 2000). For zircons yielding an age <1 Ga the 206Pb-238U age was used and a concordancy calculated by dividing the 206Pb-238U by 207Pb-235U. All U-Pb geochronology is displayed in Appendix 2.
a2: Zircon Hf Isotopes.
Following U-Pb zircon geochronology, Lu/Hf isotopic analysis on the same granitic suites was conducted using Laser Ablation Multi Collector Inductively Coupled Mass Spectrometry (LA-MC-ICPMS) at the Waite Campus (CSIRO), South Australia. Individual zircon grains (>100µm) with greater than 90% 206Pb-238U/207Pb-235U concordance were analysed by a 50µm laser spot as close as possible to the U/Pb LA- ICPMS pit. The Al Hafoor Suite, Najirah Granite, Haml Suite, Al Khushaymiyah Suite and Malik Granite are exceptions with concordance ranging from the mid to high 80 percentile. However, these A-types exhibit low REE, so are considered valid Hf data values. The Lu/Hf spot locations of all 19 granitic suites are displayed in Appendix 4.
Similar to U-Pb geochronology, zircon grains were ablated in a helium atmosphere, which is mixed prior to entering the ablation cell. This ablation was undertaken with a New Wave UP-193 Excimer Laser (193nm) using a 4ns pulse length, intensity of ~10J/cm2 and a frequency of 5Hz. Lu/Hf measurements were conducted using a Thermo-Scientific Neptune Multicollector ICPMS equipped with Faraday detectors and 1012Ω amplifiers. Specific integration and idle times of Hf-Lu-Yb-Gd-Dy- Ho-Er isotopes is described in detail by Payne (2010). Prior to ablation sessions, calibration of the multicollector involved using JMC475 Hf and AMES Hf solutions. Machine accuracy was monitored by a combination of MudTank (n=19) and Plesovice (n=38) reference standards. These standards preceded any ablation of sampled zircon grains and were used intermittently when sample change was required. These are displayed in Appendix 4.
Hf Mass bias was corrected using an exponential fractionation law with a stable 179Hf/177Hf ratio of 0.7325. Yb and Lu isobaric interferences were corrected
292 adopting the methods of Woodhead et al. (2004). 176Yb interference on 176Hf was corrected by direct measurement of Yb fractionation (171Yb/173Yb) using Yb isotopic values of Segal et al. (2003). Validation of these values was determined by analysing JMC 475 Hf solutions doped with varying levels of Yb with interferences up to 176Yb/177Hf= ~0.5. Assuming a similar mass bias behaviour as Yb, Lu isobaric interference on 176Hf was corrected using a 176Lu/175Lu ratio of 0.02655 (Vervoort et al., 2004). Raw 176Lu/177Hf values were used to calculate 176Hf/177Hf model values (including initial Hf and ɛHf) based on the 176Lu decay constant 1.87 x 10-11 after Scherer et al., (2001). These parameters together with 206Pb-238U absolute age values are used to calculate TDM and TDM crust ages following the methods of Griffin et al. (2002), assuming an average crustal composition of 176Lu/177Hf=0.015. These values are displayed in Appendix4.
a3: Major and Trace Element Geochemistry.
All 137 samples collected and catalogued in Appendix 1 were cleaned of weathered material and a fraction was crushed into chip like fragments between iron jaws. This coarse grade material was then ring milled between tungsten carbide plates until a talc like consistency was achieved. This ensured an accurate representation of the bulk composition of the sample (granules produce inaccurate X-ray trace element analysis). Milling between tungsten carbide plates also eliminates the contamination of alloys such as Ni, Cr, Mo, and V associated with steel and iron. All 137 major and trace element analyses are presented in Appendix 5.
Major elemental analysis (SiO2, MgO, Fe2O3T, MnO, CaO, TiO2, Na2O, K2O and P2O5) was prepared by creating a fused glass disk. Approximately 2-3 g of milled dry sample was allocated into a clean vial and placed in an oven (1100C) for 24 hrs to remove any absorbed moisture. This was then weighed in an alumina crucible and ignited for 24 hrs in a 9600C furnace to yield the loss on ignition (LOI) values (organics + volatile materials in crystal structure). A nominal 1 g of the ignited sample was accurately weighed along with 4g of flux (type 12:22, comprising 35.3% lithium tetraborate and 64.7% lithium metaborate), which lowers the melting point of the powdered silicate sample. This sample-flux mixture was fused in a Pt-Au crucible using
293 a propane-oxygen flame at ~11500C. The molten sample was cast into a glass disk Pt- Au mould.
Trace element analysis (Zr, Nb, Y, Sr, Rb, U, Th, Pb, Ga, Zn, Cu, Ni, Ba, Sc, Co, V, Ce, Nd, La and Cr) involved the construction of a pressed pellet. Approximately 5-10g of milled powder was fused with 1-2mm of binding agent (Poly Vinyl Alcohol). This mixture was then placed into a clean metal cylinder mould and pressed with a manual jack (4 psi). This pressed disk was allowed to dry in air for 24hrs and prior to analysis, was dried further for 1-2 hrs in a 600C oven to ensure the pellet was completely dry.
Both major and trace element analysis was preformed at the University of Adelaide, Geology Departments, using a Phillips PW1480 X-ray spectrometer. This instrument is equipped with both a Sc-Mo dual anode tube and an Au tube. Major elements were analysed using the Sc-Mo tube operated at 40kV, 75mA. The program was calibrated against international and local standard reference materials BHVO- 1/BCR-1 (USGS) and TASBAS (Adelaide University). The values are expressed as oxides (includes organic material present) and the total iron content (ferrous and ferric components). Trace elements were analysed using both the Sc-Mo tube (higher voltages) and the Au tube operated at 50kV, 40mA. However, several calibration programs were used with up to 30 standard reference materials. Matrix corrections were made using either the Compton Scatter peak, or mass absorption coefficients calculated from the major element data. These results are presented as parts per million (ppm) with the calibration assuming levels of 1-2000ppm. Negative values generated by interference (overlapping element peak/background) and X-ray detection limit (outside sigma confidence criteria) are presented as zero values. The accuracy and precision of the XRF warrants the decimal place to be retained only for values <10ppm.
a4: Rare Earth Element Geochemistry.
Standard XRF analytical techniques encounter limitations with element concentrations at sub parts per million (ppm) and as a consequence remain undetectable.
294 Solution Inductively Coupled Plasma Mass Spectrometry (ICPMS) was used to determine Be, Cs, Dy, Eu, Hf, Sm, Yb, Er, Gd, Ho, Lu, Pr, Ta, Tb, Mo concentrations on all 137 samples analysed by XRF. These are displayed in Appendix 5.
A nominal 100mg of milled sample powder was accurately weighed into clean (standard series of nitric and hydrochloric acid washes) Teflon bombs. The sample was then treated with 4ml of single-distilled 50% HF and 2ml of single-distilled 7M HNO3. This was placed on a 140 0C hot plate overnight to facilitate the dissolution of silicate mineral phases. The dissolved powder was then allowed to evaporate to dryness with the periodic addition of 7M HNO3 acid to prevent the formation of insoluble fluorides. Dry residue was again redissolved in 4ml of single-distilled 50% HF and 2ml single distilled 7M HNO3. The Teflon bombs were sealed inside high pressure steel cylinders and placed into a 1900C oven for 120 hours. This was again allowed to evaporate to dryness with the periodic addition of 7M HNO3. Finally, the sample was redissolved in 6ml of single-distilled 6M HCl and placed back into the pressure oven at 1500C for 24 hours. This is followed by a final evaporation to dryness stage. The switch in acid types ensures element compounds insoluble in nitric phases are reabsorbed in the final hydrochloric phase.
The final residue was dissolved in 1.5ml of 7M HNO3 and centrifuged at 13,200 rpm for 10 minutes to remove any remaining insoluble material. A sample aliquot ranging between 0.17-0.22ml (depends on element concentration) was extracted and accurately weighted into clean 5ml polyethylene tubes. The remaining 5ml volume was complemented with deionised water. This procedure yielded a dilution factor typically ranging between 300-400 times e.g. 0.1g (powder) dissolved in 1.5ml nitric acid =15x dilution; 0.1788ml (aliquot) dissolved in 4.8481ml H2O gives dilution factor of 27.11 and a total dilution=406 times.
The sample solutions were analysed at Adelaide Microscopy using an Agilent 7500 solution ICPMS. Calibration was achieved by external standardisation with signal intensities of all isotopes measured in blank as well as artificial solutions of known concentration i.e. 500, 200, 100, 50, 10 and 1ppb. To check for machine reliability this was determined before any unknown analysis and repeated on termination. This created a linear relationship between the blank and corrected standards (diagram of signal
295 intensity vs. concentration) and was used to establish a calibration curve. Element raw counts per second were converted to concentration (ppb) through fitting the unknown data points to the established calibration curve. Instrument drift and matrix effects (includes isobaric, molecular, charged ion interferences) were corrected by using a 103Rh-115In solution. These non-interfered, mono-isotopic isotopes are used as the internal standardisation (difference from 100% Rh-In recovery) and corrections are applied to the raw counts per second of the unknown sample.
Procedural blanks and standard reference material G-2, GPS-2 and BCR2 (USGS) were also prepared in an identical manner to gauge procedure and machine accuracy (Appendix 5). Concentrations of elements in unknown samples were cross- examined with XRF trace elements to determine reliability. Particular interest was paid to Zr because zircon is notoriously difficult to dissolve. Rare Earth Elements in granitoid standard reference materials high in zirconium (G-2, GSP2) were used as a monitor for complete dissolution. As shown in Appendix 5 these were deemed to be within acceptable error. It is therefore confidently assumed that REE in the unknown Saudi Arabian granitoid samples are the correct values.
a5: Ferrous Iron Chemistry.
Conventional whole rock XRF or ICPMS elemental analysis does not discriminate between naturally occurring iron (Fe2+ and Fe3+) oxidation states in rocks and minerals. Instead, the total iron content is displayed as either FeO (Fe2+) or more 3+ commonly Fe2O3 (Fe ), which is the more oxidised form of iron. As illustrated in
Appendix 5, XRF analysis assigned Fe2O3 (Total) to all 137 samples (powder ignited- oxidised in furnace). The separation of ferric and ferrous components is necessary to help discriminate highly fractionated and homogenous granitic suites (Chapter 4). Ferrous iron determination was conducted on all 137 samples and is displayed in Appendix 5.
The determination of ferrous (FeO) iron content was achievable through a wet chemical procedure described in Sossi et al. (2012). Milled powder weights were induced by gauging the maximum FeO wt% content in a given sample. As illustrated in
296 Appendix 5, mafic samples that contained a high wt% of Fe2O3T (10-15wt%) required
~20-25mg of powder. Conversely, felsic samples that contained <1wt% Fe2O3T needed ~100mg of powder. This method is discussed in Sossi et al. (2012). To avoid metallic contamination, all sample powders were accurately weighed (5 decimals) on certified weighing paper and transferred to platinum crucibles. All 137 samples were analysed with 3 samples analysed at any given time. The 4th crucible was permanently left as a blank as this procedure relies on the titration of a blank solution (no FeO) treated with the same volume of oxidising agents as an unknown sample.
Whole rock powders were dissolved with two strong acids: 2ml single distilled
50wt% HF and 4ml of H2SO4. To act as the oxidising agent, 200 µl of 0.1963M ammonium metavadanate (NH4VO3) was also added. Crucibles were heated for 10 minutes on a 3500C hotplate to ensure complete dissolution. After cooling briefly, an 2+ 3+ additional 4ml of H2SO4 was added. This process oxidises all Fe in the sample to Fe and simultaneously all V4+ to V5+. Samples that contained a high % of iron emitted a blue coloured solution. Most granitoid samples remained a yellowish colour (sulphuric acid) indicative of low iron content. An inert universal indicator (N-phenyl anthranilic acid in weak Na2CO3) was added before titration (~5 drops sufficient to turn the solution purple). This solution was titrated in Teflon beakers with 0.00164459M
(accurately produced, Sossi et al., 2012) ammonium ferrous sulphate [(NH4)
2SO4.FeSO4.6H2O] which is another oxidising agent. The agent was slowly added one drop at a time until the first appearance of a green/brown solution. This colour change indicated all remaining V4+ in solution was oxidised to V5+. The titre value recorded is reflective of the FeO content in the sample i.e. high wt% FeO = large amount of initial V4+ to V5+ = small amount of titant needed for final reaction.
The importance of running the blank solution becomes imperative in the calculation of ferrous (FeO) and ferric (Fe2O3) components. The following equations are obtained from Sossi et al. (2012). The calculation of FeO wt % preformed on all 137 samples is as follows:
[(blank titre volume – sample titre volume) x (molarity of (NH4) 2SO4.FeSO4.6H2O) x (molar mass FeO)] *100% Sample Mass (mg)
297 The calculation of Fe2O3 wt % preformed on all 137 samples is as follows:
[(XRF Fe2O3T wt% / molar mass Fe2O3)*2 – (FeO wt % / molar mass FeO) /2)] * molar mass Fe2O3
To gauge procedure reliability the in house standard TASBAS (12.71wt%
Fe2O3T) was analysed. A total of 30 TASBAS standards were measured producing an average of 9.34 wt% FeO and 2.33 wt% Fe2O3 (Appendix 5). Some samples were also randomly repeated, particularly with the initiation of a new solution batch and showed <0.5% variation. This suggests that all 137 data points from the Arabian Shield are confidently reliable. It is noted that the sum of the FeO + Fe2O3 components does not exactly replicate the XRF Fe2O3T. This is possibly the result of the following: solution is lost in transferral between platinum and Teflon equipment, hydrous silicate minerals in sample are easily oxidised in air and Fe2+ is less stable than V4+ in hot acid solutions causing accidental oxidation (reduction in V5+ to V4+). In any case, the error associated with this titration procedure is at most a few %, thus rendering the FeO calculation reliable.
a6: Isotope Geochemistry.
Whole rock neodymium (Nd), samarium (Sm) and strontium (Sr) was preformed on 21 granitoid samples that had previously been petrographically interpreted, age dated and analysed for Hf isotopes (Chapters 2 and 3). An additional 10 country rocks and mafic autoliths were also analysed (Appendix 6).
The accuracy and precision of Thermal Ionisation Mass Spectrometry (TIMS) created the necessity to thoroughly clean Teflon vials/bombs associated with isotopic - analysis. A standard cleaning procedure involved: 24 hours submerged in 6M HNO3 heated to 2500C, followed by 6M HCl and finally deionised water. An additional 2ml of single distilled 6M HCL was placed into each vial and heated at 1200C overnight (capped). Although this process is time consuming, it ensured the removal of any soluble nitrate (organics) and/or chloride compounds (trace elements) that effect measured isotopic ratios.
298 Sample powder weight (g) was calculated based on a nominal 2µg of Nd (optimum TIMS accuracy and recovery value) and its corresponding Nd XRF concentration (ppm). The division of 2 by the Nd (ppm) yields a calculated weight that requires a minimum of 0.05g to precisely measure the isotopic Nd/Sm ratios. Isotope dilution mass spectrometry was determined by the addition of a nominal 0.4g of 150Nd/147Sm enriched spike. This allowed the concentration of Sm/Nd (µgg-1), hence the correction factor for the measured 143Nd/144Nd and 147Sm/149Sm isotopic ratios to be determined. Samples that contained <0.05g calculated weight were adjusted accordingly, hence also the amount of spike added to the sample. The addition of a strontium spike (~0.12g) allowed 87Sr/86Sr to be simultaneously determined. All milled powder and spike weights were accurately recorded (5 decimal places) on a Mettler- Toledo AT201 balance and are displayed in Appendix 6.
Depending on the calculated weight, 50-150mg of sample was placed into a clean Teflon bomb and treated with 4ml of single-distilled 50% HF and 2ml of single- 0 distilled 7M HNO3. This was placed on a 140 C hot plate overnight to facilitate the dissolution of silicate mineral phases. The dissolved powder was then allowed to evaporate to dryness with the periodic addition of 7M HNO3 acid to prevent the formation of insoluble fluorides. Dry residue was again redissolved in 4ml of single- distilled 50% HF and 2ml single distilled 7M HNO3. The Teflon bombs were sealed inside high pressure steel cylinders and placed into a 1900C oven for 120 hours. This was again allowed to evaporate to dryness with the periodic addition of 7M HNO3. Finally, the sample was redissolved in 6ml of single-distilled 6M HCl and placed back into the pressure oven at 1500C for 24 hours. This is followed by a final evaporation to dryness stage. The switch in acid types ensures element compounds insoluble in nitric phases are reabsorbed in the final hydrochloric phase.
The final residue was dissolved in 1.5ml of 6M HCl and centrifuged at 13,200 rpm for 10min to remove any remaining insoluble material. A 1ml aliquot was then passed through a two stage dilute HCl cation exchange hydrogen-diethyl-hexyl- phosphate reverse chromatography procedure. The removal of unwanted major and trace elements was achieved by using Biorad Polyprep columns. The 87Sr aliquot was passed through a second time to reduce 87Rb, which interferes with the measured ratio. The isolation of Sm from Nd involved the use of HDEHP impregnated Teflon-powder
299 columns and increased HCl concentration. Procedural blanks and standard reference materials G-2 (USGS) were also prepared in an identical manner to gauge procedure and machine accuracy (Appendix 6).
All Sr, Nd and Sm isotopes were measured at the University of Adelaide using a Finnigan MAT262 thermal ionisation mass spectrometer (TIMS). Dried sample was dissolved in 1µl of Bircks ionisation enhancing solution (TaO5+dilute H3PO4) and placed onto heated (~1-1.2 amp) degassed Rhenium-Tantalum filaments. Nd/Sm analysis involved double filaments with the sample loaded onto the Rhenium side. Conversely, Sr utilised single tantalum filaments with the exception of some samples containing with <2g of Sr (powder weight multiplied by XRF Sr value).
Procedural blanks and internal standards (G-2, JNdi1 and SRM987) were analysed prior to sample analysis to gauge machine accuracy and precision. These are summarised in Appendix 6. 150Nd/144Nd was measured to calculate the Nd concentration (µgg-1) in the sample, hence the amount of spike. This is then applied as the correction on the measured 143Nd/144Nd and yields the unmixed 143Nd/144Nd values. This multi-dynamic process consisted of a final value derived from 10 blocks of data (100 values with 2σ test) with a typical 144Nd ion beam measuring 1000mV.
All procedural blanks registered <100pg Nd, thus showed negligible contamination. Similarly, 147Sm/149Sm was used to measure and calculate the Sm concentration in the sample. 152Sm/149Sm was measured to correct for fractionation which naturally occurs in the heated instrument. The ionisation beam for 147Sm was typically 300-500mV and procedural blanks showed <20pg of Sm. The final value was derived from a static measurement of 20 values. 87Sr/86Sr analysis also involved the measurement of 100 data points. Typical 88Sr ionisation beams measured 2000mV and procedural blanks registered negligible <850pg Sr values. All isotopic values are displayed in Appendix 6.
The analysed granitic suites, mafic autoliths and country rocks all yield reliable unmixed 143Nd/144Nd and 147Sm/144Nd isotopic ratios and Nd/Sm concentrations (µgg-1). Present day (t=0) ɛNd values were obtained using 143Nd/144Nd CHUR (t=0): 0.512638; 147Sm/144Nd (t=0): 0.1966; 143/144Nd DM (t=0): 0.513150 and 147Sm/144Nd DM (t=0):
300 0.2145 ratios taken from Goldstein et al (1984). Model ages (T) are calculated based on these ratio values. Granitic units are assigned ages that have been directly dated using U-Pb zircon geochronology (Chapter 3). Although not directly dated, parent mafic autoliths are assumed to be the same age as the granitic product in the same suite. All remaining suites not directly dated are assigned published age values obtained from Johnson (2006). Model age values are exhibited in Appendix 6.
a7: Zircon Trace Element Geochemistry.
Following U-Pb geochronology and Hf isotopic investigation (Chapter 3) zircons were selected for trace element analysis based on a) the availability/size of zircon surface area b) compositional zoning and c) concordancy. A total of 19 suites were analyses and are displayed in Appendix 7.
LA-ICPMS was carried out at Adelaide Microscopy using an Agilent 7500cs ICPMS coupled with a New Wave 213 nm Nd-YAG laser. Calibration of the instrument involved analysing standard reference material NIST 610, achieving maximum sensitivity (PA factor) for elements listed in Appendix 7. Special attention was paid to the REE confined to zircon such as Hf, Yb, Lu, La, Ce, Sm, Nd, which often needed increased laser intensity and/or frequency to achieve a recordable PA factor. Individual zircon grains, typically greater than 100µm, were ablated in a helium atmosphere ablation cell, using a beam diameter of 75μm, frequency of 5 Hz and a laser intensity of 75%. Helium is used as the carrier gas to optimise transportation of ablated material and is mixed with argon (stabilisation) prior to entering the ICP detector.
Ablation and machine isotope fractionation was corrected using the internationally recognised standard nist610 and internal accuracy was checked using nist612 standard. A procedural repetition known as ‘block’ consisted of 4 nist610, 2 nist612, 10-12 unknowns and finally 2 nist610 values. These nist610 values are used to convert the counts per second of the unknown samples to concentration (ppm) by linear modelling. Data acquisition involved 30 seconds of background measurement, 10 seconds of beam stabilisation and finally 60 seconds of sample ablation. Stable isotope
301 signals were selected and processed using GLITTER software (Van Achterbergh et al. 2001).
The construction of the calibration line for both nist610/612 and the unknown zircon grains required an element to be selected as the standard. The chemical formula for Zircon is ZrSiO4 [SiO2=31.57% and ZrO2=58.27%] and ideally a microprobe should be used to accurately determine the wt% of elements in the unknown zircon grain for every spot of interest. However, this was felt unnecessary because SiO2 is assumed to be homogenous across all grains and any variation in SiO2 would not significantly effect bulk REE patterns of interest (probably <5%). As a consequence, Si29 was the selected element to use for the calibration standard and assigned the value of 31.57 wt% for every analysis. This was used over Zr90 because any variation caused by ablating anomalous material e.g. apatite is easily identified using Si29.
The compositional zonation observed in zircon grains makes the processing of analyses difficult. Even within a given suite, zircon REE elements may vary from <100- <5000ppm. A block of 10-12 unknown zircon analyses were culled using the major elements Na23, Mg24, Al27, P31, K39, Ca43, Ti43 and Fe57 as a monitor for accidental mineral inclusion ablation. For example some analyses contained >10000ppm P31 and Ca43 with elevated REE values (synonymous with apatite), so as a result were discarded. This was reflected in the isotopic signal, which displayed sharp peaks and/or troughs disrupting a stable signal. Obvious discolourations and cracks were avoided with each analysis corresponding to the cathodoluminescence images illustrated in Appendix 3.
302 Appendix 1: Sample Catalogue from the Arabian Shield
303 Appendix 1.1: Midyan terrane samples collected from the Arabian Shield, Saudi Arabia (see Chapter 2.4, Figure 2.10 and Appendix 1.1.1 for location in the Shield and petrography respectively).
Sample Shield Published Geochronological Age Geological Map Unit Latitude Longitude Rock Type Field Mineralogy + Observations Name Terrane (Johnson, 2006) abg 171 280 44'29.40'' N 350 20'00.99'' E Alkali-Granite Medium-coarse grained pink/grey granite consisting almost entirely of abg 172 280 44'28.46'' N 350 20'08.51'' E Alkali-Granite pink alkali-feldspar and quartz with minor biotite and possibly purple abg 173 Al Bad Granite Super 280 44'16.92'' N 350 19'58.10'' E Alkali-Granite flourine. These are exposed by Midyan terrane mountain ranges (Lawz It has been dated with U-Pb in Midyan abg 178 Suite (abg) 280 44'24.70'' N 350 20'04.36'' E Alkali-Granite Mt.) with sharp discordant contacts in the northwestern part of the zircon (577Ma) and a Rb-Sr 0 0 abg 179 28 44'32.20'' N 35 20'12.32'' E Alkali-Granite Shield. Contact zones are often marked by mafic dykes and the Isochron (586Ma). 0 0 abg 180 28 44'18.58'' N 35 20'02.94'' E Alkali-Granite granites often contain country rock xenoliths.
Appendix 1.2: Jiddah terrane samples collected from the Arabian Shield, Saudi Arabia (see Chapter 2.4, Figure 2.10 and Chapter 2.3.1 for location in the Shield and petrography respectively).
Sample Shield Published Geochronological Age Geological Map Unit Latitude Longitude Rock Type Field Mineralogy + Observations Name Terrane (Johnson, 2006) dm01a 210 21'36.45'' N 400 15'44.86'' E Gabbro-Diorite Medium-fine grained grey/black mafics forming a series of plutons dm01b Makkah Suite (dm) Jiddah 210 21'36.45'' N 400 15'44.86'' E Gabbro-Diorite spread across the Jiddah Terrane (northern Asir Terrane). This is a It has a very unreliable date = 817- 0 0 dm01c 21 21'36.45'' N 40 15'44.86'' E Tonalite compositionally diverse package of rocks ranging from gabbros.to 678Ma (presumably U-Pb in zircon). granodiorite. There are evident pegmatic patches, magma mingling and mafic/felsic dyke interactions scattered throughout the plutons. The mineralogy ranges from amphiboles and pyroxenes (minor olivine) in the mafic endmembers to predomiantly plagioclase, horndblende and quartz in the more felsic units.
tfv02 At Ta'if Group (tfv) Jiddah 210 19'20.05'' N 400 21'15.93'' E Chlorite-Schist Fine-very fine grained green/grey micacious schist residing in the Age is unknown, but is indirectly Jiddah terrane just south of the Makkah Suite. This is predominantly dated by the intrusion of the composed of chlorite, muscovite and biotite with minor quartz, alkali- Khasrah Complex at 840-815Ma. feldspar and garnet forming small kinematic clasts. The mineralogy and metamporphic nature suggests greenschist facies metamorphism. Kinematic indicators on both the hand sample and cliff face indicate thrusting to the west.
304 Appendices 1.1 and 1.2 (continued): Midyan and Jiddah terrane samples collected from the Arabian Shield, Saudi Arabia (see Chapter 2.4, Figure 2.10 and Appendix 1.1.1 (Al Bad Suite) and Chapter 2.3.1 (Makkah Suite) for location in the Shield and petrography respectively).
305 1.1.1 Al Bad Granite Super Suite (abg). A mineralogical summary of this suite is presented in Chapter 2.4.
The Al Bad Granite Super Suite is a collective term coined by Johnson (2006) for a large group of granitic units that are exposed by relatively high relief Mountains near the Jordanian border in the northwest part of the Shield. This suite includes the Mabrak and Ghadiyah Granites, Midyan and Haql Suites and the Lawz and Dabbagh Complexes which are distinguished on the 1:250,000 scale geological SGS-TR-2006-4 northern map sheet (Johnson, 2006). In this study, these are grouped based on lithological, geographical and geochronological similarities and have a date of ~577Ma, thus classifying them as post-tectonic (Appendix 1.1).
The granitic subunits often display sharp cross-cutting dyke contacts with fresh road cuttings allowing for ease of sampling (Figure A1.2). A total of 6 samples were collected from the Lawz mountain pluton, which is locally the Lawz Complex (see Appendix 1.1). The pink-grey coarse grained alkali-granite showed no evidence of deformation, but localised country rock xenoliths were evident. These xenoliths are often small (1-3cm) and are predominantly composed of fine grained biotite, quartz and feldspar. Granitic xenoliths may be part of the older Qazaz Granite Super Group (635- 620Ma).
The alkali-feldspar rich Al Bad Suite is homogeneous in mineralogy and texture, composed of perthite (~50-60%), quartz (~40-50%), biotite (<5%) and plagioclase (<5%) that define an alkali-feldspar granite (Figure A1.1). Accessory phases include magnetite, zircon, apatite and fluorite. Textures vary from porphyritic to granular with coarse feldspars surrounded by interlocking quartz-feldspar matrix (Figure A1.2). Subsolidus exsolution textures (perthite) form the majority of the coarse 1-5mm feldspars. These commonly contain inclusions of quartz and albite. Finer <1mm late- stage anhedral quartz crystals fill the void spaces between perthite grains. Remnant subhedral tabular plagioclase and partially oxidised biotite were also observed scattered between feldspar grains.
306 Figure A1.1:A Plutonic classification scheme modified from De la Roche et al. (1980) of the Al Bad Granite Super Suite in the Midyan terrane. These are typical hypersolvous alkali- granites that are isolated from plate boundaries.
One single crystal of microcline also showed signs of microperthitic texture. Plagioclase was infrequently observed and quite difficult to distinguish with dark interference colours, but vague signs of albite polysynthetic twinning indicate a positive identification. Plagioclase interactions with quartz mark rare patches of myrmekite, which encroach the corners of alkali-feldspar crystals. Early formed euhedral-subhedral zircon crystals (<0.5mm in diameter) are relatively abundant as inclusions in quartz and feldspar. Rarely observed interstitial fluorite veinlets (<0.5mm) are confined between quartz/magnetite phases. Apatite is also present at the intersections of quartz crystals. Ferromagnesian amphiboles and pyroxenes appear to be absent in these alkali-granites
307 Figure A1.2: A) Discordant high topographic mountains near Haql (border of Saudi Arabia and Jordan) composed of the Al Bad Granite Super Suite. The highest peak in this photo is Lawz Mountain from which the samples were collected at the base. B) This granitic suite consists of multiple subgroups which are contacted by cross-cutting dykes. C) Exposed fresh outcrop on the ascent to Lawz Mountain from which 6 samples were collected. D) A representation of the coarse-grained pink alkali-granites obtained at Lawz Mountain. Note the relatively simple mineralogy of coarse quartz and alkali-feldspar with scattered black biotite and magnetite. E) A petrographic photograph taken in plane-polarised light of the same sample. Note the hypersolvous nature of the coarse alkali-feldspar grains surrounded by late stage quartz. F) The same petrographic photo taken in cross-polarised light. Note the exsolution texture in the alkali-feldspar grains. The location of all samples collected and a complementary catalogue of this suite is displayed in Figure 2.10 and Appendix 1.1 respectively.
308 Appendix 1.3: Hijaz terrane samples collected from the Arabian Shield, Saudi Arabia (see Chapter 2.4, Figure 2.10 and Chapter 2.3.2 (Shufayyah Complex) and Appendices 1.3.1-1.3.5 (all other suites) for location in the Shield and petrography respectively).
Sample Shield Published Geochronological Age Geological Map Unit Latitude Longitude Rock Type Field Mineralogy + Observations Name Terrane (Johnson, 2006) ay 186 250 09'08.25'' N 380 11'21.47'' E Dacitic-Andesite? Fine-very fine micacious schist with alternating layers of ay 187 Al Ays Group (ay) Hijaz 250 09'07.93'' N 380 11'20.91' E Dacitic-Andesite? volcanic/shale units forming a widespread group in the western side Not directly dated. Structural ay 206 240 24'37.77'' N 380 21'23.92'' E Andesite? of the Shield. Chlorite and biotite assembleges suggest greenschist relationships suggest >700Ma, but facies metamorphism. This is consistent with a sharp contact formed recent SHRIMP suggests 736Ma (rhyolite). by the intrusion of the Radwa Granite, Admar Suite and Mardabah Complex units.
su 214 Shufayyah Complex 230 44'42.57'' N 380 46'49.86'' E Tonalite Medium-coarse grained salt and pepper coloured tonalite forming 0 0 su 215 Hijaz 23 44'42.85'' N 38 46'49.93'' E Tonalite irregular shaped plutons in the western side of the Hijaz terrane. It is U-Pb in Zircon =715Ma su 216 (su) 0 0 Tonalite (undocumented). 23 44'42.76'' N 38 46'50.11'' E primarily composed of plagioclase, biotite and opaques with minor hornblende and intrudes the Al Ays Group.
js 200 Jar-Salajah Complex 240 24'37.83'' N 380 21'23.81'' E Granodiorite Medium-coarse grained pink/grey granite forming subrounded- js 201 240 24'37.70'' N 380 21'23.96'' E Granodiorite U-Pb in zircon=745-695Ma (poorly and Fara' Hijaz elongate plutons at the base the Jabal Radwa Mountain in the js 202 240 24'37.62'' N 380 21'23.72'' E Granodiorite constrained). js 203 Trondhjemite (js) 240 24'37.50'' N 380 21'23.66'' E Granite western side of the Hijaz terrane. It is primarily composed of pink
alkali-feldspar, plagioclase and opaques with minor hornblende . It
forms a sharp contact with the older Al Ays Group.
sf 208 230 45'39.12'' N 380 45'09.59'' E Microgranite Fine-very fine pink/grey volcanics forming irregular shaped plutons sf 209 230 45'39.13'' N 380 45'09.74'' E Rhyolite (intruding the Shufayyah Complex) in the wetern side of the Hijaz Subh Suite (sf) Hijaz Whole rock Rb-Sr isochron=659Ma. sf 211 230 45'39.00'' N 380 45'09.57'' E Rhyolite terrane. The matrix is too fine to distinguish minerals, but judging by sf 213 230 45'38.93'' N 380 45'09.80'' E Diorite the scattered larger grains of quartz and alkali-feldspar, it is assumed to be composed of the same minerals.The grain size varies across the outcrops from fine volcanics-mircogranite interrupted by slivers of micacious schist.
309 Appendix 1.3 (continued): Hijaz terrane samples collected from the Arabian Shield, Saudi Arabia (see Chapter 2.4, Figure 2.10 and Chapter 2.3.2 (Shufayyah Complex) and Appendices 1.3.1-1.3.5 (all other suites) for location in the Shield and petrography respectively).
310 Appendix 1.3 (continued): Hijaz terrane samples collected from the Arabian Shield, Saudi Arabia (see Chapter 2.4, Figure 2.10 and Chapter 2.3.2 (Shufayyah Complex) and Appendices 1.3.1-1.3.5 (all other suites) for location in the Shield and petrography respectively).
Sample Shield Published Geochronological Age Geological Map Unit Latitude Longitude Rock Type Field Mineralogy + Observations Name Terrane (Johnson, 2006) ad 194 240 17'53.09'' N 380 24'43.55'' E Syenite Medium-coarse grained pink/white subcircular syenite plutons ad 195 240 17'52.63'' N 380 24'44.39'' E Syenite confined to the central part of the Hijaz terrane. These are Has 3 unreliable ages using Rb-Sr ad 196 Admar Suite (ad) Hijaz 240 17'52.51'' N 380 24'43.74'' E Syenite composed almost entirely of alkali-feldspar and quartz with minor methods =640, 602, 583Ma. ad 197 240 17'52.79'' N 380 24'43.43'' E Syenite biotite and opaques. There are also numerous very fine grained VG198 240 17'52.83'' N 380 24'44.13'' E Rhyolite granophyric volcanic dykes cross-cutting the plutons, which are assumed to be of similar composition to the granites.
rt 181 250 09'07.28'' N 380 11'21.54'' E Diorite Medium-fine grained dark blue/grey mafic intrusives forming small Age is unknown, but it clearly post rt 182 250 09'07.56'' N 380 11'21.95'' E Diorite isolated plutons in the northwestern part of the Hijaz terrane. dates the deformation of the Al Ays Rithmah Complex (rt) Hijaz rt 183 250 09'07.28'' N 380 11'21.83'' E Diorite These are predominantly composed of plagioclase and greenish Group and intrudes the Admar Suite. rt 185 250 09'07.90'' N 380 11'20.41'' E Gabbro-Diorite pyroxene (clinopyroxene) with minor hornblende, quartz and This suggests it is Ediacaran biotite. There are also some small patches of green needles (<600Ma?). (actinolite-alteration of CPX). These plutons have a distinct intrusion contact with the overlying older Al Ays Group.
mr 188 250 11'28.70'' N 380 29'34.11'' E Syenite Very coarse-coarse grained white/pink syenite forming a series of mr 189 250 11'29.60'' N 380 29'34.28'' E Syenite small isolated plutons (similar to the Rithmah Complex) in the Age is unkown, but structural 0 0 northwestern part of the Hijaz terrane. It constists almost entirely relationships suggest Ediacaran mr 190 Mardabah Complex (mr) Hijaz 25 11'27.94'' N 38 29'33.98'' E Syenite mr 191 250 11'29.42'' N 380 29'35.33'' E Syenite of alkali-feldspar with lesser amounts of biotite and hornblende (<600Ma). CV 192 250 11'28.20'' N 380 29'35.05'' E Granophyre? and minor plagioclase and quartz. There are also numerous cross- CV 193 250 11'27.51'' N 380 29'34.48'' E Granophyre? cutting granophyric volcanic dykes scattered across the plutons.
311 Appendix 1.3 (continued): Hijaz terrane samples collected from the Arabian Shield, Saudi Arabia (see Chapter 2.4, Figure 2.10 and Chapter 2.3.2 (Shufayyah Complex) and Appendices 1.3.1-1.3.5 (all other suites) for location in the Shield and petrography respectively).
312 1.3.1 Jar-Salajah Complex and Fara’ Trondhjemite (js). A mineralogical summary of this suite is presented in Chapter 2.4.
The Jar-Salajah Suite consists of multiple irregular shaped batholithic intrusions spread over both the Midyan and Hijaz terranes in the northwestern part of the Shield. These units include the Jar and Salajah batholiths and Fara trondhjemite, which are lithologically similar and contain no obvious boundary separation, so are treated as one unit (Johnson, 2006). The suite is emplaced into already deformed volcanics of the Al Ays (~745-700Ma) and Zaam (760-710Ma) Groups. The Jar-Salajah Suite has been poorly constrained at 745-695Ma and according to Johnson (2006), intrudes the Jabal Wask ophiolite. This suggests that it post dates the amalgamation and suturing of the Midyan and Hijaz terranes.
The well exposed nature of the outcrops are often met by sharp contacts with the older Al Ays Group volcanics and provided ideal conditions for sampling (Figure A1.3). A total of 7 units were collected here including 3 volcanic samples from the Al Ays Group (see Appendix 1.3). No obvious deformation or mingling was exhibited. Localised pink feldspar and hydrous biotite veining were pronounced and scattered throughout the outcrops. This could possibly be due to the vicinity of the Hudayrah- Jabal Ess Fault Zone and/or intrusion of the near by mountainous Jabal Radwa Batholith (Figure A1.3).
Variations in biotite and alkali-feldspar separate the homogeneous Jar Salajah granodiorite. However, it is predominantly composed of plagioclase (~35-40%), quartz (~30-35%), alkali-feldspar (<15%) and biotite (~15%) that define a granodiorite/granite composition (Figure A1.5). Minor phases include hornblende and magnetite. Textures are homogeneously porphyritic defined by 5-10mm euhedral-subhedral partial weathered plagioclase and alkali-feldspar grains (Figure A1.3). These coarse feldspars are almost exclusively surrounded by finer (<2mm) anhedral quartz and occasional orthoclase grains. Coarse (1-5mm) randomly scattered subhedral quartz grains are also sandwiched between finer interstitial quartz phases (Figure A1.3). There are rarely seen microcline grains containing microperthitic texture, which also occurs on some coarse sanidine grains. Small patches of subhedral hornblende bearing magnetite inclusions are often observed with surrounding interstitial biotite.
313 1.3.2 Subh Suite (sf). A mineralogical summary of this suite is presented in Chapter 2.4.
The Subh Suite consists of small subrectagular-rectangular shaped plutons confined by the southern Hijaz terrane, approximately mid way between the Yanbu and B’ir Umq Sutures. This suite consists of two complexes, but in this study, these are lithologically grouped. The units are emplaced into the already deformed Birak Group (~805Ma) and Milhah Formation (~715Ma) and cross-cuts the Shufayyah Complex (~715Ma). The crystallisation age of this suite is unknown, but has an unreliable Rb-Sr whole rock age of 659Ma (Johnson, 2006).
Rolling hills composed of the Subh Suite are often met by internal compositional contacts between outcrops (Figure A1.3). A total of 4 units were collected here including one diorite and 2 rhyolitic volcanics (see Appendix 1.3). This suite appears to be a mixture of plutonic and volcanic rocks that texturally point to shallow emplacement in the crust. Randomly scattered green/grey dioritic dykes cross- cut the pink alkali-feldspar granite landscape. Most granite is microgranite and hard to distinguish between neighbouring rhyolitic units. A subtle reduction in grainsize is all that separates the microgranites from cross-cutting rhyolitic dykes. This relationship suggests emplacement of fine grained granite at shallow levels, followed by surface eruption. There was no evidence of deformation exhibited at any outcrops.
Variations in grainsize are all that separate the homogeneous microgranite and rhyolite. Initial sampling resembled microgranite, but a closer inspection reveals it is most likely a rhyolite specimen (Figure A1.3). Alkali-feldspar (~50%), quartz (~25%) and plagioclase (~25%) compose the coarse (1-5mm) phenocrysts, whilst the matrix consists of a fine (<1mm) quartz and orthoclase groundmass (Figure A1.3). The mineralogy, in addition to the porphyritic texture, defines a rhyolitic composition (Figure A1.5). The feldspar phenocrysts are euhedral-subhedral in nature and the quartz phenocrysts often display embayed shapes against the groundmass. This appears to be consistent with late-stage dissolution with the melt.
314 Figure A1.3: A) Jar-Salajah Complex granodiorite forming a sharp contact with the older Al Ays Group (ay) volcanics at the base of the Jabal Radwa (post- tectonic granite) Batholith. A total of 5 samples were collected at this contact. B) A representation of the coarse-grained Jar-Salajah Complex granodiorites. Note the abundance of amphiboles and large alkali-feldspar crystals. C) A petrographic photograph taken in plane-polarised light of the same granite sample. D) The same petrographic photo taken in cross-polarised light. Note the interstitial quartz and alkali-feldspar and coarse grain junctions. E) Rolling low hills composed of the Subh Suite volcanics just east of Yanbu al Bahr. A total of 4 samples were collected here including a diorite intrusive. F) A representation of the rhyolites collected from the Subh Suite. Note the large alkali-feldspar and plagioclase phenocrysts around the glassy groundmass G) A petrographic photograph of the same rhyolite sample taken in plane-polarised light. Note the very large zoned plagioclase phenocrysts and the fine quartz groundmass. H) The same petrographic photo taken in cross-polarised light. The location of all samples collected and a complementary catalogue of this suite is displayed in Figure 2.10 and Appendix 1.3 respectively.
315 1.3.3 Admar Suite (ad). A mineralogical summary of this suite is presented in Chapter 2.4.
The Admar Suite is a collection of large irregular to subrounded granitic plutons, located ~50-100km east of Yanbu’ al Bahr in the central part of the Hijaz terrane. These undeformed plutons lie south east of the Yanbu Suture and intrude the older deformed volcanics of the Al Ays Group (745-700Ma). The age of this group is classified as unknown and according to Johnson (2006) has 3 unreliable Rb-Sr ages of 640, 602 and 583Ma.
The rounded weathered nature of theses outcrops created difficult sampling conditions. However, cross-cutting rhyolitic dykes provide sufficient exposed areas where a total of 5 samples were collected (Figure A1.4 and Appendix 1.3). No evidence of mingling was observed, but localised 1-3cm patches of coarse biotite and hornblende mineral assemblages were evident. Rounded granitic outcrops are sharply cross-cut by rhyolitic dykes <1m in length. These are porphyritic in nature and consist of coarse (1-3mm) alkali-feldspar and quartz phenocrysts surrounded by a glassy quartz matrix
The white/pink sample appears to be medium-coarse grained and composed of alkali-feldspar (65-70%), biotite + hornblende (~15-20%) and plagioclase (~5%) that define a syenitic composition (Figure A1.5). Minor and accessory phases include quartz, microcline, titanite, magnetite, zircon and apatite. Textures are homogeneously equigranular, dominated by large (5-10mm) subhedral perthitic feldspars, but occasional granophyric patches of finer (<1mm) quartz and alkali-feldspar are observed. There is a relatively high proportion of subhedral biotite and hornblende that defines a somewhat finer matrix situated between large perthitic feldspars. Biotite along with quartz appears to be an interstitial phase. Well developed interstitial titanite crystals are also emplaced in the finer grained sections between feldspars. One crystal of microcline was also observed and displayed microperthitic texture. Magnetite was confined as inclusions in hornblende. Euhedral-subhedral <0.2mm zircon crystals were mostly confined to feldspars, but occasionally observed along with apatite as inclusions in biotite grains.
316 1.3.4 Mardabah Complex (mr). A mineralogical summary of this suite is presented in Chapter 2.4.
The Mardabah Complex forms a small group of circular shaped plutons confined to the central Hijaz terrane ~50km east of the Yanbu Suture north of Yanbu al Bahr. These isolated, undeformed, felsic intrusions are not directly dated, but are emplaced in the folded Ediacaran Hadiyah Group (Johnson, 2006). This structural relationship defines one of the youngest Neoproterozoic units in this western part of the Shield.
The well exposed rounded outcrops were difficult to sample, but exhibited cross-cutting dyke contact relationships that provided opportunity to obtain fresh samples (Figure A1.4). A total of 6 samples were collected here including two granophyric dyke samples (see Appendix 1.3). No evidence of mingling or deformation was observed, but some sections displayed a reduction in grainsize and concentration of hydrous ferromagnesian minerals. Granophyric dykes separate the vast areas of granitic plutons with sharp abrupt contacts. These shallow extrusives form a glassy texture (<0.1mm) presumably composed of quartz-feldspar intergrowths.
The white/pink very coarse grained sample is almost pegmatitic in nature and is composed of alkali-feldspar (~75-80%), biotite (~10%) and hornblende (~10%) that define a syenitic composition (Figure A1.5). Minor and accessory phases include quartz, plagioclase, olivine, magnetite, zircon and apatite. Textures are homogeneously equigranular and are defined by very coarse (10-15mm) subhedral-anhedral perthitic feldspars (Figure A1.4). Occasional patches of porphyritic texture composed of quartz, sanidine and biotite are also observed. Perthitic feldspar dominates the mineralogy, but remnant plagioclase laminar twinning is observed in highly weathered grains.
Small <2mm subhedral olivine grains (possibly fayalite) are exclusively confined as inclusions in biotite (Figure A1.4). Early stage hornblende and biotite are synonymous with magnetite inclusions. Biotite occurs in two stages characterised by the presence or absence of magnetite. The latter forms interstitial grains alongside anhedral quartz at perthitic feldspar junctions. Euhedral apatite and clearly visible (~0.5mm) prismatic zircon crystals are observed in both biotite and perthite grains.
317 Figure A1.4: A) Rounded low hills of the Admar Suite east of Yanbu al Bahr. A total of 5 samples were collected here. B) A representation of the syenites collected from the Admar Suite. C) A petrographic photograph of the same sample taken in plane-polarised light. Note the abundant hornblende and biotite. D) The same petrographic photo taken in cross-polarised light. Note the coarse perthitic feldspars. E) Isolated hills composed of the Mardabah Complex syenite east of Yanbu al Bahr. F) A representation of the syenites collected from the Mardabah Complex. G) A petrographic photograph of the same syenite sample taken in plane-polarised light. Note the olivine inclusions in biotite. H) The same petrographic photo taken in cross-polarised light. Note the coarse perthitic feldspars. The location of all samples collected and a complementary catalogue of this suite is displayed in Figure 2.10 and Appendix 1.3 respectively.
318 1.3.5 Rithmah Complex (rt). A mineralogical summary of this suite is presented in Chapter 2.4.
The Rithmah Complex is a singular unit comprised of 4 small discordant rounded plutons situated east of the Yanbu Suture in the Hijaz terrane. This mafic complex is predominantly composed of diorites and gabbros and is not directly dated. However, this unit clearly intrudes both the older Al Ays Group (730-700Ma), but more importantly, the Admar Suite (640-583Ma). This structural relationship categorises this as an Ediacaran post-tectonic unit (Johnson, 2006).
This mafic pluton appeared to exhibit cumulate layering defined by pyroxene gabbros that gradationally transform into amphibole-pyroxene diorites. These diorites display sharp contacts with the older Al Ays Group volcanics (Figure A1.5). This boundary provided ample opportunity to sample the two units, from which a total of 4 mafic and 2 volcanics were collected (see Appendix 1.3). Despite the internal cumulate layering, no evidence of magma mingling was recorded. Some dioritic sections displayed concentrations of pyroxene crystals, which appeared to be rimmed with green needle like grains (actinolite).
This mafic mineralogy is predominantly composed of plagioclase (~60%), clinopyroxene (~30%) and hornblende (~10%) and defines a dioritic composition (Figure A1.5). Minor and accessory phases include quartz, magnetite and actinolite. Texturally, this would be classified as a porphyritic style diorite. This contains 5-10mm subhedral clinopyroxene and occasional hornblende crystals, surrounded by a matrix composed of finer (<3mm) euhedral triple junction adcumulate plagioclase. The majority of cumulate crystals are clinopyroxene, with few containing actinolite and magnetite reaction rims (Figure A1.5). There are a few cumulate crystals of hornblende scattered throughout the slide. Post cumulate interstitial anhedral quartz is confined to the plagioclase matrix. Magnetite appears as both early and late stages: confined as inclusions in hornblende and clinopyroxene; and amongst adcumulate plagioclase crystals and actinolite alteration rims.
319 Figure A1.5: A) Contact between the Rithmah Complex and the overlying Al Ays Group east of Yanbu al Bahr. A total of 6 samples were collected here. B) A representation of the coarse grained dioritic suite. Note the coarse pyroxenes. C) A petrographic photograph of the same sample taken in plane polarise light. Note the alteration rims around cumulate pyroxene grains. D) The same petrographic photo taken in cross-polarised light. E)A Plutonic classification scheme modified from De la Roche et al. (1980) of the Hijaz terrane samples. Volcanics samples are defined as black squares, whilst the red circles are granitic suites. The two syenitic suites (far left) correlate with the perthitic Admar and Mardabah syenites. Classic I-type mineralogy correlates with the remainder of the red circles (right). The location of all samples collected and a complementary catalogue of this suite is displayed in Figure 2.10 and Appendix 1.3 respectively.
320 Appendix 1.4: Ha’il terrane samples collected from the Arabian Shield, Saudi Arabia (see Chapter 2.4, Figure 2.10 and Appendix 1.4.1 (Idah Suite) and Chapter 2.3.4 (Abanat Suite) for location in the Shield and petrography respectively).
Sample Shield Published Geochronological Age Geological Map Unit Latitude Longitude Rock Type Field Mineralogy + Observations Name Terrane (Johnson, 2006) id 155 270 03'44.47'' N 410 17'59.11'' E Alkali-Granite Very coarse-coarse grained pink/white granites forming rounded id 156 270 03'44.38'' N 410 17'59.55'' E Alkali-Granite plutons that reside in the Ha'il terrane and extend into the northern This has been directly dated id 159 Idah Suite (id) Ha'il 270 03'44.28'' N 410 17'58.70'' E Alkali-Granite part of the Afif terrane. This is almost entirely composed of pink alkali- (presumably U-Pb in zircon) at 620- id 163 270 01'15.74'' N 410 19'17.49'' E Alkali-Granite feldspar with minor quartz, hornblende and green amphiboles 615Ma. id 164 270 01'15.60'' N 410 19'17.96'' E Alkali-Granite (arfvedsonite).Accessory phases include small (<1mm) veins of sulphides (mostly pyrite). This unit intrudes the Hadn Formation.
hn160 270 03'43.74'' N 410 17'58.38'' E Rhyodacite? Fine-medium grained grey/white felsic volcanics forming Hadn Formation (hn) Hail hn162 270 03'43.55'' N 410 17'58.48'' E Rhyolite unmetmorphosed volcanic sheets deposited in the Ha'il terrane. The scattered larger grains of quartz (minor alkali-feldspar) are surrounded SHRIMP on zircon = 598Ma. by a glassy quartz matrix and scattered opaques. This unit is intruded by younger Idah Suite granites and overlies older units such as the Banana Formation, suggesting it could be part of a post-amalgamation basin.
aa166 270 18'44.01' N 410 24'34.43'' E Akali-Granite Medium-coarse grained grey/yellow undeformed granite exposed by aa167 270 18'43.63' N 410 24'33.52'' E Akali-Granite topographic highs in the Ha'il terrane, but also extending into the This has been directly dated Abanat Suite (aa) Hijaz aa168 270 18'44.08' N 410 24'33.87'' E Akali-Granite northern parts of the Afif and Ad Dawadimi terranes. This is primarily (presumably by U-Pb in zircon) at 154(d) 270 18'23.63'' N 410 21'01.99'' E Rhyolite composed of alkali-feldspar and some quartz, but also contains large 585-570Ma. green amphiboles (arfvedsonite). There are also minor amounts of purple flourine and black tourmaline. Plutons contain cross-cutting felsic granophyric volcanic dykes scattered throughout the outcrops. It is lithologically very similar to the Ar Ruwaydah Suite in the Ad Dawadimi Terrane.
321 Appendix 1.4 (continued): Ha’il Terrane samples collected from the Arabian Shield, Saudi Arabia (see Chapter 2.4, Figure 2.10 and Appendix 1.4.1 (Idah Suite) and Chapter 2.3.4 (Abanat Suite) for location in the Shield and petrography respectively).
322 1.4.1 Idah Suite (id). A mineralogical summary of this suite is presented in Chapter 2.4.
The granitic plutons of the Idah Suite form a series of elliptical shaped, low rise hills spread over the northeastern part of the Shield. Unlike the Abanat Suite, this group of plutons is not renamed with emplacement into various terranes. These undeformed granitic rocks are associated with gold-bearing deposits and have been directly dated at 620-615Ma (Johnson, 2006). These plutons often met with sharp intrusional contacts with the older Hadn Formation (Figure A1.6). A total of 7 samples, including 2 dacitic volcanics, were sampled (Appendix 1.4). The rhyodacitic Hadn Formation units are composed primarily of plagioclase (~40%), quartz (~30%) and alkali-feldspar (~30%) phenocrysts, but are not discussed here. The pink-white Idah Suite plutons showed no evidence of deformation or mingling, but localised 1-2m slip fault zones characterised by biotite and 1-3cm magnetite-biotite patches were observed.
Varying amounts of biotite are all that separate the mineralogically homogeneous Idah Suite. Perthite (~55-60%), quartz (~30%) and plagioclase (~5-10%) are the main constituents that define an alkali-granite composition (Figure A1.6). Minor phases include biotite, hornblende, hastingsite and magnetite. Textures are equigranular characterised by coarse (5-10mm) perthitic feldspars and quartz (Figure A1.6). However, minor patches of interstitial biotite and quartz between large perthitic feldspars, often create a porphyritic style texture. Subsolidus perthite dominates the feldspar mineralogy, but there are occurrences of early stage euhedral-subhedral plagioclase grains (Figure A1.6).
Biotite possibly occurs as both an early stage and later interstitial mineral phase. The bladed euhedral biotite, alongside subhedral hornblende, contain magnetite inclusions. This is not observed in the anhedral interstitial biotite that appears to overprint the corners of mineral intersections. Similarly, quartz occurs as coarse (1- 5mm) subhedral grains, but also finer (<1mm) interstitial anhedral grains at the intersections of perthitic feldspars. Yellow halos in early biotite and perthite grains mark the rare occurrence of <0.2mm subhedral zircon crystals. Occasional patches of interstitial green hastingsite overprint the intersections of perthitic feldspars.
323 Figure A1.6: A) Unconformable contacts between the older Hadn Formation volcanics and the intruding Idah Suite alkali-granite. A total of 7 samples were collected here, including 2 older volcanic samples. B) A representation of the coarse-grained alkali-granites obtained at the contact. Note the abundance of alkali-feldspar crystals. C) A petrographic photograph taken in plane-polarised light of the same sample. D) The same petrographic photo taken in cross- polarised light. Note the high proportion of perthitic feldspars. E)A Plutonic classification scheme modified from De la Roche et al. (1980) of the Ha’il terrane samples. Both the Abanat (red circles) and Idah (orange circles) Suites are typical hypersolvous alkali-granites, separated by the presence of Na- bearing pyroxenes/amphiboles. The Hadn Formation units (black squares) are potential crustal sources for the intruding economic Abanat Suite (Chapter 7.7). The location of all samples collected and a complementary catalogue of this suite is displayed in Figure 2.10 and Appendix 1.4 respectively.
324 Appendix 1.5: Ad Dawadimi terrane samples collected from the Arabian Shield, Saudi Arabia (see Chapter 2.4, Figure 2.10 and Chapter 2.3.5 (Malik Granite) and Appendices 1.5.1-1.5.3 (all other suites) for location in the Shield and petrography respectively).
Sample Shield Published Geochronological Age Geological Map Unit Latitude Longitude Rock Type Field Mineralogy + Observations Name Terrane (Johnson, 2006) nr 117 230 43'45.04'' N 440 41'20.87'' E Granite Medium-coarse grained salt and pepper coloured granite comprised as nr 119 Ad 230 43'45.19'' N 440 41'21.35'' E Granite The main body has been dated Najirah Granite (nr) a widespread batholith in the Ad Dawadimi terrane. The mineralogy is nr 120 Dawadimi 230 43'43.93'' N 440 41'21.06'' E Granite at 641Ma using U-Pb in zircons, composed entirely of alkali-feldspar, quartz and minor biotite. There are nr 136 240 22'46.88'' N 440 21'38.39'' E Alkali-Granite but also at 576Ma using the also patches containing minor amounts of plagioclase and opaques. This SHRIMP. suite intrudes the older Abt Formation.
mu 131 230 51'27.26'' N 430 06'52.78'' E Rhyodacite Fine grey/green mafic and felsic volcanics forming thick sequences 0 0 mu 132 Murdama Group Ad 23 51'14.85'' N 43 07'02.82'' E Rhyodacite covering a vast area of the Ad Dawadimi terrane. This package contains The age of this suite is poorly mv 134 (mu) Dawadimi 240 22'49.06'' N 440 21'36.44'' E Basaltic-Andesite? constrained, but is dated at primarily quartz/alkali-feldspar assemblages and some samples contain mv 135 240 22'49.13'' N 440 21'37.86'' E Basaltic-Andesite? 630Ma (using zircons from chlorite alteration suggesting low grade greenschist facies volcanics).
metamorphism. This unit is intruded by the Abanat, Idah and Al
Khushaymiah Suites.
kg 142 250 07'55.34'' N 430 47'12.66'' E Leucogranite Medium grained white/grey granite forming a subrectanuglar pluton The age is unknown, but is 0 0 kg 145 Ad 25 07'54.98'' N 43 47'13.18'' E Leucogranite confined to the northeastern part of the Ad Dawadimi terrane. The red thought to be 620-615Ma, which kg146 Malik Granite (kg) Dawadimi 250 07'54.67'' N 430 47'12.44'' E Leucogranite is the same age as the Idah Suite kg 148 250 07'56.38'' N 430 47'11.20'' E Granite garnet-bearing leucocratic mineralogy (quartz and minor alkali-feldspar 0 0 (mapping relationship). kg 150 25 07'56.42'' N 43 47'10.82'' E Granite and bitotite/muscovite) is consistent with a crustally-dervied granite.
This suite intrudes the older Abt Formation and Idah Suite.
ku 121 230 42'57.09'' N 440 34'37.86'' E Granite Medium-fine grained white/pink granite exposed by isolated hills in the Ar Ruwaydah is divided into two ku 122 Ar Ruwaydah Suite Ad 230 42'58.29'' N 440 34'40.95'' E Granite Ad Dawadimi terrane. This undeformed suite varies in composition subunits: Khurs Granite has been 0 0 dated at 605-598Ma and 579- ku 123 (ku) Dawadimi 23 42'58.68'' N 44 34'44.32'' E Granite from quartz-plagioclase-biotite granites through to pink alkali-feldspar- ku 139 240 22'43.75'' N 440 21'40.56'' E Alkali-Granite 565Ma (U-Pb in zircons and quartz microgranite. This suite intrudes the Abt Formation and cross- SHRIMP respectively) and the cuts the Najirah Granite and is subdivided into two units: Khurs Granite Arwa Granite has been dated at (white); and Arwa Granite (pink). 587Ma and 575Ma (Rb-Sr and SHRIMP respectively). ky 124 230 49'48.87'' N 430 15'16.56'' E Rhyodacite Medium-coarse grained grey/white granite and felsic volcanics, forming 0 0 ky 125 Al Khushaymiyah Ad 23 49'31.37'' N 43 15'33.00'' E Rhyodacite a suite of circular undeformed intrusions in the Ad Dawadimi terrane. This suite has been directly ky 126 Suite (ky) Dawadimi 230 49'43.33'' N 430 15'36.21'' E Rhyodacite dated at 611-595Ma (U-Pb in This suite is composed of equal amounts of quartz, alkali-feldspar, ky 129 230 49'39.69'' N 430 11'42.07'' E Quartz-Monzonite zircon). ky 130 230 49'33.49'' N 430 11'10.33'' E Quartz-Monzonite plagioclase and biotite. and intrudes the Murdama Group
325 Appendix 1.5 (continued): Ad Dawadimi Terrane samples collected from the Arabian Shield, Saudi Arabia (see Chapter 2.4, Figure 2.10 and Chapter 2.3.5 (Malik Granite) and Appendices 1.5.1-1.5.3 (all other suites) for location in the Shield and petrography respectively).
326 Appendix 1.5 (continued): Ad Dawadimi Terrane samples collected from the Arabian Shield, Saudi Arabia (see Chapter 2.4, Figure 2.10 and Chapter 2.3.5 (Malik Granite) and Appendices 1.5.1-1.5.3 (all other suites) for location in the Shield and petrography respectively).
327 1.5.1 Najirah Granite (nr). A mineralogical summary of this suite is presented in Chapter 2.4.
The Najirah Granite consists of multiple large batholiths straddling the border between the Afif and Ad Dawadimi terranes in the eastern part of the Shield. This undeformed unit is directly dated at 640Ma, but anomalous localised plutons have been dated at 575Ma (Johnson, 2006). This unit intrudes the Abt Formation, but is itself intruded by the both the Idah and Ar Ruwaydah Suites. These rounded granitic hills are well exposed, but provide difficulties in obtaining fresh samples (Figure A1.7). However, a total of 4 granitic samples were collected (see Appendix 1.5).
No direct evidence of mingling or deformation was observed, but gradational mineralogical changes form coarse (5-25mm) white plagioclase to fine (<5mm) pink alkali-feldspar granite was apparent. This pattern was also observed for hornblende and biotite. Quartz was relatively absent until its gradual appearance in the alkali-feldspar endmembers.
Despite fluctuations in biotite concentration, the Najirah Granite is homogeneous in both texture and mineralogy and composed of plagioclase (~40%), alkali-feldspar (~35%), quartz (~20%) and biotite (~5%) that define a granite/alkali- granite composition (Figure A1.8). Accessory phases include microcline and magnetite. These granites range from porphyritic to granular texture with scattered coarse (5-25mm) euhedral-subhedral plagioclase grains constituting the porphyritic appearance. Finer (<5mm) interlocking grains of weathered alkali-feldspar, quartz and biotite provide the mineralogical network between coarse plagioclase grains. Alkali- feldspar, together with quartz, appears to be primarily in the finer mineral phases. There also appears to be some late stage anhedral interstitial quartz at the intersections of plagioclase grains. The alkali-feldspar and rare microcline are highly weathered, but possibly exhibit microperthitic texture. Biotite exclusively hosts magnetite inclusions and is thought to be a relatively early crystallisation phase.
328 Figure A1.7: A) Rolling low hills composed of the Najirah Granite east of the Halaban Suture. A total of 4 samples were collected here. B) A representation of the granites collected from the Najirah Granite. Note the large plagioclase grains creating a porphyritic texture. C) A petrographic photograph of the same granite sample taken in plane-polarised light. D) The same petrographic photo taken in cross-polarised light. Note the abundant microperthitic texture feldspars. The location of all samples collected and a complementary catalogue of this suite is displayed in Figure 2.10 and Appendix 1.5 respectively.
329 1.5.2 Ar Ruwaydah Suite (ku). A mineralogical summary of this suite is presented in Chapter 2.4.
The Ar Ruwaydah Suite forms a small cluster of irregular shaped plutons that are straddling the Halaban Suture in the eastern part of the Shield. These are separated into the Khurs and Arwa Granites and are distinct from the neighbouring Abanat Suite by the absence of REE mineral occurrences (Johnson, 2006). Granites are undeformed and split into two age groups according to Johnson (2006): white leucocratic Khurs Granite, which yields two zircon ages ranging from 605-598Ma and 579-565Ma (SHRIMP); and pink Arwa Granite, which is associated with an unreliable Rb-Sr isochron of 587Ma and a SHRIMP age of 575Ma.
Although well exposed, the rounded outcrops provide difficulties in obtaining fresh samples (Figure A1.9). However, a total of 4 granitic samples were collected including 3 white leucocratic granites and one pink microgranite, presumably from the Khurs and Arwa units respectively (see Appendix 1. 5). There is no evidence of magma mingling, but rather a localised gradational reduction in biotite and plagioclase. Some sections contain grainsize reduction coinciding with centimetre scale quartz veining. This produced a unit that ranged from porphyritic plagioclase-quartz-biotite granites to fine grained equigranular quartz-feldspar biotite absent granites.
Fluctuations in biotite and plagioclase concentration are all that separate the mineralogically homogeneous nature of the Ar Ruwaydah granite. Alkali-feldspar (~40%), quartz (~30%), plagioclase (~25%) are the dominant minerals that define a granite/alkali-granite (Figure A1.8). Accessory phases include magnetite and hastingsite. Textures are predominantly porphyritic, dominated by 5-10mm subhedral microcline and rare quartz and orthoclase (Figure A1.9). These are interrupted by patches of <1mm biotite, quartz and alkali feldspar sandwiched between larger feldspar grains. The majority of the coarse feldspar is microcline that exhibits microperthitic texture (Figure A1.9). However, there are also randomly scattered coarse plagioclase grains that display remnant polysynthetic twinning.
330 There appears to be two quartz crystallisation phases: initial coarse (5-10mm) subhedral quartz, plagioclase and alkali-feldspar; and fine (<2mm) late stage anhedral interstitial quartz and biotite. Scattered interstitial hastingsite is also observed at feldspar grain intersections and as inclusions in coarse microcline. With the exception of inclusions in biotite, accessory magnetite appears to be a late crystallisation phase, commonly appearing at the junctions of feldspar grains.
Figure A1.8: A Plutonic classification scheme modified from De la Roche et al. (1980) of the Ad Dawadimi terrane. The Najirah Granite (red circles) are intruded by the Ar Ruwaydah Suite (green circles) and are both classified as typical hypersolvous granites/alkali-granite that are juxtaposed to the Halaban Suture zone, but contain geochemically distinct mantle sources (Chapter 7). The Al Khushaymiyah Suite and Murdama Group volcanics are represented with blue circles/squares and black squares respectively.
331 1.5.3 Al Khushaymiyah Suite (ky). A mineralogical summary of this suite is presented in Chapter 2.4.
The Al Khushaymiyah Suite is a collective term for a group of massive circular plutons spread over the southern Ad Dawadimi terrane. This constitutes individually named plutons including the Al Khushaymiyah batholith, Uyaijah ring structure, Fahwah batholith, Umm Makh batholith and Al Hawshah batholith with coeval contact relationships combining them into one unit (Johnson, 2006). These intrude the older Murdama Group sediments (~630Ma) and are directly dated at 611-595Ma. The Murdama sediments are a series of rhyodacite and latite samples (Appendix 1.5) composed primarily of plagioclase (~35%), quartz (~30%), alkali-feldspar (~30%) and biotite (~5%) and plagioclase (~75%), clinopyroxene (~10%), hornblende (~10%) and quartz (~5%) respectively, but are not discussed further in this section.
Granitic units are undeformed and poorly exposed, despite their prominent nature on the geological map. However, drainage depressions provided opportunity to collect fresh samples (Figure A1.9). A total of 5 samples were collected including 3 rhyolitic volcanics (see Appendix 1.5). The volcanic units are composed of quartz (~45%), plagioclase (~30%), alkali-feldspar (~20%) and biotite (~5%) and easily distinguished from the white/grey amphibole-bearing granites. There is no evidence of magma mingling, but rather abrupt contacts marked by glassy volcanics. Localised quartz veinlets are prominent, likely related to the proximity Arja-Jibal Zaydi Fault.
Al Khushaymiyah plutonic samples are homogeneous in mineralogy and texture and are composed of plagioclase (~40%), alkali-feldspar (~40%) and quartz (~10-20%) that define a quartz monzonite (Figure A1.8). Minor phases include biotite, magnetite, microcline, titanite and hastingsite. Textures are equigranular, dominated by 2-3mm interlocking quartz, plagioclase and microperthitic feldspars (Figure A1.9). Occasional isolated porphyritic patches of <1mm biotite, quartz and alkali feldspars are also observed. Microcline is rare and exhibits microperthitic texture (Figure A1.9). Subhedral hornblende exclusively hosts all the magnetite observed. Quartz occurs as two crystallisation phases: initial subhedral quartz, plagioclase and alkali-feldspar; and late stage anhedral interstitial quartz and biotite. Scattered interstitial titanite and hastingsite are also observed at grain intersections.
332 Figure A1.9: A) Rounded boulders composed of the Ar Ruwaydah granite east of the Halaban Suture. A total of 4 samples were collected here. B) A representation of the granites collected from the Ar Ruwaydah Suite. Note the large feldspar crystals define a porphyritic texture. C) A petrographic photograph of the same rhyolite sample taken in plane-polarised light. Note the accessory hastingsite. D) The same petrographic photo taken in cross-polarised light. Note the perthitic texture of the feldspars. E) Poorly exposed Al Khushaymiyah quartz-monzonite confined to drainage depressions. A total of 5 samples were collected here including 3 rhyolitic samples. F) A representation of the coarse-grained quartz monzonite obtained at the contact. G) A petrographic photograph taken in plane-polarised light of the same sample. H) The same petrographic photo taken in cross-polarised light. Note the perthitic textured feldspar. The location of all samples collected and a complementary catalogue of this suite is displayed in Figure 2.10 and Appendix 1.5 respectively.
333 Appendix 1.6: Tathlith Terrane samples collected from the Arabian Shield, Saudi Arabia (see Chapter 2.4, Figure 2.10 and Appendix 1.6.1 for location in the Shield and petrography respectively).
Sample Shield Published Geochronological Age Geological Map Unit Latitude Longitude Rock Type Field Mineralogy + Observations Name Terrane (Johnson, 2006) ao 83 200 23'40.36'' N 440 18'04.29'' E Alkali-Granite Medium-fine grained pink/grey/salt & pepper coloured units ao 85 200 23'40.32'' N 440 18'05.19'' E Alkali-Granite Age is unknown, but structural comprising small isolated subrounded plutons in the Tathlith ao 87 200 24'53.63'' N 440 14'50.11'' E Gabbro-Norite relationships with the Bani ao 88 200 24'53.65'' N 440 14'50.49'' E Gabbro-Norite Ghayy Group place it as Al Hafoor Suite (ao) Tathlith terrane. The mineralogy ranges from alkali-feldspar-quartz ao 98 200 24'39.90'' N 440 14'04.79'' E Rhyodacite Ediacaran. ao 101 200 24'40.78'' N 440 14'06.56'' E Rhyodacite granites, plagioclase-quartz rich volcanics to plagioclase-hornlende- MD93 200 24'40.92'' N 440 14'07.05'' E Granodiorite amphibole mafics. There are also numerous cross-cutting MD95 200 24'40.78' N 440 14'05.02'' E Granodiorite intermediate dykes scattered throughout the plutons.
334 1.6.1 Al Hafoor Suite (ao). A mineralogical summary of this suite is presented in Chapter 2.4.
The Al Hafoor Suite forms a cluster of subrounded gabbroic-granitic plutons, confined to the eastern margin of the Shield, near the city of Sabha in the Tathlith terrane. This unit comprises the Yild Complex and Jasl Pluton (Johnson, 2006), which lie east of the Nabitah Orogenic Belt and south of the Ruwah Fault Zone. These undeformed mafic and felsic units have an unknown age, but post-date the Bani Ghayy Group volcanic sediments. This is determined from structural relationships on the 1:250, 000 scale geological SGS-TR-2006-4 southern map sheet (Johnson, 2006).
This suite is marked by poorly exposed and rounded outcrops, cross-cutting dykes and compositional boundaries (Figure A1.11). A total of 8 samples were collected here including alkali-granites, granodiorites, dacitic volcanics and mafic gabbros (see Appendix 1.6). No evidence of mingling was observed in the plutons, but 5-10cm mafic pyroxene-bearing enclaves were present in the gabbroic units. Dioritic dykes separate the vast fields of salt and pepper coloured dacitic volcanics, which in turn are separated from the alkali-granitic and gabbroic plutons (Figure A1.11). All units displayed primary magmatic texture, exhibiting no signs of deformation.
Volcanic units are composed of coarse (2-5mm) plagioclase (~40%), quartz (~30%) and alkali-feldspar (~30%) phenocrysts with minor (<5%) interstitial late stage biotite. Minor opaques and rare plagioclase grains are confined as inclusions in biotite. The plagioclase phenocrysts exhibit composition zoning and are surrounded by a fine matrix composed of recrystallised quartz grains. Hornblende also appears as late stage crystals rimming the edges of plagioclase phenocrysts. The dioritic units (Figure A1.10) are primarily composed of plagioclase (~65%), quartz (~<20%), hornblende (~<15%) and clinopyroxene (<10%). The gabbroic samples consist of plagioclase (~45%), clinopyroxene (~35%), hornblende, olivine and spinel (<5%). Both the gabbroic and diorite units are not discussed further.
The pink Al Hafoor sample is medium-fine grained and composed of alkali- feldspar (~40%), quartz (~40%), plagioclase (~10%), biotite and hornblende (<10%) that define an alkali-granite composition (Figure A1.10). Accessory phases include
335 magnetite and hastingsite. Textures are homogeneously equigranular, but quartz-alkali- feldspar intergrowths define small patches of granophyric texture. Interlocking quartz and predominately orthoclase grains are rarely interrupted with post-cumulate hornblende (Figure A1.11). Hastingsite is rare, but occurs as late stage interstitial grains together with biotite. Magnetite appears as inclusions in hornblende and at junctions of interstitial hastingsite.
Figure A1.10:A Plutonic classification scheme modified from De la Roche et al. (1980) of the Al Hafoor Suite in the Tathlith terrane. This suite is a diverse package of rocks ranging from gabbros to alkali-granites (red circles) and extrusive volcanics (red squares).
336 Figure A1.11: A) Poorly exposed discordant low hills composed of Al Hafoor alkali-granite near Sabha, south of the Ruwah Fault Zone. B) This suite consists of multiple rock types, which are often contacted by cross-cutting dykes. A total of 8 samples were collected from this area. C) A representation of the medium/fine-grained pink alkali-granites obtained from the Al Hafoor Suite. Note the relatively simple mineralogy of coarse quartz and alkali-feldspar with scattered black biotite and magnetite. D) A petrographic photograph taken in plane-polarised light of the same sample. Note the fine grained nature of the quartz and feldspar interrupted with green hastingsite and hornblende. E) The same petrographic photo taken in cross-polarised light. The location of all samples collected and a complementary catalogue of this suite is displayed in Figure 2.10 and Appendix 1.6 respectively.
337 Appendix 1.7: Afif Terrane samples collected from the Arabian Shield, Saudi Arabia (see Chapter 2.4, Figure 2.10 and Appendix 1.7.1 for location in the Shield and petrography respectively).
Sample Shield Published Geochronological Age Geological Map Unit Latitude Longitude Rock Type Field Mineralogy + Observations Name Terrane (Johnson, 2006) si114 210 31'00.24'' N 430 57'02.37'' E Rhyolite Medium-fine grey/black volcanics comprising the north trending Siham Group (si) Afif si116 210 31'00.93'' N 430 57'04.28'' E Rhyolite faulted belts in the southern part of the Afif terrane (spreads into the Poorly constrained by structural Nabitah Orogenic Belt). This suite ranges from rhyolitic/andesitic relationships suggesting 750-685Ma. volcanics through to shales and conglomerates. The matrix is presumably composed primarily of quartz and alkali-feldspar based on larger scattered crystals.
0 0 hla109 21 18'10.40'' N 43 51'18.31'' E Quartz-Monzonite This medium-coarse grained pink/grey/white coloured suite forms a The age of this suite is not fully 0 0 diverse batholith spread over the entire southern part of the Afif hla110 Haml Suite (hla) Afif 21 18'13.29'' N 43 51'21.78'' E Quartz-Monzonite constrained, but is dated at 640- 0 0 hla111 21 18'11.27'' N 43 51'22.06'' E Granite terrane. The mineralogy ranges from alkali-feldspar-quartz syenites hla112 0 0 Granite 625Ma (presumably U-Pb in zircon). 21 18'12.17'' N 43 51'21.03'' E through to plagioclase-hornlende-quartz granodiorties. Localised magma-mingling with micacious and amphibole rich enclaves is also observed scattered across the outcrops.
MCR104 210 08'50.34'' N 430 43'39.09'' E Basalt Medium-fine grained grey/black basalts forming undeformed north This has been directly dated by U-Pb Bani Ghayy Group (by) 0 0 MCR105 21 08'31.86'' N 43 44'05.65'' E Basalt trending belts spread across the Afif and Tathlith terranes and extend in zircon at 630-620Ma (rhyolite zircons). into the Nabitah Orogenic Belt. There is evidence of sedimentary shales, but the suite appears to be predominantly volcanics. The mineralogy is composed of plagioclase and green clinopyroxene. There are also green needles surrounding some pyroxene crystals, which is presumably actinolite reaction rims
338 Appendix 1.7 (continued): Afif Terrane samples collected from the Arabian Shield, Saudi Arabia (see Chapter 2.4, Figure 2.10 and Appendix 1.7.1 for location in the Shield and petrography respectively).
339 1.7.1 Haml Suite (hla). A mineralogical summary of this suite is presented in Chapter 2.4.
The Haml Suite is a large NW-SE trending suite composed of multiple subrectagular to subrounded granitic units, spread across the southern Afif terrane in the eastern area of the Shield. This unit comprises the Samim and Himarah Complexes (Johnson, 2006), which lie east of the Nabitah Orogenic Belt and are sandwiched between the Ruwah and Ar Rika Fault Zones. Although subtle differences in compositions separate the two units, geochronological boundaries are much more evident. As suggested by Johnson (2006), both are relatively undeformed and the Samim Complex is placed at 640-625Ma, whilst the Himarah Complex is <610Ma.
Weathered rounded outcrops were unexpectedly met with fresh sharp contact boundaries allowing ease of sampling (Figure A1.13). A total of 8 samples were collected here including granites, rhyolites and basalts (see Appendix 1.7). No evidence of mingling was observed, but sharp subvertical contacts with both the older Siham and Bani Ghayy Group volcanics were pronounced (Figure A1.13). These are quartz (50%), alkali-feldspar (~50%) and biotite <2%) rich rhyolites and clinopyroxene (60%) and plagioclase (~40%) rich basalts (Figure A1.12) respectively, but are not discussed further here.
White and pink, medium-coarse Haml Suite granite is mineralogically homogeneous and composed of alkali-feldspar (~50-60%), plagioclase (~30%), quartz (~10%), biotite and hornblende (<10%) that define quartz-monzonite/granite (Figure A1.12). Accessory phases include magnetite, zircon and apatite. Texturally, this is porphyritic defined by 1-5mm alkali-feldspar grains surrounded by finer (<1mm) quartz, feldspar, hornblende and biotite (Figure A1.13). Many of the alkali-feldspars are albite and orthoclase, but some large (2-5mm) patches of cumulate perthitic microcline are observed scattered between quartz grains (Figure A1.13). Coarse (1- 5mm) cumulate alkali-feldspar, quartz, microcline and plagioclase define the initial crystallisation phases. This is followed by fine (<1mm) alkali-feldspar, quartz and hornblende grains that fill the void spaces between the coarse alkali-feldspar and quartz crystals. Interstitial biotite occurs as one of the last stages of crystallisation and contains
340 no evidence of mineral inclusions. This is with the exception of possible subhedral <0.1mm zircon crystals observed in one grain.
Figure A1.12:A Plutonic classification scheme modified from De la Roche et al. (1980) of the Afif terrane. The Haml Suite (red circles) is a typical hypersolvous granitoids sandwiched between two orogenic suture zones. This intrudes the older volcanic country rocks (black squares) of the Siham (rhyolite) and Bani Ghayy (basalt) Groups.
Early formed euhedral-subhedral zircon crystals (<0.3mm in diameter) are relatively scarce and restricted to inclusions in quartz and feldspar crystals. Apatite is also observed at the intersections of quartz crystals. Magnetite is abundant and occurs predominantly as inclusions in hornblende. Mineralogically, this suite appears to be devoid of any Na-rich amphiboles or pyroxenes, but is coarsely perthitic, suggesting rapid exhumation.
341 Figure A1.13: A) Rounded low hills composed of Haml Suite quartz-monzonite near Afif, south of the Ar Rika Fault Zone. B) This suite intrudes the overlying Siham Group volcanics and exhibits a very sharp contact. A total of 8 samples were collected from this area. C) A representation of the medium/coarse-grained quartz-monzonite obtained from the Haml Suite. Note the relative equal abundance of both alkali-feldspar and plagioclase. D) A petrographic photograph taken in plane-polarised light of the same sample. Note the hornblende and interstitial biotite. E) The same petrographic photo taken in cross-polarised light. Note the large microcline crystals and absence of hypersolvous alkali-feldspar. The location of all samples collected and a complementary catalogue of this suite is displayed in Figure 2.10 and Appendix 1.7 respectively.
342 Appendix 1.8: Asir Terrane samples collected from the Arabian Shield, Saudi Arabia (see Chapter 2.4, Figure 2.10 and Chapter 2.3.3 for location in the Shield and petrography respectively).
Sample Shield Published Geochronological Age Geological Map Unit Latitude Longitude Rock Type Field Mineralogy + Observations Name Terrane (Johnson, 2006) kw 10 210 57'48.46'' N 420 15'35.09'' E Diorite kw 11 210 57'47.91'' N 420 15'34.74'' E Diorite kw 13 210 20'06.03'' N 420 47'70.85'' E Alkali-Granite kw 14 210 20'30.77'' N 42045'02.26'' E Gabbro kw 15 210 20'28.08'' N 42044'58.26'' E Gabbro Medium-coarse grained granites with a wide variety of coulours 0 0 kw 16 21 20'18.36'' N 42 44'58.89'' E Gabbro ranging from pink-white-grey through to green-purple. These granites 0 0 kw 18 21 19'59.47'' N 42 44'58.87'' E Gabbro are exposed by spectacular steeply dipping mountain ranges in the 0 0 kw 19 21 20'04.76'' N 42 44'56.78'' E Gabbro southern part of the Asir terrane and Nabitah Orogenic Belt. This suite 0 0 kw 21 21 20'10.17'' N 42 45'05.29'' E Alkali-Granite exhibits a wide range in granite compositions, but overall they consist 210 20'05.01'' N 420 45'03.95'' E kw 22 Alkali-Granite of quartz-alkali-feldspar-biotite assemblages with varying amounts of kw 23 210 20'05.69'' N 420 45'03.93'' E Alkali-Granite plagioclase-hornblende and green amphiboles (aegirine). This kw 24 210 20'05.02'' N 420 45'09.06'' E Alkali-Granite 0 0 undeformed suite contains many spectacular patches of magma- kw 29 21 07'19.15'' N 42 53'13.38'' E Alkali-Granite kw 30b 210 07'20.15'' N 420 53'20.48'' E Diorite mingling/layering interactions spread across exposed quarry faces. 0 0 kw 30p Kawr Suite (kw) Asir 21 07'20.15'' N 42 53'20.48'' E Alkali-Granite kw 31 210 07'20.19'' N 420 53'21.39'' E Alkali-Granite There are many grey/black mafic autoliths and cummulate layering This suite is not well constrained. It 0 0 kw 32 21 07'19.22'' N 42 53'22.13'' E Diorite patches scattered across the exposed quarry. These range from quartz- has a U-Pb in zircon age of 650- kw 33 210 07'19.19'' N 420 53'21.62'' E Diorite 605Ma. plagioclase-hornblende diorites, clinopyroxene-orthopyroxene kw 35 210 07'05.04' N 420 53'16.43' E Granite kw 36 210 07'03.48' N 420 53'19.01' E Alkali-Granite gabbroic-dolerites through to olivine-plagioclase gabbros. kw 38 210 06'59.40' N 420 53'16.73' E Alkali-Granite kw 40 200 18'33.89' N 420 41'49.36' E Alkali-Granite kw 41 200 18'34.60' N 420 41'50.61' E Alkali-Granite It is suspected that the cummulate layering of the more mafic units kw 42 200 18'33.64' N 420 41'49.02' E Granodiorite were settled out early in the fractionation process with 0 0 kw 43 20 18'34.53' N 42 41'49.13' E Gabbroic-Diorite extraction+fractionation of the remianing liquid giving rise to the kw 44 200 18'34.31'' N 420 41'48.54'' E Granite felisic granitic units. Such a spectular array of mafic-felsic interactions 0 0 kw 45 20 18'33.30'' N 42 41'48.80'' E Granite warrants extensive geochemical analysis. kw 46 200 18'22.49'' N 420 41'38.65' E Granite kw 50 200 18'21.94'' N 420 41'39.52'' E Granite kw 51b 200 18'20.72'' N 420 41'39.02'' E Granite
343 Appendix 1.8 (continued): Asir Terrane samples collected from the Arabian Shield, Saudi Arabia (see Chapter 2.4, Figure 2.10 and Chapter 2.3.3 (Kawr Suite) and Appendices 1.8.1-1.8.3 for location in the Shield and petrography respectively).
Sample Shield Published Geochronological Age Geological Map Unit Latitude Longitude Rock Type Field Mineralogy + Observations Name Terrane (Johnson, 2006) kw 51p 200 18'20.72'' N 420 41'39.02'' E Alkali-Granite kw 52b 200 18'21.19'' N 420 41'39.41'' E Granite Kawr Suite (kw) Asir See Previous Table See Previous Table kw 52p 200 18'21.19'' N 420 41'39.41'' E Alkali-Granite kw 55 200 18'21.01'' N 420 41'38.76'' E Diorite Medium-coarse grained pink granites forming a series of discordant 0 0 ih 66 19 29'16.02'' N 42 59'43.96'' E Alkali-Granite plutons in the southern part of the Asir terrane and Nabitah Orogenic This contains many units that have ih 68 190 29'13.91'' N 420 59'44.39'' E Alkali-Granite been dated at 641-617Ma Asir Belt. This suite ranges from pink quartz-alkali-feldspar-biotite rich ih 73 180 23'36.20'' N 420 53'17.75'' E Granite (presumably U-Pb in zircon). Ibn Hashbal Suite (ih) ih 74 180 23'35.93'' N 420 53'18.21'' E Granite microgranites to grey quartz-plagioclase-hornblende-biotite rich 0 0 ih 76 18 23'35.75'' N 42 53'17.71'' E Granite granites, but mingling appears to be absent. This suite is thought to have ih 79 180 23'36.05'' N 420 53'18.67'' E Granite coincided with the formation of the Kawr Suite due to thier geographical relationship.
hwg 03 210 26'59.00'' N 400 27'22.59'' E Granite Medium-fine grained red/pink granite forming subrectangular low relief This suite is poorly constrained hwg 04 Al Hawiyah Group 210 26'57.38' N 400 27'18.79'' E Quartz-Monzonite hills in the west central part of the Asir Terrane. The granite varies in with a combination Rb-Sr and 0 0 hwg 07 (hwg) Asir 21 26'54.04'' N 40 27'16.45'' E Granite grainsize and composition, but is predominantly quartz-alkali-feldspar SHRIMP ages of 630-590Ma. 0 0 hwg 08 21 27'26.99'' N 40 28'17.38' E Granite and biotite rich with minor plagioclase and brown/red titanite. Some hwg 09 210 27'26.81'' N 400 28'17.09' E Granite outrcops also contain patches of sulfides, which appear to be mostly pyrite. There is also evidence of magma-mingling with grey coloured intermediate autoliths scatterd across the outcrops. These are mostly composed of minerals similar to that of the granite, but contain hornblende-amphibole assemblages.
wb 61 190 26'51.74' N 420 49'52.97'' E Alkali-Granite Coarse grained white/pink granite forming a series of subrounded This suite is dated at 606Ma using 0 0 wb 62 19 26'59.31' N 42 49'54.28'' E Alkali-Granite plutons in the eastern part of the Asir Terrane and cross-cut the Nabitah SHRIMP. Wadbah Suite (wb) Asir 0 0 wb 63 19 26'57.46' N 42 49'58.05'' E Alkali-Granite Orogenic Belt. This suite is composed of quartz-alkali-feldspar- wb 65 190 27'09.68' N 420 49'58.70'' E Alkali-Granite hornblende with varying amounts of biotite and opaques. This suite also appears to have a similar geographical relationship with both the Kawr and Ibn Hashbal Suites.
344 Appendix 1.8 (continued): Asir Terrane samples collected from the Arabian Shield, Saudi Arabia (see Chapter 2.4, Figure 2.10 and Chapter 2.3.3 for location in the Shield and petrography respectively).
345 Appendix 1.8 (continued): Asir Terrane samples collected from the Arabian Shield, Saudi Arabia (see Chapter 2.4, Figure 2.10 and Chapter 2.3.3 for location in the Shield and petrography respectively).
346 Appendix 1.8 (continued): Asir Terrane samples collected from the Arabian Shield, Saudi Arabia (see Chapter 2.4, Figure 2.10 and Appendices 1.8.1-1.8.3 for location in the Shield and petrography respectively).
347 1.8.1 Ibn Hashbal Suite (ih). A mineralogical summary of this suite is presented in Chapter 2.4.
The Ibn Hashbal Suite forms a large N-S trending cluster of subrectagular- subrounded plutons confined to the Nabitah Orogenic Belt in the southeastern corner Asir terrane. This unit comprises the Bani Thawr, Tindahah, Thairwah and Najran plutons and the Jabal al Hasir and Jabal Ashirah Ring Complexes, which are lithologically categorised as one suite (Johnson, 2006). Individual units have been directly dated providing a broad suite age of 640-615Ma (Johnson, 2006), which is broadly coeval with the neighbouring Kawr Suite.
The undeformed, poorly exposed rounded outcrops were difficult to sample (Figure A1.14), but a total of 6 samples including 2 alkali-granites and 3 monzongranites were collected (see Appendix 1.8). No mingling contacts were exhibited, but a gradational mineralogical change from pink porphyritic granites to white equigranular monzongranites was observed. This primarily involved the reduction in pink alkali-feldspar and microcline and introduction of finer plagioclase and biotite.
Ibn Hashbal Suite units are typical hypersolvous samples composed of microcline + albite (~65%), quartz (~25%), hornblende (<10%) and biotite (<5%) that define an alkali-granite (Figure A1.15). Minor phases include plagioclase, hastingsite and magnetite. Textures range from equigranular to porphyritic with the latter characterised by coarse (5-10mm) perthitic microcline and quartz surrounded by finer (<1mm) quartz, albite and biotite (Figure A1.14). The majority of coarse feldspars are subhedral perthitic microcline with subhedral plagioclase and albite rarely seen.
Quartz crystallisation appears in two phases: initial coarse grains (5-10mm) of subhedral quartz; and fine (<1mm) interstitial anhedral quartz rimming the intersections of larger perthitic grains (Figure A1.14). Subhedral hornblende and interstitial biotite exclusively host magnetite inclusions. Hastingsite is rarely observed, but appears as inclusions in perthitic feldspars, presumably as an interstitial stage. This suite also contains samples that are composed of alkali-feldspar (~35%), plagioclase (~30%), quartz (~25%) and minor hornblende, biotite and titanite (~<10%) that define a granite composition (Figure A1.15).
348 1.8.2 Al Hawiyah Suite (hwg). A mineralogical summary of this suite is presented in Chapter 2.4.
The Al Hawiyah Suite is a term coined by Johnson (2006) for a group of subrectagular-subrounded discordant plutons in the western part of the Shield, southeast of Jeddah and At Ta’if. This suite comprises the Turabah Granite, Layyah Complex and Rahwah Granite, but are grouped based on lithological, geographical and geochronological similarities and has been poorly constrained at 630-590Ma. According to Johnson (2006), Rb-Sr ages vary across the suite, some bearing ages of 515Ma or even as low as 117Ma, but are thought to be singular anomalous dates.
Poorly exposed, rounded outcrops provided difficulties in obtaining samples. However, a total 5 fresh samples were obtained, including granodioritic autoliths (see Appendix 1.8). No evidence of deformation was observed, but sharp compositional changes between monzogabbroic and granitic units were seen scattered across the outcrops. These 10-20cm mafic autoliths are composed of plagioclase (~60%), hornblende (~15%), alkali-feldspar (<~15%), quartz (~10%) and clinopyroxene (~<5%), but are not discussed further here. Some felsic units contained <1mm sulphide veining (yellow-bluish), which is presumably pyrite or chalcopyrite
The pink granite is medium-coarse grained and mineralogically homogeneous. It is composed of alkali-feldspar, albite and microcline (~45%), quartz (~25-30%), plagioclase (~15%) and biotite (<10%) that define a granite (Figure A1.15). Accessory phases include magnetite, titanite and hastingsite. This granite contains porphyritic texture, defined by 10-20mm microcline surrounded by finer (1-5mm) quartz, alkali- feldspar, biotite and plagioclase grains (Figure A1.14). The interlocking network of perthitic albite and quartz fills the spaces between coarse euhedral perthitic grains (Figure A1.14). Perthite exclusively hosts the interstitial hastingsite inclusions. Quartz crystallisation occurs as two phases: initial 1-5mm subhedral quartz, alkali-feldspar and plagioclase; and rarely seen <1mm interstitial grains at mineral intersections. This appears to follow suit with biotite, but the earlier phases host the magnetite inclusions. Magnetite primarily occurs as inclusions in biotite, but also as a later phase sandwiched between quartz and biotite intersections. Interstitial euhedral titanite is rarely seen and exhibits textbook diamond shapes.
349 Figure A1.14: A) Rounded low hills composed of the Ibn Hashbal Suite alkali-granite near Khamis Mushayt, west of The Nabitah Orogenic Belt. A total of 6 samples were collected here. B) A representation of the alkali-granites collected. Note the large alkali-feldspar crystals. C) A petrographic photograph of the same granitic sample taken in plane-polarised light. Note the interstitial biotite/quartz patch in the centre. D) The same petrographic photo taken in cross- polarised light. Note the coarse perthitic feldspars, including microcline. E) Poorly exposed outcrops composed of the Al Hawiyah granite. A total of 5 samples were collected here including one mafic enclave. F) A representation of the coarse-grained granites obtained. Note the very coarse pink feldspars. G) A petrographic photograph taken in plane-polarised light of the same sample. Note the clear porphyritic nature of the granite. H) The same petrographic photo taken in cross-polarised light. Note the coarse microcline grain exhibiting microperthitic texture. The location of all samples collected and a complementary catalogue of this suite is displayed in Figure 2.10 and Appendix 1.8 respectively.
350 2.10.4 Wadbah Suite (wb). A mineralogical summary of this suite is presented in Chapter 2.4.
The Wadbah Suite is a collection of small rounded granitic plutons located ~50- 100km north of Abha in the southern part of the Asir terrane. These discordant undeformed plutons cross-cut the Nabitah Orogenic Belt south of the Ruwah Fault Zone (Figure A1.15). The granitic units have been directly dated at 606Ma (Johnson, 2006). The angular outcrops exposed by fresh road cuttings provided ample opportunity for sampling and a total of 4 samples were collected (see Appendix 1.8). No evidence of mingling was observed in the granitic units, but localised faulting produced grainsize reduction and an increase of hydrous biotite. This movement may be due to the vicinity of the Junaynah Fault Zone.
Fluctuations in biotite separate the mineralogically and texturally homogeneous pink plutons composed of perthite (~65%), quartz (~25%), plagioclase (~5%) and biotite (~5%) that define an alkali-granite (Figure A1.15). Minor phases include hornblende, microcline and magnetite. Textures are equigranular characterised by coarse (5-10mm) perthitic feldspars and quartz (Figure A1.15). However, minor patches of interstitial biotite and quartz often create a porphyritic style texture sandwiched between large perthitic feldspars. Although perthite dominates the feldspar mineralogy, there are rare occurrences of early euhedral-subhedral plagioclase and microcline (Figure A1.15). Euhedral hornblende is also occasionally seen and contains textbook 60-1200 cleavage intersections and exclusively host magnetite grains. Euhedral-subhedral <0.2mm zircon crystals were also only confined to perthitic feldspars.
351 Figure A1.15: A) Exposed low hills (foreground) composed of the Wadbah Suite alkali-granite near Khamis Mushayt, west of the Nabitah Orogenic Belt (mountain). A total of 4 samples were collected here. B) A representation of the alkali-granites obtained. C) A petrographic photograph taken in plane- polarised light of the same sample. Note the coarse nature and interstitial biotite. D) The same petrographic photo taken in cross-polarised light. Note the textbook examples of perthitic texture in feldspar grains. E)A Plutonic classification scheme modified from De la Roche et al. (1980) of the Asir terrane. The Al Hawiyah (yellow circles), Ibn Hashbal (red circles) and Wadbah (blue circles) are Na-rich ferromagnesian hypersolvous or A-type granites. These can be geochemically discriminated as discussed further in Chapter 7. The location of all samples collected and a complementary catalogue of this suite is displayed in Figure 2.10 and Appendix 1.8 respectively.
352 Appendix 2: Zircon U-Pb Geochronological Data
353 Island Arc Magmatism (~950-750 Ma) Pre-Arabian Shield Assembly
354 Table 1: U-Pb isotope data from Makkah Suite (dm) zircon grains analysed by LA-ICPMS (Appendix a1). The isotope data has been subdivided into 3 groups based on their zircon morphology and 1σ error from the total mean of the suite, n=38 (Chapter 6). These values have been numerically arranged to highlight the maximum and minimum values. Consequently, the spot numbers are no longer in subsequent experimental time. However, spot numbers 1-13, 14-25 and 26-38 correspond to Block 1 (GJ standards 1-7), Block 2 (GJ standards 6-12) and Block 3 (GJ Standards 11-17) respectively (see standard Table 1-continued). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ 207Pb/206Pb ±1σ 206Pb/238U ±1σ 207Pb/235U ±1σ 208Pb/232Th ±1σ Conc. σ from No. (Ma) (Ma) (Ma) (Ma) mean Makkah Suite (dm)-sample dm01a, n=38 Group1 Spot13 0.06780 0.00176 0.14572 0.00231 1.36187 0.03595 0.04024 0.00265 862.4 53.0 876.9 13.0 872.7 15.5 797.5 51.4 102 2.41 Spot10 0.06856 0.00162 0.14507 0.00236 1.37117 0.03437 0.03766 0.00277 885.4 48.2 873.3 13.3 876.7 14.7 747.1 54.0 99 2.08 Spot2 0.07074 0.00121 0.14497 0.00209 1.41368 0.02657 0.03938 0.00139 949.8 34.6 872.7 11.8 894.7 11.2 780.6 26.9 92 2.30 Spot32 0.06761 0.00108 0.14433 0.00208 1.34523 0.02419 0.04181 0.00135 856.7 32.7 869.1 11.7 865.5 10.5 827.9 26.2 101 2.00 Spot16 0.06850 0.00176 0.14408 0.00229 1.36070 0.03566 0.04032 0.00343 883.6 52.2 867.7 12.9 872.2 15.3 798.9 66.6 98 1.71 Spot33 0.06792 0.00095 0.14345 0.00203 1.34315 0.02212 0.04159 0.00138 866.2 28.7 864.1 11.4 864.6 9.6 823.5 26.8 100 1.62 Spot17 0.06713 0.00163 0.14281 0.00223 1.32170 0.03314 0.03952 0.00326 841.7 49.9 860.6 12.6 855.3 14.5 783.5 63.4 102 1.19 Spot14 0.06699 0.00149 0.14240 0.00218 1.31515 0.03066 0.03875 0.00301 837.4 45.7 858.2 12.3 852.4 13.5 768.5 58.6 102 1.02 Group2 Spot25 0.06851 0.00181 0.14198 0.00227 1.34108 0.03605 0.03919 0.00350 883.9 53.6 855.9 12.8 863.7 15.6 776.9 68.1 97 0.80 Spot11 0.06793 0.00140 0.14197 0.00209 1.32940 0.02878 0.03990 0.00241 866.4 42.1 855.8 11.8 858.6 12.6 790.7 46.9 99 0.86 Spot26 0.06691 0.00090 0.14176 0.00196 1.30772 0.02083 0.04067 0.00118 835.0 27.8 854.6 11.1 849.1 9.2 805.7 22.9 102 0.81 Spot7 0.06773 0.00103 0.14158 0.00203 1.32212 0.02322 0.03727 0.00144 860.5 31.4 853.6 11.4 855.4 10.2 739.5 28.1 99 0.70 Spot1 0.06616 0.00092 0.14156 0.00198 1.29112 0.02108 0.03659 0.00113 811.3 28.8 853.5 11.2 841.8 9.3 726.4 22.1 105 0.70 Spot23 0.06732 0.00176 0.14136 0.00224 1.31202 0.03502 0.03789 0.00349 847.6 53.6 852.4 12.7 851.0 15.4 751.8 68.0 101 0.53 Spot21 0.06711 0.00171 0.14108 0.00224 1.30537 0.03400 0.03782 0.00319 841.2 52.1 850.8 12.6 848.1 15.0 750.2 62.2 101 0.41 Spot27 0.06562 0.00096 0.14081 0.00196 1.27389 0.02129 0.04084 0.00130 794.4 30.3 849.2 11.1 834.1 9.5 809.1 25.2 107 0.32 Spot4 0.07024 0.00126 0.14049 0.00206 1.36045 0.02671 0.03870 0.00144 935.3 36.5 847.4 11.7 872.1 11.5 767.5 28.0 91 0.15 Spot8 0.06632 0.00110 0.14048 0.00204 1.28454 0.02398 0.03726 0.00150 816.6 34.4 847.4 11.5 838.9 10.7 739.4 29.3 104 0.15 Spot9 0.06636 0.00105 0.14013 0.00202 1.28211 0.02310 0.03710 0.00152 817.9 32.6 845.4 11.5 837.8 10.3 736.3 29.7 103 -0.02 Spot22 0.06713 0.00204 0.14009 0.00239 1.29658 0.03948 0.03649 0.00375 841.8 61.9 845.1 13.5 844.2 17.5 724.4 73.2 100 -0.04 Spot12 0.07370 0.00137 0.13986 0.00207 1.42097 0.02872 0.04200 0.00208 1033.2 37.0 843.9 11.7 897.8 12.0 831.5 40.3 82 -0.15 Spot6 0.06657 0.00117 0.13982 0.00206 1.28335 0.02493 0.03634 0.00147 824.5 36.1 843.6 11.7 838.3 11.1 721.4 28.7 102 -0.17 Spot5 0.06835 0.00102 0.13946 0.00198 1.31419 0.02262 0.03756 0.00137 879.3 30.6 841.6 11.2 852.0 9.9 745.3 26.7 96 -0.36 Spot36 0.06826 0.00108 0.13932 0.00200 1.31099 0.02339 0.04074 0.00160 876.5 32.4 840.8 11.3 850.6 10.3 807.1 31.2 96 -0.43 Spot30 0.06599 0.00094 0.13914 0.00197 1.26577 0.02117 0.03948 0.00119 806.1 29.7 839.8 11.2 830.5 9.5 782.7 23.1 104 -0.52 Spot35 0.06618 0.00094 0.13881 0.00196 1.26633 0.02100 0.04099 0.00153 812.1 29.4 837.9 11.1 830.7 9.4 812.0 29.8 103 -0.70 Spot19 0.07105 0.00207 0.13824 0.00231 1.35415 0.03958 0.03933 0.00339 958.8 58.4 834.7 13.1 869.3 17.1 779.7 65.9 87 -0.84
355 Table 1: U-Pb isotope data from Makkah Suite (dm) zircon grains analysed by LA-ICPMS (Appendix a1). The isotope data has been subdivided into 3 groups based on their zircon morphology and 1σ error from the total mean of the suite, n=38 (Chapter 6). These values have been numerically arranged to highlight the maximum and minimum values. Consequently, the spot numbers are no longer in subsequent experimental time. However, spot numbers 1-13, 14-25 and 26-38 correspond to Block 1 (GJ standards 1-7), Block 2 (GJ standards 6-12) and Block 3 (GJ Standards 11-17) respectively (see standard Table 1-continued). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ 207Pb/206Pb ±1σ 206Pb/238U ±1σ 207Pb/235U ±1σ 208Pb/232Th ±1σ Conc. σ from No. (Ma) (Ma) (Ma) (Ma) mean Makkah Suite (dm)-sample dm01a, n=38 Group3 Spot37 0.06626 0.00100 0.13815 0.00196 1.26189 0.02174 0.04132 0.00169 814.7 31.2 834.2 11.1 828.8 9.8 818.5 32.9 102 -1.03 Spot24 0.06984 0.00253 0.13811 0.00255 1.32986 0.04752 0.03907 0.00475 923.6 72.8 834.0 14.5 858.8 20.7 774.6 92.5 90 -0.81 Spot29 0.06878 0.00107 0.13808 0.00197 1.30924 0.02313 0.04090 0.00124 892.1 31.9 833.8 11.2 849.8 10.2 810.2 24.1 93 -1.06 Spot15 0.06673 0.00158 0.13800 0.00214 1.26959 0.03111 0.03813 0.00308 829.3 48.6 833.4 12.1 832.2 13.9 756.3 60.0 100 -1.01 Spot3 0.06737 0.00110 0.13787 0.00198 1.28065 0.02341 0.03578 0.00129 849.4 33.5 832.6 11.2 837.1 10.4 710.5 25.1 98 -1.16 Spot38 0.06669 0.00108 0.13764 0.00198 1.26541 0.02298 0.04075 0.00173 828.3 33.5 831.3 11.2 830.3 10.3 807.3 33.6 100 -1.28 Spot31 0.06796 0.00093 0.13760 0.00194 1.28916 0.02096 0.04015 0.00126 867.4 28.2 831.1 11.0 840.9 9.3 795.7 24.4 96 -1.32 Spot20 0.06721 0.00165 0.13759 0.00215 1.27495 0.03221 0.03747 0.00315 844.3 50.3 831.0 12.2 834.6 14.4 743.4 61.5 98 -1.20 Spot18 0.06664 0.00182 0.13740 0.00219 1.26236 0.03488 0.03729 0.00361 826.6 56.1 829.9 12.4 829.0 15.7 740.0 70.4 100 -1.26 Spot34 0.06751 0.00108 0.13547 0.00195 1.26082 0.02278 0.03931 0.00143 853.6 33.0 819.0 11.1 828.3 10.2 779.4 27.8 96 -2.40 Spot28 0.06737 0.00097 0.13483 0.00188 1.25220 0.02075 0.04057 0.00129 849.1 29.5 815.4 10.7 824.4 9.4 803.9 25.1 96 -2.83
dm Mean, n=38 842.6 5.3 (±1σ) MSWD=1.5 Group1 Mean,n=8 867.0 11 (±1σ) MSWD=0.18 U-Pb Concordia (isoptope ratios): Groups seperated based on σ from mean Group2 Mean,n=19 847.2 5.3 (±1σ) MSWD=0.30 Group3 Mean,n=11 828.7 9 (±1σ) MSWD=0.37
dm Mean, n=38 845.6 4.9 [0.58%] MSWD=1.6 Group1 Mean,n=8 Weighted Av. (assigned internal errors) 95% conf. 1.96σ: Groups seperated based on σ 867.6 8.5 [0.98%] MSWD=0.27 Group2 Mean,n=19 from mean 847.0 5.3 [0.62%] MSWD=0.29 Group3 Mean,n=11 829.2 6.8 [0.83%] MSWD=0.29
Group1 Isoplot age unmix 839.0 6.0 (±2σ) [0.67%] Gaussian Distribution (2σ)-assigned 1σ internal errors relative misfit=0.986 Group2 Isoplot age unmix 857.4 9.2 (±2σ) [0.37%]
356 Table 1 (continued): U-Pb absolute age data for zircon standards analysed by LA-ICPMS (Appendix a1). These standards have recognised age values (see Jackson et al., 2004 and Slama et al, 2008) and are used to tie the unknown zircon values by linear modelling (GJ standards provide error bounds on unknown values) and check internal accuracy (ples) respectively. Block 1 (GJ standards 1-7), Block 2 (GJ standards 6-12) and Block 3 (GJ Standards 11-17) correspond to absolute age values 1-13, 14-25 and 26-38 respectively (see dm ages Table 1). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 206Pb/238U 207Pb/235U 208Pb/232Th 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ ±1σ ±1σ ±1σ ±1σ Conc. No. (Ma) (Ma) (Ma) (Ma) Makkah Suite (dm)-sample dm01a, n=38 GJ GJ1 0.06018 0.00104 0.09982 0.00144 0.82827 0.01576 0.03096 0.00168 610.2 37.0 613.4 8.4 612.7 8.8 616.4 33.0 101 GJ2 0.05957 0.00106 0.09696 0.00140 0.79627 0.01549 0.03236 0.00181 587.9 38.2 596.6 8.2 594.7 8.8 643.8 35.5 101 GJ3 0.06002 0.00108 0.09727 0.00141 0.80480 0.01578 0.02994 0.00174 604.1 38.4 598.4 8.3 599.5 8.9 596.4 34.2 99 GJ4 0.06105 0.00101 0.09664 0.00137 0.81344 0.01494 0.02992 0.00156 641.1 35.3 594.7 8.1 604.4 8.4 595.9 30.6 93 GJ5 0.06014 0.00104 0.09695 0.00138 0.80371 0.01526 0.02953 0.00166 608.5 37.1 596.5 8.1 598.9 8.6 588.3 32.7 98 GJ6 0.06052 0.00132 0.09743 0.00149 0.81295 0.01867 0.03354 0.00264 622.2 46.4 599.3 8.8 604.1 10.5 666.7 51.7 96 GJ7 0.05940 0.00151 0.09803 0.00154 0.80277 0.02082 0.02969 0.00289 581.8 54.2 602.8 9.0 598.4 11.7 591.3 56.8 104 GJ8 0.06005 0.00135 0.09792 0.00150 0.81065 0.01909 0.02948 0.00242 605.3 48.0 602.2 8.8 602.8 10.7 587.3 47.6 99 GJ9 0.06050 0.00156 0.09700 0.00153 0.80910 0.02128 0.03094 0.00301 621.5 54.7 596.8 9.0 602.0 11.9 616.0 59.0 96 GJ10 0.05978 0.00171 0.09729 0.00159 0.80181 0.02314 0.03105 0.00319 595.0 61.4 598.5 9.3 597.8 13.0 618.1 62.5 101 GJ11 0.06030 0.00181 0.09824 0.00164 0.81680 0.02457 0.03039 0.00329 614.4 63.7 604.1 9.6 606.3 13.7 605.1 64.6 98 GJ12 0.06000 0.00091 0.09664 0.00137 0.79944 0.01388 0.03300 0.00149 603.4 32.5 594.7 8.0 596.5 7.8 656.2 29.2 99 GJ13 0.05957 0.00090 0.09760 0.00138 0.80165 0.01386 0.03192 0.00145 588.0 32.3 600.3 8.1 597.8 7.8 635.2 28.4 102 GJ14 0.06076 0.00098 0.09746 0.00137 0.81645 0.01464 0.03050 0.00160 630.8 34.3 599.5 8.1 606.1 8.2 607.3 31.3 95 GJ15 0.05978 0.00098 0.09700 0.00137 0.79942 0.01455 0.03147 0.00167 595.1 35.6 596.8 8.1 596.5 8.2 626.2 32.7 100 GJ16 0.05892 0.00107 0.09812 0.00141 0.79697 0.01569 0.02913 0.00189 564.3 39.1 603.4 8.3 595.1 8.9 580.5 37.1 107 GJ17 0.06134 0.00122 0.09732 0.00142 0.82298 0.01729 0.03375 0.00244 651.3 42.1 598.7 8.4 609.7 9.6 670.9 47.7 92 GJ Mean 607.0 19 [2σ] 599.7 4.0 [2σ] 601.1 4.4 [2σ] Weighted Av. 95% conf. (1.96σ) GJ Mean (GEMOC) 607.7 4.3 [2σ] 600.7 1.1[2σ] 602.0 1.0 [2σ] Plesovic ples1 0.05374 0.00075 0.05594 0.00077 0.41445 0.00675 0.01478 0.00048 359.9 31.3 350.9 4.7 352.1 4.9 296.6 9.5 97 ples2 0.05296 0.00075 0.05635 0.00078 0.41147 0.00677 0.01523 0.00050 327.2 31.9 353.4 4.7 349.9 4.9 305.4 10.0 108 ples3 0.05323 0.00127 0.05559 0.00085 0.40795 0.01004 0.01756 0.00151 338.5 53.2 348.8 5.2 347.4 7.2 351.9 30.0 103 ples4 0.05419 0.00126 0.05606 0.00086 0.41883 0.01007 0.01698 0.00140 379.0 51.3 351.6 5.2 355.2 7.2 340.2 27.8 93 ples5 0.05296 0.00072 0.05582 0.00077 0.40757 0.00654 0.01708 0.00050 326.9 30.4 350.2 4.7 347.1 4.7 342.3 10.0 107 ples6 0.05325 0.00072 0.05618 0.00078 0.41248 0.00659 0.01708 0.00050 339.4 30.1 352.4 4.8 350.7 4.7 342.3 10.0 104 Ples Mean 341.0 28 [2σ] 351.3 3.9 [2σ) 350.2 4.2 [2σ] Weighted Av. 95% conf. (1.96σ) Ples Mean (Slama et al., 2008) 339.2 0.25 [2σ] 337.1 0.37 [2σ] 337.3 0.11 [2σ]
357 Syncollisional Magmatism (~736-636 Ma) Arabian Shield Microplate Accretion and Suture Formation
358 Table 2: U-Pb isotope data from Shufayyah Complex (su) zircon grains analysed by LA-ICPMS (Appendix a1). The isotope data has been subdivided into 3 groups based on their zircon morphology and 1σ error from the total mean of the suite, n=47 (Chapter 6). These values have been numerically arranged to highlight the maximum and minimum values. Consequently, the spot numbers are no longer in subsequent experimental time. However, spot numbers 1-11, 12-20, 21-33 and 34-47 correspond to Block 1 (GJ standards 1-7), Block 2 (GJ standards 6-12), Block 3 (GJ Standards 11-17) and Block 4 (GJ Standards 16- 22) respectively (see standard Table 2-continued). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 1σ 206Pb/238U1σ 207Pb/235U 1σ 208Pb/232Th 1σ 207Pb/206Pb ±1σ 206Pb/238U ±1σ 207Pb/235U ±1σ 208Pb/232Th ±1σ Conc. σ from No. (Ma) (Ma) (Ma) (Ma) mean Shufayyah Complex (su)-sample su215, n=47 Group1 Spot20 0.06279 0.00116 0.12037 0.00183 1.04195 0.02127 0.03498 0.00108 701.1 39.0 732.7 10.5 724.9 10.6 694.9 21.1 105 1.64 Spot21 0.06302 0.00121 0.12030 0.00185 1.04522 0.02192 0.03426 0.00111 708.9 40.3 732.3 10.7 726.5 10.9 680.8 21.6 103 1.58 Spot32 0.06081 0.00127 0.12024 0.00188 1.00804 0.02261 0.03753 0.00165 632.4 44.4 731.9 10.8 707.9 11.4 744.8 32.1 116 1.52 Spot37 0.06330 0.00267 0.12012 0.00249 1.04822 0.04340 0.03168 0.00348 718.3 87.1 731.3 14.4 728.0 21.5 630.3 68.2 102 1.11 Spot5 0.06484 0.00087 0.12009 0.00163 1.07329 0.01682 0.03659 0.00116 769.1 28.0 731.1 9.4 740.4 8.2 726.4 22.7 95 1.67 Spot15 0.06370 0.00159 0.11995 0.00191 1.05350 0.02710 0.03611 0.00273 731.6 52.1 730.3 11.0 730.6 13.4 717.0 53.2 100 1.35 Spot16 0.06248 0.00179 0.11985 0.00198 1.03256 0.02990 0.04021 0.00392 690.7 59.9 729.7 11.4 720.2 14.9 796.8 76.2 106 1.25 Spot22 0.06037 0.00115 0.11984 0.00187 0.99746 0.02102 0.03419 0.00115 616.9 40.7 729.6 10.8 702.5 10.7 679.4 22.6 118 1.32 Spot45 0.06164 0.00172 0.11967 0.00206 1.01703 0.02901 0.03352 0.00291 661.7 58.7 728.7 11.8 712.4 14.6 666.3 56.8 110 1.12 Group2 Spot34 0.06282 0.00157 0.11916 0.00199 1.03197 0.02684 0.03424 0.00251 702.1 52.4 725.7 11.4 719.9 13.4 680.4 49.1 103 0.90 Spot31 0.06551 0.00196 0.11904 0.00217 1.07522 0.03266 0.03258 0.00197 790.7 61.4 725.1 12.5 741.3 16.0 648.0 38.5 92 0.77 Spot19 0.06309 0.00182 0.11894 0.00200 1.03451 0.03024 0.03462 0.00304 711.2 60.0 724.5 11.5 721.2 15.1 687.9 59.4 102 0.79 Spot2 0.06315 0.00126 0.11886 0.00172 1.03484 0.02160 0.03479 0.00121 713.4 41.7 724.0 9.9 721.3 10.8 691.2 23.7 101 0.86 Spot30 0.06448 0.00114 0.11886 0.00181 1.05661 0.02091 0.03641 0.00135 757.3 36.9 724.0 10.5 732.2 10.3 722.8 26.3 96 0.82 Spot36 0.06368 0.00143 0.11867 0.00189 1.04188 0.02477 0.03581 0.00255 731.0 47.0 722.9 10.9 724.9 12.3 711.2 49.8 99 0.69 Spot23 0.06281 0.00132 0.11848 0.00185 1.02592 0.02310 0.03460 0.00126 701.7 44.2 721.8 10.7 716.9 11.6 687.5 24.7 103 0.60 Spot46 0.06007 0.00174 0.11829 0.00202 0.97970 0.02877 0.03597 0.00318 606.1 61.3 720.7 11.7 693.5 14.8 714.3 62.1 119 0.45 Spot18 0.06295 0.00153 0.11817 0.00189 1.02566 0.02594 0.03547 0.00278 706.6 50.8 720.0 10.9 716.8 13.0 704.5 54.2 102 0.42 Spot17 0.06315 0.00149 0.11800 0.00186 1.02744 0.02538 0.03832 0.00302 713.4 49.5 719.1 10.7 717.6 12.7 760.0 58.8 101 0.34 Spot43 0.06283 0.00166 0.11792 0.00197 1.02138 0.02771 0.03445 0.00272 702.4 55.2 718.6 11.4 714.6 13.9 684.7 53.1 102 0.28 Spot42 0.06153 0.00221 0.11786 0.00224 0.99973 0.03570 0.03516 0.00398 657.8 75.2 718.2 12.9 703.7 18.1 698.5 77.7 109 0.21 Spot28 0.06479 0.00168 0.11768 0.00201 1.05127 0.02829 0.03196 0.00149 767.5 53.8 717.2 11.6 729.5 14.0 635.8 29.1 93 0.15 Spot7 0.06563 0.00138 0.11765 0.00177 1.06444 0.02359 0.03495 0.00153 794.7 43.3 717.0 10.2 736.0 11.6 694.4 29.8 90 0.15 Spot41 0.06319 0.00193 0.11758 0.00209 1.02435 0.03164 0.03357 0.00319 714.7 63.6 716.6 12.1 716.1 15.9 667.3 62.4 100 0.10 Spot25 0.06467 0.00119 0.11756 0.00182 1.04825 0.02143 0.03639 0.00130 763.7 38.3 716.5 10.5 728.0 10.6 722.4 25.4 94 0.10 Spot27 0.06361 0.00110 0.11751 0.00180 1.03068 0.02017 0.03632 0.00134 728.8 36.3 716.2 10.4 719.3 10.1 721.0 26.2 98 0.07 Spot8 0.06242 0.00130 0.11742 0.00177 1.01041 0.02238 0.03204 0.00130 688.7 44.0 715.7 10.2 709.1 11.3 637.4 25.4 104 0.03 Spot40 0.06170 0.00166 0.11725 0.00199 0.99749 0.02763 0.03396 0.00286 663.9 56.7 714.7 11.5 702.5 14.0 675.0 56.0 108 -0.06
359 Table 2 (continued): U-Pb isotope data from Shufayyah Complex (su) zircon grains analysed by LA-ICPMS (Appendix a1). The isotope data has been subdivided into 3 groups based on their zircon morphology and 1σ error from the total mean of the suite, n=47 (Chapter 6). These values have been numerically arranged to highlight the maximum and minimum values. Consequently, the spot numbers are no longer in subsequent experimental time. However, spot numbers 1-11, 12-20, 21-33 and 34-47 correspond to Block 1 (GJ standards 1-7), Block 2 (GJ standards 6-12), Block 3 (GJ Standards 11-17) and Block 4 (GJ Standards 16-22) respectively (see standard Table 2-continued). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ 207Pb/206Pb ±1σ 206Pb/238U ±1σ 207Pb/235U ±1σ 208Pb/232Th ±1σ Conc. σ from No. (Ma) (Ma) (Ma) (Ma) mean Shufayyah Complex (su)-sample su215, n=47 Group2 Spot40 0.06170 0.00166 0.11725 0.00199 0.99749 0.02763 0.03396 0.00286 663.9 56.7 714.7 11.5 702.5 14.0 675.0 56.0 108 -0.06 Spot10 0.06542 0.00149 0.11713 0.00183 1.05648 0.02504 0.03500 0.00228 787.8 47.1 714.0 10.6 732.1 12.4 695.3 44.6 91 -0.14 Spot9 0.06322 0.00151 0.11704 0.00183 1.02019 0.02506 0.03554 0.00230 715.6 49.9 713.5 10.6 714.0 12.6 705.8 45.0 100 -0.18 Spot24 0.06421 0.00129 0.11705 0.00182 1.03621 0.02245 0.03573 0.00130 748.6 41.8 713.5 10.5 722.0 11.2 709.7 25.5 95 -0.18 Spot39 0.06391 0.00177 0.11680 0.00201 1.02910 0.02919 0.03262 0.00260 738.5 57.6 712.1 11.6 718.5 14.6 648.9 51.0 96 -0.29 Spot38 0.06306 0.00191 0.11665 0.00198 1.01428 0.03078 0.03656 0.00372 710.4 63.0 711.2 11.4 711.0 15.5 725.8 72.6 100 -0.37 Spot6 0.06301 0.00141 0.11641 0.00178 1.01117 0.02360 0.03140 0.00130 708.5 46.8 709.9 10.3 709.5 11.9 624.9 25.4 100 -0.54 Spot35 0.06341 0.00171 0.11627 0.00198 1.01649 0.02821 0.03441 0.00275 722.1 56.2 709.1 11.5 712.1 14.2 683.8 53.7 98 -0.55 Spot29 0.06259 0.00213 0.11576 0.00221 0.99889 0.03402 0.02641 0.00174 694.3 70.8 706.1 12.8 703.2 17.3 526.9 34.2 102 -0.73 Spot47 0.06183 0.00183 0.11573 0.00201 0.98656 0.02959 0.03718 0.00343 668.3 62.1 705.9 11.6 697.0 15.1 737.8 66.8 106 -0.82 Spot44 0.06045 0.00266 0.11527 0.00246 0.96045 0.04120 0.02156 0.00265 619.7 92.3 703.3 14.2 683.5 21.3 431.1 52.5 113 -0.85 Group3 Spot1 0.06299 0.00096 0.11549 0.00154 1.00273 0.01673 0.03397 0.00092 707.7 32.0 704.5 8.9 705.2 8.5 675.2 18.1 100 -1.23 Spot14 0.06578 0.00169 0.11493 0.00187 1.04246 0.02751 0.03489 0.00270 799.5 52.9 701.3 10.8 725.1 13.7 693.2 52.8 88 -1.31 Spot26 0.06010 0.00172 0.11463 0.00207 0.94979 0.02790 0.01967 0.00118 607.1 60.9 699.6 12.0 678.0 14.5 393.6 23.4 115 -1.32 Spot12 0.06426 0.00224 0.11454 0.00213 1.01492 0.03511 0.02930 0.00294 750.4 72.0 699.1 12.3 711.4 17.7 583.7 57.7 93 -1.33 Spot33 0.06062 0.00188 0.11418 0.00210 0.95411 0.03000 0.02578 0.00159 625.6 65.4 697.0 12.1 680.2 15.6 514.4 31.4 111 -1.52 Spot11 0.06346 0.00220 0.11383 0.00211 0.99576 0.03422 0.02946 0.00304 723.7 71.9 694.9 12.2 701.7 17.4 586.8 59.6 96 -1.68 Spot13 0.06535 0.00166 0.11364 0.00186 1.02403 0.02681 0.03426 0.00272 785.7 52.5 693.9 10.8 715.9 13.5 680.9 53.2 88 -2.00 Spot3 0.06463 0.00168 0.11261 0.00174 1.00290 0.02643 0.03500 0.00211 762.3 53.9 687.9 10.1 705.3 13.4 695.2 41.2 90 -2.72 Spot4 0.06444 0.00153 0.11252 0.00181 0.99958 0.02471 0.02613 0.00126 756.1 49.4 687.3 10.5 703.6 12.6 521.3 24.8 91 -2.68
su Mean, n=47 715.8 3.2(±1σ) MSWD=1.09 Group1 Mean,n=9 731.1 9.1 (±1σ) MSWD=0.016 U-Pb Concordia (isoptope ratios): Groups seperated based on σ from mean Group2 Mean,n=29 716.7 4.2 (±1σ) MSWD=0.26 Group3 Mean,n=9 697.4 7.9 (±1σ) MSWD=0.34
su Mean, n=47 715.4 3.6 [0.50%] MSWD=1.2 Group1 Mean,n=9 Weighted Av. (assigned internal errors) 95% conf. 1.96σ: Groups seperated based on σ from 730.9 7.2 [0.98%] MSWD=0.015 Group2 Mean,n=29 mean 716.7 4.1 [0.57%] MSWD=0.015 Group3 Mean,n=9 696.3 7.1 [1.0%] MSWD=0.34
Group1 Isoplot age unmix 697.2 16 (±2σ) [0.16%] Gaussian Distribution (2σ)-assigned 1σ internal errors relative misfit=0.991 Group2 Isoplot age unmix 717.9 4.3 (±2σ) [0.88%]
360 Table 2 (continued): U-Pb absolute age data for zircon standards analysed by LA-ICPMS (Appendix a1). These have recognised values (see Jackson et al., 2004 and Slama et al, 2008), which are used to tie the unknown zircon values by linear modelling (standards provide error bounds on unknown values). Block 1 (GJ standards 1-7), Block 2 (GJ standards 6-12), Block 3 (GJ Standards 11-17) and Block 4 (GJ Standards 16-22) correspond to absolute age values 1-11, 12-20, 21-33 and 34-47 respectively (see su ages Table 2). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis No. 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ 207Pb/206Pb ±1σ 206Pb/238U ±1σ 207Pb/235U ±1σ 208Pb/232Th ±1σ Conc. (Ma) (Ma) (Ma) (Ma) Shufayyah Complex (su)-sample su215, n=47 GJ Standard GJ1 0.06102 0.00083 0.09808 0.00122 0.82548 0.01218 0.03201 0.00127 640.1 28.8 603.1 7.2 611.1 6.8 636.8 24.8 94 GJ2 0.05980 0.00081 0.09819 0.00123 0.80976 0.01205 0.03105 0.00124 596.4 29.2 603.8 7.2 602.3 6.8 618.1 24.4 101 GJ3 0.05989 0.00084 0.09611 0.00123 0.79359 0.01223 0.02964 0.00125 599.6 30.0 591.6 7.2 593.2 6.9 590.4 24.6 99 GJ4 0.05960 0.00131 0.09693 0.00146 0.79640 0.01808 0.03089 0.00233 589.0 46.8 596.4 8.6 594.8 10.2 614.8 45.7 101 GJ5 0.06052 0.00115 0.09753 0.00142 0.81376 0.01644 0.03172 0.00196 622.2 40.6 599.9 8.3 604.6 9.2 631.1 38.5 96 GJ6 0.06029 0.00116 0.09821 0.00144 0.81627 0.01668 0.03032 0.00192 613.8 41.1 603.9 8.4 606.0 9.3 603.7 37.7 98 GJ7 0.05961 0.00128 0.09820 0.00147 0.80709 0.01805 0.03120 0.00236 589.5 45.9 603.9 8.6 600.8 10.1 621.0 46.3 102 GJ8 0.05954 0.00133 0.09802 0.00148 0.80466 0.01863 0.03045 0.00245 586.9 47.9 602.8 8.7 599.5 10.5 606.3 48.1 103 GJ9 0.06044 0.00142 0.09768 0.00156 0.81389 0.02017 0.03076 0.00268 619.4 49.9 600.8 9.2 604.6 11.3 612.3 52.6 97 GJ10 0.06014 0.00152 0.09729 0.00158 0.80657 0.02127 0.03116 0.00305 608.6 53.8 598.5 9.3 600.5 12.0 620.1 59.7 98 GJ11 0.05942 0.00093 0.09836 0.00142 0.80561 0.01446 0.02963 0.00148 582.6 33.6 604.8 8.3 600.0 8.1 590.2 29.1 104 GJ12 0.06033 0.00100 0.09690 0.00145 0.80591 0.01526 0.03180 0.00166 615.5 35.4 596.2 8.6 600.2 8.6 632.7 32.6 97 GJ13 0.06029 0.00090 0.09761 0.00143 0.81129 0.01422 0.02967 0.00141 614.0 31.8 600.4 8.4 603.2 8.0 591.0 27.7 98 GJ14 0.05929 0.00088 0.09843 0.00144 0.80450 0.01412 0.03158 0.00140 577.7 32.1 605.2 8.5 599.4 8.0 628.4 27.5 105 GJ15 0.06033 0.00091 0.09778 0.00144 0.81318 0.01441 0.03105 0.00143 615.4 32.4 601.4 8.4 604.2 8.1 618.0 28.0 98 GJ16 0.05972 0.00124 0.09729 0.00152 0.80102 0.01783 0.03054 0.00219 593.6 44.1 598.5 8.9 597.4 10.1 608.0 43.0 101 GJ17 0.06078 0.00137 0.09846 0.00154 0.82510 0.01954 0.03074 0.00247 631.3 47.8 605.4 9.1 610.9 10.9 611.9 48.5 96 GJ18 0.06005 0.00134 0.09748 0.00153 0.80707 0.01897 0.03021 0.00239 605.3 47.4 599.6 9.0 600.8 10.7 601.6 46.9 99 GJ19 0.05968 0.00141 0.09765 0.00155 0.80354 0.01980 0.03216 0.00272 592.8 49.8 600.6 9.1 598.8 11.2 639.9 53.3 101 GJ20 0.05966 0.00137 0.09735 0.00154 0.80083 0.01932 0.03115 0.00257 591.4 49.1 598.9 9.1 597.3 10.9 620.1 50.3 101 GJ21 0.06053 0.00148 0.09750 0.00160 0.81368 0.02070 0.03070 0.00261 622.6 51.9 599.8 9.4 604.5 11.6 611.1 51.2 96 GJ22 0.06009 0.00172 0.09751 0.00165 0.80785 0.02351 0.02978 0.00323 607.0 60.7 599.8 9.7 601.2 13.2 593.1 63.4 99 GJ Mean 606.0 16 [2σ] 600.7 3.6 [2σ] 601.7 3.8 [2σ] Weighted Av. 95% conf. (1.96σ) GJ Mean (GEMOC) 607.7 4.3 [2σ] 600.7 1.1[2σ] 602.0 1.0 [2σ] Plesovice ples1 0.05470 0.00070 0.05371 0.00067 0.40515 0.00576 0.01908 0.00047 400.1 27.9 337.3 4.1 345.4 4.2 382.1 9.4 84 ples2 0.05294 0.00067 0.05315 0.00067 0.38792 0.00554 0.01677 0.00042 326.0 28.5 333.8 4.1 332.9 4.1 336.1 8.3 102 ples3 0.05311 0.00119 0.05506 0.00082 0.40322 0.00927 0.01764 0.00125 333.6 49.9 345.5 5.0 344.0 6.7 353.4 24.9 104 ples4 0.05470 0.00085 0.05422 0.00078 0.40881 0.00730 0.01718 0.00060 400.1 33.8 340.4 4.8 348.0 5.3 344.3 12.0 85 ples5 0.05308 0.00083 0.05448 0.00078 0.39858 0.00715 0.01755 0.00063 332.0 35.0 342.0 4.8 340.6 5.2 351.6 12.5 103 ples6 0.05426 0.00129 0.05339 0.00084 0.39942 0.00987 0.01722 0.00137 381.8 52.4 335.3 5.2 341.2 7.2 345.0 27.2 88 ples7 0.05266 0.00130 0.05408 0.00086 0.39264 0.00997 0.01813 0.00150 314.0 54.9 339.5 5.2 336.3 7.3 363.1 29.8 108 ples8 0.05267 0.00094 0.05463 0.00094 0.39639 0.00852 0.01887 0.00091 314.8 39.9 342.9 5.8 339.0 6.2 377.9 18.1 109 Ples Mean 356.0 25 [2σ] 338.7 3.5 [2σ) 340.9 5.4 [2σ] Weighted Av. 95% conf. (1.96σ) Ples Mean (Slama et al., 2008) 339.2 0.25 [2σ] 337.1 0.37 [2σ] 337.3 0.11 [2σ]
361 Table 3: U-Pb isotope data from Jar-Salajah Complex and Fara’ Trondhjemite (js) zircon grains analysed by LA-ICPMS (Appendix a1). The isotope data has been subdivided into 3 groups based on their zircon morphology and 1σ error from the total mean of the suite, n=29 (Chapter 6). These values have been numerically arranged to highlight the maximum and minimum values. Consequently, the spot numbers are no longer in subsequent experimental time. However, spot numbers 1-13, 14-22 and 23-39 correspond to Block 1 (GJ standards 1-7), Block 2 (GJ standards 6-12) and Block 3 (GJ Standards 11-17) respectively (see standard Table 3-continued). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis No. 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ 207Pb/206Pb ±1σ 206Pb/238U ±1σ 207Pb/235U ±1σ 208Pb/232Th ±1σ Conc. σ from (Ma) (Ma) (Ma) (Ma) mean Jar-Salajah Complex (js)-sample js202, n=29 Group1 Spot3 0.06329 0.00092 0.11818 0.00148 1.03123 0.01604 0.03797 0.00105 718.1 30.4 720.1 8.5 719.5 8.0 753.2 20.4 100 3.16 Spot8 0.06355 0.00096 0.11810 0.00151 1.03474 0.01678 0.03856 0.00120 726.7 31.7 719.6 8.7 721.3 8.4 764.6 23.4 99 3.04 Spot18 0.06352 0.00141 0.11727 0.00164 1.02687 0.02301 0.03774 0.00263 725.7 46.3 714.9 9.5 717.4 11.5 748.7 51.3 99 2.30 Spot22 0.06376 0.00145 0.11691 0.00165 1.02751 0.02368 0.03634 0.00267 733.8 47.6 712.7 9.6 717.7 11.9 721.4 52.1 97 2.05 Spot19 0.06248 0.00136 0.11669 0.00163 1.00503 0.02216 0.03833 0.00263 690.5 45.7 711.5 9.4 706.4 11.2 760.4 51.3 103 1.95 Spot25 0.06326 0.00115 0.11618 0.00162 1.01310 0.01946 0.03327 0.00127 716.9 38.0 708.5 9.3 710.4 9.8 661.5 24.8 99 1.64 Spot27 0.06349 0.00096 0.11603 0.00150 1.01574 0.01652 0.03732 0.00116 724.7 31.6 707.7 8.7 711.8 8.3 740.5 22.5 98 1.68 Spot2 0.06227 0.00096 0.11591 0.00144 0.99507 0.01609 0.03726 0.00111 683.5 32.5 707.0 8.3 701.3 8.2 739.4 21.5 103 1.66 Spot14 0.06237 0.00136 0.11592 0.00159 0.99670 0.02186 0.03715 0.00249 686.7 45.8 707.0 9.2 702.1 11.1 737.3 48.5 103 1.50 Spot21 0.06247 0.00139 0.11556 0.00163 0.99515 0.02249 0.03484 0.00246 690.2 46.9 705.0 9.4 701.3 11.5 692.3 48.1 102 1.26 Spot9 0.06286 0.00105 0.11550 0.00147 1.00095 0.01744 0.03876 0.00140 703.5 35.2 704.6 8.5 704.3 8.9 768.6 27.3 100 1.34 Spot5 0.06321 0.00094 0.11512 0.00145 1.00318 0.01600 0.03654 0.00107 715.2 31.4 702.4 8.4 705.4 8.1 725.3 21.0 98 1.10 Group2 Spot13 0.06303 0.00099 0.11453 0.00148 0.99532 0.01669 0.03757 0.00137 709.3 33.0 699.0 8.5 701.4 8.5 745.5 26.7 99 0.68 Spot4 0.06319 0.00091 0.11420 0.00144 0.99493 0.01552 0.03522 0.00098 714.6 30.4 697.1 8.3 701.2 7.9 699.6 19.2 98 0.47 Spot20 0.06270 0.00136 0.11307 0.00157 0.97724 0.02154 0.03578 0.00250 698.1 45.6 690.5 9.1 692.2 11.1 710.5 48.8 99 -0.29 Spot12 0.06395 0.00102 0.11303 0.00146 0.99661 0.01698 0.03772 0.00139 740.0 33.5 690.3 8.5 702.1 8.6 748.5 27.0 93 -0.34 Spot26 0.06281 0.00090 0.11281 0.00144 0.97689 0.01527 0.03493 0.00101 701.8 30.2 689.0 8.4 692.0 7.8 693.9 19.7 98 -0.50 Group3 Spot29 0.06219 0.00097 0.11205 0.00145 0.96075 0.01610 0.03481 0.00124 680.5 33.1 684.7 8.4 683.7 8.3 691.6 24.2 101 -1.00 Spot17 0.06408 0.00134 0.11202 0.00155 0.98950 0.02113 0.03700 0.00241 744.3 43.6 684.4 9.0 698.5 10.8 734.4 46.9 92 -0.98 Spot10 0.06344 0.00097 0.11174 0.00143 0.97735 0.01607 0.03622 0.00122 723.1 32.2 682.8 8.3 692.2 8.3 719.1 23.8 94 -1.25 Spot1 0.06528 0.00137 0.11148 0.00161 1.00344 0.02186 0.03626 0.00158 783.5 43.6 681.4 9.4 705.6 11.1 719.8 30.7 87 -1.26 Spot7 0.06553 0.00130 0.11122 0.00157 1.00477 0.02075 0.03550 0.00159 791.4 41.0 679.8 9.1 706.2 10.5 705.0 31.0 86 -1.47 Spot23 0.06487 0.00117 0.11109 0.00154 0.99346 0.01900 0.03519 0.00124 770.2 37.6 679.1 8.9 700.5 9.7 699.1 24.3 88 -1.57 Spot24 0.06438 0.00126 0.11075 0.00145 0.98300 0.01947 0.03566 0.00146 754.0 40.8 677.1 8.4 695.1 10.0 708.2 28.6 90 -1.91 Spot11 0.06170 0.00117 0.10987 0.00141 0.93455 0.01789 0.03579 0.00171 663.7 40.1 672.0 8.2 670.0 9.4 710.7 33.4 101 -2.59 Spot6 0.06504 0.00173 0.10959 0.00173 0.98247 0.02642 0.03549 0.00222 775.5 55.0 670.4 10.0 694.9 13.5 704.8 43.4 86 -2.27 Spot15 0.06466 0.00128 0.10958 0.00148 0.97685 0.01975 0.03676 0.00226 763.4 41.0 670.3 8.6 692.0 10.1 729.7 44.1 88 -2.65 Spot16 0.06290 0.00128 0.10945 0.00150 0.94914 0.01972 0.03358 0.00210 705.0 42.6 669.6 8.7 677.7 10.3 667.5 41.2 95 -2.71 Spot28 0.06329 0.00172 0.10820 0.00172 0.94401 0.02584 0.03129 0.00192 717.9 56.8 662.3 10.0 675.0 13.5 622.7 37.7 92 -3.09
js Mean, n=29 705.9 7 (±1σ) MSWD=1.4 Group1 Mean,n=12 13 (±1σ) MSWD=0.26 U-Pb Concordia (isoptope ratios): Groups seperated based on σ from mean 710.0 Group2 Mean,n=5 694.0 12 (±1σ) MSWD=0.37 Group3 Mean,n=12 674.5 9.4 (±1σ) MSWD=0.65
js Mean, n=29 693.2 6.3 [0.71%] MSWD=3.5 Group1 Mean,n=12 Weighted Av. (assigned internal errors) 95% conf. 1.96σ: Groups seperated based on σ from 710.0 5 [0.98%] MSWD=0.44 Group2 Mean,n=5 mean 693.2 7.5 [1.1%] MSWD=0.28 Group3 Mean,n=12 676.5 5 [0.74%] MSWD=0.60 Group1 Isoplot age unmix 679.3 5.3 (±2σ) [0.50%] Group2 Isoplot age unmix Gaussian Distribution (2σ)-assigned 1σ internal errors 707.3 5.5 (±2σ) [0.50%] relative misfit=0.850
362 Table 3 (continued): U-Pb absolute age data for zircon standards analysed by LA-ICPMS (Appendix a1). These standards have recognised age values (see Jackson et al., 2004 and Slama et al, 2008), which are used to tie the unknown zircon values by linear modelling (standards provide error bounds on unknown values). Block 1 (GJ standards 1-7), Block 2 (GJ standards 6-12) and Block 3 (GJ Standards 11-17) correspond to absolute age values 1-13, 14-22 and 23-29 respectively (see js ages Table 3). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 206Pb/238U 207Pb/235U 208Pb/232Th 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ ±1σ ±1σ ±1σ ±1σ Conc. No. (Ma) (Ma) (Ma) (Ma) Jar-Salajah Complex (js)-sample js202, n=29 GJ GJ1 0.06002 0.00079 0.09780 0.00121 0.80921 0.01177 0.03118 0.00112 604.3 28.3 601.5 7.1 602.0 6.6 620.7 21.9 100 GJ2 0.05973 0.00085 0.09813 0.00124 0.80813 0.01253 0.03105 0.00126 594.0 30.6 603.5 7.3 601.4 7.0 618.0 24.7 102 GJ3 0.06013 0.00085 0.09847 0.00123 0.81630 0.01251 0.03169 0.00129 608.3 30.3 605.4 7.2 606.0 7.0 630.6 25.3 100 GJ4 0.05975 0.00113 0.09725 0.00129 0.80119 0.01556 0.02979 0.00194 594.4 40.8 598.3 7.6 597.5 8.8 593.3 38.1 101 GJ5 0.06008 0.00111 0.09842 0.00131 0.81521 0.01558 0.03058 0.00191 606.3 39.5 605.2 7.7 605.4 8.7 608.9 37.5 100 GJ6 0.06072 0.00121 0.09742 0.00130 0.81550 0.01649 0.03140 0.00217 629.3 42.3 599.2 7.6 605.5 9.2 624.8 42.5 95 GJ7 0.05981 0.00133 0.09722 0.00134 0.80166 0.01785 0.03222 0.00254 596.9 47.4 598.1 7.9 597.8 10.1 641.0 49.7 100 GJ8 0.05989 0.00125 0.09893 0.00136 0.81677 0.01736 0.02988 0.00219 599.4 44.6 608.1 8.0 606.2 9.7 595.1 43.0 101 GJ9 0.06115 0.00142 0.09697 0.00138 0.81736 0.01910 0.03022 0.00248 644.6 49.0 596.6 8.1 606.6 10.7 601.8 48.7 93 GJ10 0.05957 0.00144 0.09837 0.00141 0.80773 0.01955 0.03096 0.00267 588.0 51.5 604.9 8.3 601.2 11.0 616.3 52.4 103 GJ11 0.05951 0.00081 0.09726 0.00123 0.79797 0.01201 0.03094 0.00118 585.7 29.3 598.4 7.2 595.7 6.8 615.9 23.1 102 GJ12 0.06035 0.00081 0.09841 0.00124 0.81873 0.01216 0.03011 0.00114 616.0 28.6 605.1 7.3 607.3 6.8 599.7 22.3 98 GJ13 0.06048 0.00080 0.09817 0.00124 0.81856 0.01207 0.03193 0.00114 620.8 28.3 603.7 7.3 607.2 6.7 635.2 22.4 97 GJ14 0.06004 0.00082 0.09681 0.00122 0.80139 0.01203 0.02988 0.00116 605.0 29.3 595.7 7.2 597.6 6.8 595.1 22.7 98 GJ15 0.06000 0.00086 0.09844 0.00126 0.81431 0.01278 0.03040 0.00128 603.6 30.6 605.2 7.4 604.9 7.2 605.2 25.1 100 GJ16 0.05950 0.00093 0.09711 0.00125 0.79662 0.01330 0.03142 0.00150 585.3 33.6 597.4 7.4 594.9 7.5 625.2 29.4 102 GJ17 0.06076 0.00095 0.09819 0.00127 0.82267 0.01371 0.03022 0.00146 630.9 33.3 603.8 7.4 609.5 7.6 601.8 28.7 96 GJ Mean 606.0 16 [2σ] 601.7 3.6 [2σ] 602.7 3.3 [2σ] Weighted Av. 95% conf. (1.96σ) GJ Mean (GEMOC) 607.7 4.3 [2σ] 600.7 1.1[2σ] 602.0 1.0 [2σ] Plesovice ples1 0.05288 0.00068 0.05323 0.00065 0.38809 0.00552 0.01741 0.00043 323.7 28.8 334.3 4.0 333.0 4.0 348.9 8.5 103 ples2 0.05509 0.00069 0.05387 0.00066 0.40914 0.00571 0.01976 0.00046 415.6 27.4 338.3 4.0 348.3 4.1 395.5 9.1 81 ples3 0.05505 0.00103 0.05457 0.00072 0.41424 0.00795 0.02154 0.00129 414.3 40.9 342.5 4.4 351.9 5.7 430.8 25.6 83 ples4 0.05620 0.00104 0.05400 0.00072 0.41845 0.00803 0.02108 0.00122 459.6 40.8 339.0 4.4 354.9 5.8 421.7 24.2 74 ples5 0.05287 0.00067 0.05458 0.00068 0.39784 0.00571 0.01815 0.00044 323.2 28.6 342.6 4.2 340.1 4.2 363.5 8.8 106 ples6 0.05283 0.00066 0.05494 0.00069 0.40017 0.00568 0.01810 0.00042 321.6 28.2 344.8 4.2 341.8 4.1 362.6 8.3 107 Ples Mean 365.0 60 [2σ] 340.1 3.4 [2σ) 343.3 8.2 [2σ] Weighted Av. 95% conf. (1.96σ) Ples Mean (Slama et al., 2008) 339.2 0.25 [2σ] 337.1 0.37 [2σ] 337.3 0.11 [2σ]
363 Table 4: U-Pb isotope data from Subh Suite (sf) zircon grains analysed by LA-ICPMS (Appendix a1). These values have been numerically arranged to highlight the maximum and minimum values. Consequently, the spot numbers are no longer in subsequent experimental time. However, spot numbers 1-11 and 12-22 correspond to Block 1 (GJ standards 1-7) and Block 2 (GJ standards 6-12) respectively (see standard Table 4-continued). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ 207Pb/206Pb ±1σ 206Pb/238U ±1σ 207Pb/235U ±1σ 208Pb/232Th ±1σ Conc. σ from No. (Ma) (Ma) (Ma) (Ma) mean Subh Suite (sf)-sample sf209, n=22 Spot 20 0.06221 0.00216 0.11627 0.00237 0.99714 0.03547 0.03351 0.00404 681.4 72.4 709.1 13.7 702.4 18.0 666.3 79.0 104 0.76 Spot 22 0.06532 0.00217 0.11595 0.00235 1.04413 0.03577 0.03535 0.00388 784.7 68.3 707.2 13.6 726.0 17.8 702.2 75.8 90 0.62 Spot 12 0.06205 0.00175 0.11572 0.00215 0.98974 0.02964 0.04199 0.00347 675.8 59.3 705.9 12.4 698.6 15.1 831.4 67.2 104 0.58 Spot 7 0.06302 0.00116 0.11563 0.00201 1.00475 0.02198 0.03558 0.00147 708.9 38.8 705.4 11.6 706.2 11.1 706.7 28.6 100 0.57 Spot 18 0.06334 0.00385 0.11562 0.00311 1.00950 0.05984 0.03506 0.00749 719.6 124.1 705.3 18.0 708.6 30.2 696.4 146.3 98 0.36 Spot 15 0.06319 0.00298 0.11534 0.00274 1.00472 0.04700 0.02486 0.00348 714.5 97.2 703.7 15.8 706.2 23.8 496.3 68.6 98 0.31 Spot 10 0.06081 0.00142 0.11531 0.00220 0.96665 0.02512 0.02076 0.00095 632.5 49.6 703.5 12.7 686.7 13.0 415.2 18.8 111 0.37 Spot 2 0.06445 0.00184 0.11517 0.00224 1.02328 0.03088 0.02837 0.00135 756.5 59.0 702.7 12.9 715.6 15.5 565.5 26.5 93 0.31 Spot 19 0.06460 0.00259 0.11508 0.00256 1.02500 0.04122 0.02518 0.00287 761.4 82.3 702.2 14.8 716.4 20.7 502.7 56.5 92 0.23 Spot 3 0.06209 0.00186 0.11473 0.00217 0.98195 0.03056 0.04089 0.00271 677.1 62.9 700.1 12.5 694.6 15.7 810.1 52.6 103 0.11 Spot 16 0.06518 0.00396 0.11456 0.00312 1.02906 0.06080 0.03139 0.00632 780.1 122.8 699.2 18.1 718.5 30.4 624.8 123.9 90 0.03 Spot 4 0.06389 0.00130 0.11452 0.00201 1.00877 0.02346 0.03492 0.00143 737.9 42.4 698.9 11.7 708.3 11.9 693.8 28.0 95 0.01 Spot 13 0.06225 0.00210 0.11440 0.00233 0.98174 0.03414 0.03239 0.00348 682.6 70.6 698.2 13.5 694.5 17.5 644.2 68.2 102 -0.04 Spot 5 0.06451 0.00167 0.11429 0.00220 1.01633 0.02861 0.02659 0.00131 758.5 53.8 697.6 12.7 712.1 14.4 530.4 25.7 92 -0.09 Spot 21 0.06255 0.00210 0.11419 0.00229 0.98478 0.03401 0.03539 0.00380 693.1 70.0 697.0 13.2 696.1 17.4 703.0 74.1 101 -0.13 Spot 6 0.06501 0.00138 0.11365 0.00201 1.01869 0.02440 0.03535 0.00149 774.6 44.1 693.9 11.7 713.3 12.3 702.2 29.0 90 -0.42 Spot 8 0.06058 0.00130 0.11362 0.00200 0.94904 0.02283 0.03714 0.00178 624.3 45.5 693.7 11.6 677.6 11.9 737.0 34.7 111 -0.44 Spot 1 0.06344 0.00141 0.11351 0.00202 0.99273 0.02455 0.03814 0.00172 723.0 46.4 693.1 11.7 700.1 12.5 756.6 33.4 96 -0.48 Spot 9 0.06282 0.00121 0.11325 0.00196 0.98095 0.02193 0.03476 0.00155 702.2 40.5 691.6 11.4 694.1 11.2 690.6 30.3 98 -0.63 Spot 14 0.06260 0.00290 0.11315 0.00266 0.97647 0.04483 0.02709 0.00353 694.6 95.7 691.0 15.4 691.8 23.0 540.2 69.4 99 -0.50 Spot 11 0.06393 0.00138 0.11287 0.00209 0.99468 0.02449 0.02699 0.00137 739.2 45.0 689.4 12.1 701.1 12.5 538.2 27.1 93 -0.77 Spot 17 0.06472 0.00462 0.11236 0.00345 1.00244 0.06908 0.02432 0.00456 765.1 143.7 686.4 20.0 705.0 35.0 485.7 90.0 90 -0.62
sf Mean, n=22 U-Pb Concordia (isoptope ratios): Groups seperated based on σ from mean 699.1 5.8 (±1σ) MSWD=0.21
Weighted Av. (assigned internal errors) 95% conf. 1.96σ: Groups seperated based on σ sf Mean, n=22 698.7 5.5 [0.79%] MSWD=0.21 from mean
364 Table 4 (continued): U-Pb absolute age data for zircon standards analysed by LA-ICPMS (Appendix a1). These standards have recognised age values (see Jackson et al., 2004 and Slama et al, 2008), which are used to tie the unknown zircon values by linear modelling (standards provide error bounds on unknown values). Block 1 (GJ standards 1-7) and Block 2 (GJ standards 6-12) correspond to absolute age values 1-11 and 12-22 respectively (see sf ages Table 4). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 206Pb/238U 207Pb/235U 208Pb/232Th 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ ±1σ ±1σ ±1σ ±1σ Conc. No. (Ma) (Ma) (Ma) (Ma) Subh Suite (sf)-sample sf209, n=22 GJ GJ1 0.06033 0.00092 0.09834 0.00159 0.81780 0.01554 0.03157 0.00151 615.3 32.6 604.7 9.4 606.8 8.7 628.3 29.6 98 GJ2 0.05972 0.00092 0.09866 0.00158 0.81230 0.01543 0.03317 0.00158 593.7 32.9 606.6 9.3 603.7 8.6 659.5 31.0 102 GJ3 0.06025 0.00094 0.09855 0.00159 0.81856 0.01570 0.02855 0.00147 612.5 33.5 605.9 9.3 607.2 8.8 568.9 29.0 99 GJ4 0.05988 0.00103 0.09569 0.00156 0.78994 0.01607 0.02830 0.00168 599.1 36.7 589.1 9.2 591.1 9.1 564.0 33.0 98 GJ5 0.06044 0.00102 0.09522 0.00157 0.79355 0.01610 0.03204 0.00179 619.4 36.2 586.3 9.2 593.2 9.1 637.4 35.0 95 GJ6 0.06217 0.00236 0.09840 0.00195 0.84347 0.03201 0.03579 0.00573 679.9 79.1 605.0 11.5 621.1 17.6 710.7 111.9 89 GJ7 0.06081 0.00179 0.09817 0.00183 0.82323 0.02521 0.02808 0.00342 632.7 62.3 603.7 10.7 609.8 14.0 559.7 67.2 95 GJ8 0.05910 0.00146 0.09756 0.00178 0.79498 0.02136 0.03006 0.00256 570.9 53.0 600.1 10.5 594.0 12.1 598.6 50.2 105 GJ9 0.05945 0.00163 0.09751 0.00181 0.79916 0.02321 0.03142 0.00325 583.5 58.4 599.8 10.6 596.4 13.1 625.3 63.8 103 GJ10 0.06033 0.00169 0.09609 0.00178 0.79927 0.02358 0.02964 0.00318 615.4 59.2 591.5 10.5 596.4 13.3 590.4 62.4 96 GJ11 0.06035 0.00193 0.09847 0.00191 0.81937 0.02718 0.03307 0.00401 616.2 67.7 605.5 11.2 607.7 15.2 657.5 78.4 98 GJ12 0.06012 0.00191 0.09722 0.00189 0.80581 0.02647 0.02926 0.00346 607.8 67.1 598.1 11.1 600.1 14.9 582.9 67.9 98 GJ Mean 608.0 25 [2σ] 599.4 5.7 [2σ] 601.1 6.2 [2σ] Weighted Av. 95% conf. (1.96σ) GJ Mean (GEMOC) 607.7 4.3 [2σ] 600.7 1.1[2σ] 602.0 1.0 [2σ] Plesovice ples1 0.05170 0.00074 0.05463 0.00088 0.38941 0.00714 0.01772 0.00054 272.0 32.6 342.9 5.4 333.9 5.2 354.9 10.8 126 ples2 0.05362 0.00083 0.05353 0.00087 0.39575 0.00762 0.01710 0.00062 355.0 34.8 336.2 5.3 338.6 5.5 342.7 12.3 95 ples3 0.05483 0.00152 0.05534 0.00101 0.41832 0.01220 0.02480 0.00256 405.2 60.1 347.2 6.2 354.8 8.7 495.2 50.5 86 ples4 0.05175 0.00150 0.05522 0.00102 0.39394 0.01192 0.02058 0.00223 274.1 65.0 346.5 6.2 337.2 8.7 411.8 44.1 126 Ples Mean 318.0 92 [2σ] 342.6 5.6 [2σ) 339.0 12 [2σ] Weighted Av. 95% conf. (1.96σ) Ples Mean (Slama et al., 2008) 339.2 0.25 [2σ] 337.1 0.37 [2σ] 337.3 0.11 [2σ]
365 Post-Orogenic Magmatism (~636-600 Ma) Post-Arabian Shield Terrane Accretion
366 Table 5: U-Pb isotope data from Kawr Suite (kw) zircon grains analysed by LA-ICPMS (Appendix a1). The isotope data has been subdivided into 3 groups based on their zircon morphology and 1σ error from the total mean of the suite, n=26 (Chapter 6). These values have been numerically arranged to highlight the maximum and minimum values. Consequently, the spot numbers are no longer in subsequent experimental time. However, spot numbers 1-7, 8-16 and 17- 26 correspond to Block 1 (GJ standards 1-7), Block 2 (GJ standards 6-12) and Block 3 (GJ Standards 11-17) respectively (see standard Table 5-continued). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ 207Pb/206Pb ±1σ 206Pb/238U ±1σ 207Pb/235U ±1σ 208Pb/232Th ±1σ Conc. σ from No. (Ma) (Ma) (Ma) (Ma) mean Kawr Suite (kw-sample kw42, n=26 Group1 Spot2 0.06153 0.00248 0.10576 0.00251 0.89597 0.03663 0.02320 0.00170 657.8 84.1 648.1 14.6 649.6 19.6 463.5 33.5 99 2.49 Spot25 0.05968 0.00060 0.10500 0.00166 0.86380 0.01348 0.03061 0.00038 592.7 21.1 643.7 9.7 632.2 7.4 609.4 7.5 109 3.31 Spot11 0.05864 0.00175 0.10498 0.00202 0.84875 0.02665 0.03831 0.00391 553.8 63.9 643.6 11.8 624.0 14.6 759.9 76.0 116 2.71 Spot13 0.05905 0.00426 0.10445 0.00323 0.84937 0.05983 0.02173 0.00542 569.0 149.6 640.4 18.8 624.3 32.9 434.5 107.3 113 1.52 Spot24 0.06267 0.00063 0.10310 0.00162 0.89071 0.01384 0.03031 0.00033 697.2 21.3 632.6 9.5 646.8 7.4 603.5 6.5 91 2.20 Spot4 0.05893 0.00211 0.10279 0.00232 0.83409 0.03070 0.01745 0.00134 564.4 76.2 630.7 13.6 615.9 17.0 349.7 26.6 112 1.40 Spot12 0.06101 0.00338 0.10253 0.00272 0.86192 0.04710 0.02321 0.00380 639.6 114.8 629.2 15.9 631.2 25.7 463.8 75.0 98 1.10 Spot3 0.06436 0.00120 0.10164 0.00189 0.90166 0.02061 0.03073 0.00157 753.5 38.8 624.0 11.1 652.6 11.0 611.8 30.8 83 1.11 Group2 Spot5 0.06053 0.00218 0.10116 0.00231 0.84316 0.03089 0.01636 0.00121 622.5 76.0 621.2 13.5 620.9 17.0 328.0 24.0 100 0.70 Spot9 0.06245 0.00344 0.10064 0.00267 0.86550 0.04682 0.02026 0.00320 689.6 113.4 618.2 15.7 633.1 25.5 405.5 63.4 90 0.41 Spot21 0.06236 0.00062 0.09991 0.00141 0.85895 0.01201 0.03342 0.00037 686.4 21.2 613.9 8.3 629.6 6.6 664.4 7.2 89 0.26 Spot7 0.06200 0.00200 0.09982 0.00218 0.85283 0.02856 0.01937 0.00138 674.3 67.5 613.3 12.8 626.2 15.7 387.8 27.3 91 0.12 Spot6 0.06131 0.00121 0.09971 0.00181 0.84279 0.01959 0.03204 0.00168 650.3 41.8 612.7 10.6 620.7 10.8 637.5 33.0 94 0.09 Spot19 0.06255 0.00062 0.09967 0.00144 0.85957 0.01222 0.02820 0.00028 693.1 20.9 612.5 8.4 629.9 6.7 562.1 5.5 88 0.09 Spot10 0.06016 0.00187 0.09904 0.00188 0.82145 0.02640 0.04038 0.00483 609.3 65.7 608.8 11.0 608.9 14.7 800.2 93.9 100 -0.26 Spot17 0.06174 0.00253 0.09903 0.00198 0.84296 0.03402 0.03113 0.00422 665.2 85.5 608.7 11.6 620.8 18.7 619.7 82.7 92 -0.26 Spot23 0.06007 0.00059 0.09879 0.00147 0.81814 0.01201 0.03019 0.00031 606.1 21.2 607.3 8.6 607.0 6.7 601.2 6.0 100 -0.51 Spot22 0.06268 0.00065 0.09847 0.00139 0.85088 0.01204 0.03437 0.00048 697.5 22.0 605.5 8.2 625.1 6.6 683.1 9.3 87 -0.76 Spot15 0.06037 0.00083 0.09830 0.00152 0.81825 0.01423 0.02635 0.00064 617.0 29.4 604.4 9.0 607.1 7.9 525.7 12.6 98 -0.82 Spot14 0.06311 0.00272 0.09809 0.00210 0.85346 0.03669 0.04254 0.00701 712.0 89.1 603.2 12.3 626.5 20.1 842.0 135.9 85 -0.69 Group3 Spot26 0.06069 0.00060 0.09756 0.00139 0.81632 0.01146 0.02934 0.00034 628.1 21.1 600.1 8.2 606.0 6.4 584.5 6.6 96 -1.42 Spot18 0.06412 0.00124 0.09753 0.00158 0.86213 0.01867 0.03491 0.00236 745.6 40.3 599.9 9.3 631.3 10.2 693.5 46.0 80 -1.27 Spot8 0.06203 0.00158 0.09649 0.00178 0.82519 0.02272 0.03490 0.00294 675.2 53.6 593.8 10.4 610.9 12.6 693.4 57.4 88 -1.72 Spot16 0.06015 0.00131 0.09638 0.00177 0.79926 0.01961 0.02024 0.00113 608.8 46.5 593.2 10.4 596.4 11.1 404.9 22.3 97 -1.78 Spot1 0.06250 0.00203 0.09568 0.00212 0.82288 0.02821 0.02530 0.00200 691.3 67.8 589.1 12.5 609.7 15.7 505.1 39.4 85 -1.81 Spot20 0.06349 0.00063 0.09564 0.00141 0.83716 0.01219 0.02998 0.00030 724.8 20.8 588.8 8.3 617.6 6.7 597.1 5.9 81 -2.75
kw Mean, n=26 618.0 7.1 (±1σ) MSWD=1.9 Group1 Mean,n=8 8.2 (±1σ) MSWD=0.26 U-Pb Concordia (isoptope ratios): Groups seperated based on σ from mean 636.6 Group2 Mean,n=12 609.8 9.2 (±1σ) MSWD=0.25 Group3 Mean,n=6 596.0 15 (±1σ) MSWD=0.26
kw Mean, n=26 611.7 6.5 [1.1%] MSWD=2.4 Group1 Mean,n=8 Weighted Av. (assigned internal errors) 95% conf. 1.96σ: Groups seperated based on σ from 636.3 8.4 [1.3%] MSWD=0.49 Group2 Mean,n=12 mean 609.9 5.7 [0.94%] MSWD=0.49 Group3 Mean,n=6 594.7 7.6 [1.3%] MSWD=0.30 Group1 Isoplot age unmix 605.5 5 (±2σ) [0.74%] Group2 Isoplot age unmix Gaussian Distribution (2σ)-assigned 1σ internal errors 636.3 11 (±2σ) [0.26%] relative misfit=0.930
367 Table 5 (continued): U-Pb absolute age data for zircon standards analysed by LA-ICPMS (Appendix a1). These standards have recognised age values (see Jackson et al., 2004 and Slama et al, 2008), which are used to tie the unknown zircon values by linear modelling (standards provide error bounds on unknown values). Block 1 (GJ standards 1-7), Block 2 (GJ standards 6-12) and Block 3 (GJ Standards 11-17) correspond to absolute age values 1-7, 8-16 and 17-26 respectively (see kw ages Table 5). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 206Pb/238U 207Pb/235U 208Pb/232Th 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ ±1σ ±1σ ±1σ ±1σ Conc. No. (Ma) (Ma) (Ma) (Ma) Kawr Suite (kw)-sample kw42, n=26 GJ GJ1 0.05973 0.00115 0.09790 0.00146 0.80614 0.01677 0.03025 0.00210 593.8 41.1 602.1 8.6 600.3 9.4 602.4 41.1 101 GJ2 0.06017 0.00075 0.09728 0.00143 0.80695 0.01290 0.03120 0.00101 609.6 26.8 598.4 8.4 600.7 7.3 620.9 19.8 98 GJ3 0.06039 0.00083 0.09860 0.00143 0.82101 0.01360 0.03041 0.00121 617.7 29.3 606.2 8.4 608.6 7.6 605.6 23.7 98 GJ4 0.05947 0.00130 0.09848 0.00152 0.80738 0.01866 0.03093 0.00245 584.3 46.8 605.5 8.9 601.0 10.5 615.6 48.1 104 GJ5 0.06072 0.00089 0.09908 0.00144 0.82947 0.01432 0.03150 0.00139 629.3 31.3 609.0 8.4 613.3 8.0 626.8 27.2 97 GJ6 0.06015 0.00086 0.09670 0.00151 0.80191 0.01438 0.02772 0.00116 608.9 30.8 595.1 8.9 597.9 8.1 552.6 22.8 98 GJ7 0.06002 0.00089 0.09807 0.00153 0.81153 0.01484 0.03403 0.00145 604.3 31.8 603.1 9.0 603.3 8.3 676.3 28.3 100 GJ8 0.05957 0.00081 0.09750 0.00145 0.80071 0.01345 0.03081 0.00118 587.8 29.1 599.8 8.5 597.2 7.6 613.3 23.1 102 GJ9 0.05992 0.00100 0.09726 0.00155 0.80344 0.01583 0.02865 0.00151 600.7 35.8 598.3 9.1 598.8 8.9 571.0 29.7 100 GJ10 0.05981 0.00103 0.09831 0.00157 0.81058 0.01627 0.03535 0.00191 596.6 37.0 604.5 9.2 602.8 9.1 702.2 37.4 101 GJ11 0.06011 0.00108 0.09745 0.00155 0.80760 0.01656 0.02994 0.00177 607.6 38.4 599.5 9.1 601.1 9.3 596.3 34.8 99 GJ12 0.06018 0.00117 0.09893 0.00158 0.82073 0.01771 0.03177 0.00211 610.0 41.5 608.1 9.3 608.5 9.9 632.2 41.3 100 GJ13 0.06032 0.00141 0.09768 0.00170 0.81231 0.02063 0.02953 0.00236 615.1 49.7 600.8 10.0 603.7 11.6 588.1 46.3 98 GJ14 0.06009 0.00124 0.09797 0.00160 0.81164 0.01842 0.03124 0.00235 606.8 44.0 602.5 9.4 603.4 10.3 621.7 46.0 99 GJ15 0.06001 0.00141 0.09790 0.00163 0.80996 0.02026 0.03069 0.00278 604.1 50.0 602.1 9.6 602.4 11.4 611.0 54.6 100 GJ16 0.06052 0.00132 0.09743 0.00149 0.81295 0.01867 0.03354 0.00264 622.2 46.4 599.3 8.8 604.1 10.5 666.7 51.7 96 GJ17 0.05940 0.00151 0.09803 0.00154 0.80277 0.02082 0.02969 0.00289 581.8 54.2 602.8 9.0 598.4 11.7 591.3 56.8 104 GJ Mean 606.0 17 [2σ] 602.2 4.2 [2σ] 602.8 4.3 [2σ] Weighted Av. 95% conf. (1.96σ) GJ Mean (GEMOC) 607.7 4.3 [2σ] 600.7 1.1[2σ] 602.0 1.0 [2σ] Plesovice ples1 0.05330 0.00068 0.05432 0.00081 0.39916 0.00655 0.01689 0.00042 341.3 28.7 341.0 5.0 341.0 4.8 338.5 8.4 100 ples2 0.05276 0.00067 0.05440 0.00081 0.39573 0.00644 0.01661 0.00041 318.6 28.4 341.5 5.0 338.5 4.7 333.0 8.1 107 ples3 0.05244 0.00089 0.05400 0.00086 0.39046 0.00777 0.01610 0.00080 304.8 38.2 339.0 5.3 334.7 5.7 322.9 15.9 111 ples4 0.05395 0.00092 0.05333 0.00085 0.39666 0.00790 0.01691 0.00086 368.8 38.2 334.9 5.2 339.2 5.7 339.0 17.1 91 ples5 0.05296 0.00075 0.05635 0.00078 0.41147 0.00677 0.01523 0.00050 327.2 31.9 353.4 4.7 349.9 4.9 305.4 10.0 108 ples6 0.05323 0.00127 0.05559 0.00085 0.40795 0.01004 0.01756 0.00151 338.5 53.2 348.8 5.2 347.4 7.2 351.9 30.0 103 Ples Mean 332.0 27 [2σ] 343.4 7.2 [2σ) 341.6 4.3 [2σ] Weighted Av. 95% conf. (1.96σ) Ples Mean (Slama et al., 2008) 339.2 0.25 [2σ] 337.1 0.37 [2σ] 337.3 0.11 [2σ]
368 Table 6: U-Pb isotope data from Al Hafoor Suite (ao) zircon grains analysed by LA-ICPMS (Appendix a1). These values have been numerically arranged to highlight the maximum and minimum values. Consequently, the spot numbers are no longer in subsequent experimental time. However, spot numbers 1-7 and 8-16 correspond to Block 1 (GJ standards 1-7) and Block 2 (GJ standards 6-12) respectively (see standard Table 6-continued). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ 207Pb/206Pb ±1σ 206Pb/238U ±1σ 207Pb/235U ±1σ 208Pb/232Th ±1σ Conc. σ from No. (Ma) (Ma) (Ma) (Ma) mean Al Hafoor Suite (ao)-sample ao85, n=16 Spot15 0.06486 0.00094 0.10617 0.00153 0.95065 0.01607 0.03879 0.00081 769.8 30.1 650.5 8.9 678.4 8.4 769.1 15.8 85 1.62 Spot13 0.06287 0.00166 0.10596 0.00173 0.91557 0.02447 0.03798 0.00239 703.8 55.3 649.2 10.1 660.0 13.0 753.5 46.6 92 1.30 Spot8 0.06048 0.00071 0.10560 0.00138 0.88038 0.01239 0.03579 0.00048 620.8 25.0 647.2 8.1 641.2 6.7 710.8 9.3 104 1.39 Spot16 0.06601 0.00103 0.10469 0.00152 0.95408 0.01695 0.04021 0.00089 806.8 32.2 641.8 8.9 680.2 8.8 796.8 17.3 80 0.65 Spot11 0.06382 0.00080 0.10467 0.00138 0.92102 0.01352 0.04264 0.00068 735.6 26.3 641.7 8.1 662.9 7.2 844.0 13.2 87 0.70 Spot10 0.06393 0.00073 0.10388 0.00134 0.91564 0.01257 0.03854 0.00050 739.2 24.0 637.1 7.8 660.1 6.7 764.3 9.8 86 0.14 Spot2 0.06056 0.00071 0.10380 0.00134 0.86660 0.01203 0.03591 0.00048 623.6 25.0 636.6 7.8 633.7 6.6 713.1 9.3 102 0.07 Spot9 0.06378 0.00076 0.10344 0.00134 0.90968 0.01272 0.03837 0.00053 734.3 24.9 634.5 7.8 656.9 6.8 761.0 10.3 86 -0.20 Spot4 0.06441 0.00074 0.10330 0.00133 0.91726 0.01261 0.03748 0.00046 755.1 24.1 633.7 7.8 660.9 6.7 743.6 9.0 84 -0.30 Spot5 0.06395 0.00081 0.10330 0.00134 0.91072 0.01337 0.04083 0.00063 740.0 26.7 633.7 7.8 657.4 7.1 808.8 12.3 86 -0.30 Spot3 0.06431 0.00077 0.10320 0.00133 0.91491 0.01286 0.03734 0.00049 751.8 25.0 633.1 7.8 659.7 6.8 741.1 9.6 84 -0.38 Spot14 0.06491 0.00075 0.10313 0.00145 0.92384 0.01362 0.03403 0.00054 771.3 24.1 632.7 8.4 664.4 7.2 676.5 10.6 82 -0.40 Spot12 0.06158 0.00073 0.10311 0.00133 0.87549 0.01223 0.04017 0.00063 659.4 25.4 632.6 7.8 638.5 6.6 796.0 12.2 96 -0.44 Spot6 0.06288 0.00076 0.10304 0.00133 0.89322 0.01268 0.03760 0.00053 704.1 25.5 632.2 7.8 648.1 6.8 746.0 10.3 90 -0.49 Spot1 0.06571 0.00082 0.10248 0.00133 0.92835 0.01344 0.03947 0.00054 797.1 26.0 628.9 7.8 666.8 7.1 782.5 10.5 79 -0.92 Spot7 0.06568 0.00081 0.10137 0.00131 0.91801 0.01310 0.03945 0.00054 796.3 25.6 622.4 7.6 661.3 6.9 782.1 10.5 78 -1.78
ao Mean, n=16 U-Pb Concordia (isoptope ratios): Groups seperated based on σ from mean 639.6 7.9 (±1σ) MSWD=0.79
Weighted Av. (assigned internal errors) 95% conf. 1.96σ: Groups seperated based on σ ao Mean, n=16 636.0 4 [0.63%] MSWD=0.81 from mean
369 Table 6 (continued): U-Pb absolute age data for zircon standards analysed by LA-ICPMS (Appendix a1). These standards have recognised age values (see Jackson et al., 2004 and Slama et al, 2008), which are used to tie the unknown zircon values by linear modelling (standards provide error bounds on unknown values). Block 1 (GJ standards 1-7) and Block 2 (GJ standards 6-12) correspond to absolute age values 1-7 and 8-16 respectively (see ao ages Table 6). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 206Pb/238U 207Pb/235U 208Pb/232Th 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ ±1σ ±1σ ±1σ ±1σ Conc. No. (Ma) (Ma) (Ma) (Ma) Al Hafoor Suite (ao)-sample ao85, n=16 GJ GJ1 0.05926 0.00102 0.09800 0.00133 0.80062 0.01475 0.02888 0.00186 576.5 37.1 602.7 7.8 597.2 8.3 575.5 36.5 105 GJ2 0.05961 0.00103 0.09695 0.00131 0.79671 0.01466 0.03273 0.00194 589.3 37.0 596.5 7.7 595.0 8.3 651.0 38.0 101 GJ3 0.05988 0.00102 0.09784 0.00132 0.80769 0.01474 0.03207 0.00227 599.1 36.6 601.8 7.8 601.2 8.3 638.0 44.5 100 GJ4 0.06129 0.00108 0.09761 0.00133 0.82480 0.01543 0.03290 0.00241 649.5 37.4 600.4 7.8 610.7 8.6 654.4 47.1 92 GJ5 0.05993 0.00110 0.09800 0.00135 0.80969 0.01565 0.02936 0.00250 601.0 39.3 602.7 7.9 602.3 8.8 585.0 49.1 100 GJ6 0.05968 0.00108 0.09776 0.00134 0.80439 0.01535 0.03555 0.00230 592.7 38.1 601.3 7.9 599.3 8.6 706.0 45.0 101 GJ7 0.06015 0.00107 0.09725 0.00133 0.80652 0.01519 0.02764 0.00195 609.1 38.0 598.3 7.8 600.5 8.5 551.0 38.4 98 GJ8 0.05921 0.00105 0.09774 0.00134 0.79784 0.01509 0.03256 0.00242 574.8 38.2 601.1 7.9 595.6 8.5 647.6 47.3 105 GJ9 0.05954 0.00103 0.09771 0.00134 0.80204 0.01489 0.03281 0.00216 587.1 37.1 601.0 7.9 598.0 8.4 652.5 42.3 102 GJ10 0.06053 0.00104 0.09811 0.00134 0.81869 0.01513 0.03144 0.00221 622.7 36.8 603.3 7.9 607.3 8.5 625.7 43.4 97 GJ11 0.05962 0.00108 0.09828 0.00136 0.80756 0.01562 0.03077 0.00206 589.9 38.8 604.3 8.0 601.1 8.8 612.5 40.3 102 GJ12 0.06027 0.00114 0.09720 0.00135 0.80760 0.01611 0.03026 0.00208 613.1 40.3 598.0 8.0 601.1 9.1 602.6 40.7 98 GJ Mean 600.0 21 [2σ] 600.9 4.4 [2σ] 600.7 4.8 [2σ] Weighted Av. 95% conf. (1.96σ) GJ Mean (GEMOC) 607.7 4.3 [2σ] 600.7 1.1[2σ] 602.0 1.0 [2σ] Plesovice ples1 0.05441 0.00084 0.05478 0.00073 0.41094 0.00696 0.02055 0.00054 388.0 34.3 343.8 4.4 349.5 5.0 411.1 10.8 89 ples2 0.05306 0.00077 0.05375 0.0007 0.3932 0.00634 0.02076 0.00044 331.4 32.5 337.5 4.3 336.7 4.6 415.3 8.6 102 ples3 0.0527 0.00098 0.05337 0.00071 0.38773 0.0075 0.01966 0.00079 315.8 41.6 335.2 4.4 332.7 5.5 393.6 15.6 106 ples4 0.05309 0.00087 0.05342 0.00072 0.39097 0.00695 0.0186 0.00061 332.5 36.7 335.5 4.4 335.1 5.1 372.5 12.1 101 Ples Mean 344.0 35 [2σ] 338.0 4.3 [2σ) 339.0 12 [2σ] Weighted Av. 95% conf. (1.96σ) Ples Mean (Slama et al., 2008) 339.2 0.25 [2σ] 337.1 0.37 [2σ] 337.3 0.11 [2σ]
370 Table 7: U-Pb isotope data from Najirah Granite (nr) zircon grains analysed by LA-ICPMS (Appendix a1). The isotope data has been subdivided into 3 groups based on their zircon morphology and 1σ error from the total mean of the suite, n=20 (Chapter 6). These values have been numerically arranged to highlight the maximum and minimum values. Consequently, the spot numbers are no longer in subsequent experimental time. However, spot numbers 1-5, 6- 13 and 14-20 correspond to Block 1 (GJ standards 1-7), Block 2 (GJ standards 6-12) and Block 3 (GJ standards 11-17) respectively (see standard Table 7- continued). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 206Pb/238U 207Pb/235U 208Pb/232Th σ from 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ ±1σ ±1σ ±1σ ±1σ Conc. No. (Ma) (Ma) (Ma) (Ma) mean Najirah Granite (nr)-sample nr120, n=20 Group1 Spot18 0.06011 0.00231 0.10403 0.00199 0.86218 0.03275 0.03560 0.00524 607.6 81.1 638.0 11.6 631.3 17.9 707.1 102.3 105 2.66 Spot20 0.06246 0.00261 0.10348 0.00206 0.89109 0.03646 0.04338 0.00720 689.9 86.6 634.7 12.0 647.0 19.6 858.3 139.4 92 2.30 Spot3 0.06087 0.00102 0.10300 0.00153 0.86449 0.01640 0.03024 0.00148 634.8 35.6 632.0 9.0 632.6 8.9 602.1 29.0 100 2.79 Spot5 0.06198 0.00097 0.10276 0.00154 0.87819 0.01608 0.03337 0.00148 673.5 33.0 630.6 9.0 640.0 8.7 663.6 28.9 94 2.62 Spot15 0.06365 0.00264 0.10121 0.00202 0.88817 0.03619 0.03416 0.00527 730.0 85.6 621.5 11.8 645.4 19.5 678.9 103.1 85 1.22 Group2 Spot10 0.06045 0.00126 0.10006 0.00159 0.83396 0.01882 0.03046 0.00218 619.7 44.3 614.8 9.3 615.8 10.4 606.5 42.8 99 0.84 Spot11 0.06207 0.00131 0.09977 0.00159 0.85380 0.01945 0.03380 0.00246 676.5 44.4 613.0 9.3 626.7 10.7 671.9 48.2 91 0.64 Spot17 0.06328 0.00227 0.09965 0.00185 0.86947 0.03096 0.03637 0.00500 717.8 74.5 612.4 10.8 635.3 16.8 722.0 97.6 85 0.50 Spot9 0.06036 0.00119 0.09864 0.00155 0.82090 0.01774 0.03128 0.00213 616.4 41.9 606.4 9.1 608.5 9.9 622.6 41.8 98 -0.07 Spot8 0.06063 0.00126 0.09841 0.00156 0.82264 0.01849 0.03023 0.00207 626.0 44.1 605.1 9.1 609.5 10.3 602.0 40.6 97 -0.21 Spot2 0.05948 0.00090 0.09810 0.00146 0.80445 0.01443 0.02759 0.00107 584.6 32.7 603.3 8.6 599.3 8.1 550.1 21.0 103 -0.44 Spot7 0.06190 0.00132 0.09798 0.00155 0.83621 0.01919 0.03101 0.00213 670.8 45.0 602.5 9.1 617.1 10.6 617.3 41.8 90 -0.50 Spot13 0.06553 0.00147 0.09794 0.00157 0.88495 0.02118 0.03554 0.00284 791.5 46.5 602.4 9.2 643.7 11.4 706.0 55.4 76 -0.50 Spot4 0.06159 0.00109 0.09781 0.00149 0.83065 0.01656 0.02933 0.00124 660.0 37.5 601.6 8.8 614.0 9.2 584.3 24.3 91 -0.62 Group3 Spot14 0.06571 0.00207 0.09618 0.00170 0.87127 0.02760 0.03777 0.00448 797.1 64.6 592.0 10.0 636.3 15.0 749.4 87.4 74 -1.50 Spot16 0.06932 0.00361 0.09528 0.00224 0.91049 0.04632 0.03098 0.00591 908.3 103.9 586.7 13.2 657.3 24.6 616.7 115.9 65 -1.54 Spot12 0.06081 0.00119 0.09495 0.00150 0.79613 0.01722 0.02882 0.00196 632.6 41.5 584.8 8.8 594.6 9.7 574.2 38.5 92 -2.51 Spot1 0.06214 0.00238 0.09476 0.00194 0.81172 0.03112 0.02171 0.00162 679.1 79.8 583.6 11.4 603.4 17.4 434.2 32.1 86 -2.05 Spot19 0.06444 0.00409 0.09463 0.00249 0.84072 0.05160 0.02681 0.00623 756.0 128.5 582.9 14.7 619.5 28.5 534.8 122.6 77 -1.65 Spot6 0.06162 0.00220 0.09422 0.00184 0.80041 0.02853 0.02346 0.00299 660.8 74.6 580.4 10.8 597.1 16.1 468.6 59.0 88 -2.46
nr Mean, n=20 616.0 9.5 (±1σ) MSWD=2.1 Group1 Mean,n=5 634.0 12 (±1σ) MSWD=0.087 U-Pb Concordia (isoptope ratios): Groups seperated based on σ from mean Group2 Mean,n=9 607.1 7.9 (±1σ) MSWD=0.34 Group3 Mean,n=6 582.0 16 (±1σ) MSWD=0.13
nr Mean, n=20 607.0 7.9 [1.3%] MSWD=2.9 Group1 Mean,n=5 Weighted Av. (assigned internal errors) 95% conf. 1.96σ: Groups seperated based 631.4 9.1 [1.4%] MSWD=0.28 Group2 Mean,n=9 on σ from mean 606.5 6 [0.99%] MSWD=0.31 Group3 Mean,n=6 585.4 8.8 [1.5%] MSWD=0.28
Group1 Isoplot age unmix 599.6 5.8 (±2σ) [0.74%] Group2 Isoplot age unmix Gaussian Distribution (2σ)-assigned 1σ internal errors 629 12 (±2σ) [0.26%] relative misfit=0.916
371 Table 7 (continued): U-Pb absolute age data for zircon standards analysed by LA-ICPMS (Appendix a1). These standards have recognised age values (see Jackson et al., 2004 and Slama et al, 2008), which are used to tie the unknown zircon values by linear modelling (standards provide error bounds on unknown values). Block 1 (GJ standards 1-7), Block 2 (GJ standards 6-12) and Block 3 (GJ standards 11-17) correspond to absolute age values 1-5, 6-13 and 14-20 respectively (see nr ages Table 7). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 206Pb/238U 207Pb/235U 208Pb/232Th 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ ±1σ ±1σ ±1σ ±1σ Conc. No. (Ma) (Ma) (Ma) (Ma) Najirah Granite (nr)-sample nr120, n=20 GJ GJ1 0.06022 0.00083 0.09910 0.00146 0.82285 0.01389 0.03255 0.00122 611.5 29.6 609.2 8.5 609.6 7.7 647.4 23.9 100 GJ2 0.06027 0.00086 0.09737 0.00144 0.80920 0.01399 0.03339 0.00130 613.4 30.5 599.0 8.5 602.0 7.9 663.8 25.3 98 GJ3 0.06013 0.00084 0.09836 0.00145 0.81539 0.01384 0.02936 0.00114 608.2 29.8 604.8 8.5 605.5 7.7 584.9 22.4 99 GJ4 0.06010 0.00082 0.09645 0.00142 0.79911 0.01342 0.02844 0.00107 607.0 29.2 593.5 8.4 596.3 7.6 566.9 21.0 98 GJ5 0.06065 0.00112 0.09742 0.00152 0.81468 0.01679 0.03195 0.00193 626.8 39.3 599.3 8.9 605.1 9.4 635.6 37.8 96 GJ6 0.06007 0.00118 0.09693 0.00153 0.80284 0.01733 0.03029 0.00202 606.3 41.8 596.4 9.0 598.4 9.8 603.2 39.6 98 GJ7 0.05975 0.00108 0.09685 0.00151 0.79796 0.01629 0.03005 0.00176 594.4 38.9 595.9 8.9 595.7 9.2 598.4 34.6 100 GJ8 0.06018 0.00113 0.09864 0.00154 0.81847 0.01710 0.03033 0.00189 610.1 40.0 606.4 9.1 607.2 9.6 603.9 37.1 99 GJ9 0.06053 0.00119 0.09889 0.00155 0.82534 0.01779 0.03113 0.00209 622.6 41.8 607.9 9.1 611.0 9.9 619.6 40.9 98 GJ10 0.06005 0.00172 0.09675 0.00166 0.80095 0.02344 0.03032 0.00322 605.3 60.9 595.4 9.8 597.4 13.2 603.7 63.2 98 GJ11 0.06045 0.00178 0.09751 0.00168 0.81258 0.02431 0.03042 0.00334 619.7 62.4 599.8 9.9 603.9 13.6 605.6 65.5 97 GJ12 0.06040 0.00191 0.09742 0.00172 0.81117 0.02581 0.03145 0.00374 617.9 66.9 599.3 10.1 603.1 14.5 625.9 73.4 97 GJ13 0.05966 0.00186 0.09874 0.00174 0.81207 0.02558 0.02994 0.00352 591.2 66.4 607.0 10.2 603.6 14.3 596.3 69.0 103 GJ14 0.06000 0.00195 0.09846 0.00176 0.81442 0.02656 0.03096 0.00382 603.6 68.9 605.3 10.3 604.9 14.9 616.4 74.9 100 GJ15 0.06043 0.00194 0.09770 0.00177 0.81387 0.02640 0.03178 0.00391 618.8 67.7 600.9 10.4 604.6 14.8 632.4 76.6 97 GJ16 0.05993 0.00214 0.09712 0.00182 0.80241 0.02857 0.02911 0.00413 600.9 75.6 597.5 10.7 598.2 16.1 579.9 81.2 99 GJ17 0.06011 0.00093 0.09798 0.00128 0.81196 0.01363 0.03025 0.00150 609.9 49.4 601.1 9.4 602.9 11.3 611.5 49.2 99 GJ Mean 610.0 20 [2σ] 601.1 4.4 [2σ] 603.1 4.8 [2σ] Weighted Av. 95% conf. (1.96σ) GJ Mean (GEMOC) 607.7 4.3 [2σ] 600.7 1.1[2σ] 602.0 1.0 [2σ] Plesovice ples1 0.05311 0.00066 0.05465 0.00080 0.40020 0.00639 0.01470 0.00035 333.3 27.9 343.0 4.9 341.8 4.6 294.9 6.9 103 ples2 0.05313 0.00067 0.05555 0.00081 0.40694 0.00653 0.01440 0.00035 334.4 28.1 348.5 5.0 346.7 4.7 289.0 6.9 104 ples3 0.05393 0.00098 0.05616 0.00087 0.41762 0.00850 0.01634 0.00092 368.0 40.5 352.2 5.3 354.3 6.1 327.6 18.2 96 ples4 0.05325 0.00105 0.05631 0.00087 0.41340 0.00889 0.01791 0.00112 339.3 43.8 353.1 5.3 351.3 6.4 358.7 22.2 104 ples5 0.05295 0.00152 0.05792 0.00100 0.42283 0.01236 0.01832 0.00189 326.6 63.8 363.0 6.1 358.1 8.8 367.0 37.6 111 ples6 0.05409 0.00170 0.05635 0.00100 0.42015 0.01331 0.01713 0.00196 374.4 69.0 353.4 6.1 356.2 9.5 343.2 39.0 94 Ples Mean 341.0 30 [2σ] 351.3 6.8 [2σ) 348.7 4.8 [2σ] Weighted Av. 95% conf. (1.96σ) Ples Mean (Slama et al., 2008) 339.2 0.25 [2σ] 337.1 0.37 [2σ] 337.3 0.11 [2σ]
372 Table 8: U-Pb isotope data from Wadbah Suite (wb) zircon grains analysed by LA-ICPMS (Appendix a1). The isotope data has been subdivided into 3 groups based on their zircon morphology and 1σ error from the total mean of the suite, n=26 (Chapter 6). These values have been numerically arranged to highlight the maximum and minimum values. Consequently, the spot numbers are no longer in subsequent experimental time. However, spot numbers 1-8, 9-18 and 19- 26 correspond to Block 1 (GJ standards 1-7), Block 2 (GJ standards 6-12) and Block 3 (GJ Standards 11-17) respectively (see standard Table 8-continued). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 206Pb/238U 207Pb/235U 208Pb/232Th σ from 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ ±1σ ±1σ ±1σ ±1σ Conc. No. (Ma) (Ma) (Ma) (Ma) mean Wadbah Suite (wb)-sample wb65, n=26 Group1 Spot6 0.05929 0.00152 0.10385 0.00162 0.84851 0.02199 0.03359 0.00182 577.6 54.8 636.9 9.5 623.8 12.1 667.8 35.7 110 2.23 Spot5 0.06031 0.00117 0.10341 0.00147 0.85989 0.01758 0.03548 0.00127 614.8 41.4 634.4 8.6 630.1 9.6 704.6 24.8 103 2.15 Spot19 0.06070 0.00091 0.10330 0.00133 0.86453 0.01403 0.03370 0.00098 628.6 31.9 633.7 7.8 632.6 7.6 669.9 19.1 101 2.29 Spot3 0.06123 0.00097 0.10303 0.00139 0.87019 0.01507 0.03418 0.00095 647.4 33.7 632.1 8.1 635.7 8.2 679.2 18.5 98 2.00 Spot1 0.06510 0.00158 0.10242 0.00156 0.91963 0.02263 0.03906 0.00159 777.5 50.2 628.5 9.1 662.2 12.0 774.4 31.0 81 1.39 Spot2 0.05898 0.00104 0.10206 0.00142 0.83019 0.01573 0.03367 0.00096 566.4 37.8 626.5 8.3 613.7 8.7 669.3 18.8 111 1.28 Spot20 0.06196 0.00103 0.10173 0.00134 0.86905 0.01534 0.03335 0.00104 672.7 35.3 624.6 7.8 635.1 8.3 663.0 20.4 93 1.12 Spot23 0.06072 0.00090 0.10169 0.00130 0.85136 0.01369 0.03408 0.00108 629.5 31.7 624.3 7.6 625.4 7.5 677.4 21.1 99 1.11 Group2 Spot14 0.05956 0.00144 0.10093 0.00148 0.82884 0.02027 0.03347 0.00239 587.8 51.8 619.9 8.7 613.0 11.3 665.4 46.8 105 0.47 Spot4 0.05998 0.00097 0.10084 0.00136 0.83423 0.01465 0.03393 0.00096 602.8 34.7 619.4 8.0 616.0 8.1 674.4 18.8 103 0.44 Spot11 0.06069 0.00175 0.10038 0.00156 0.83989 0.02393 0.03288 0.00299 628.2 60.9 616.6 9.1 619.1 13.2 653.9 58.6 98 0.08 Spot7 0.06164 0.00120 0.10020 0.00140 0.85144 0.01723 0.03450 0.00143 661.5 41.3 615.6 8.2 625.4 9.5 685.5 27.9 93 -0.03 Spot18 0.05888 0.00168 0.10009 0.00156 0.81249 0.02306 0.03367 0.00291 562.6 61.0 614.9 9.1 603.9 12.9 669.3 56.8 109 -0.11 Spot15 0.06280 0.00211 0.10004 0.00166 0.86619 0.02846 0.03730 0.00347 701.3 69.9 614.7 9.7 633.5 15.5 740.2 67.7 88 -0.12 Spot9 0.05897 0.00315 0.09974 0.00219 0.81067 0.04176 0.02986 0.00346 566.0 112.4 612.9 12.8 602.8 23.4 594.8 68.0 108 -0.23 Spot16 0.06238 0.00145 0.09956 0.00141 0.85628 0.02005 0.03518 0.00248 687.3 48.9 611.8 8.3 628.1 11.0 698.9 48.4 89 -0.49 Spot13 0.06205 0.00174 0.09943 0.00148 0.85049 0.02342 0.03364 0.00277 675.7 58.7 611.0 8.7 624.9 12.9 668.7 54.2 90 -0.56 Spot8 0.05999 0.00119 0.09916 0.00139 0.82007 0.01690 0.03462 0.00138 603.1 42.5 609.5 8.2 608.1 9.4 688.0 27.0 101 -0.78 Spot26 0.06069 0.00117 0.09893 0.00138 0.82788 0.01669 0.03327 0.00147 628.3 40.8 608.2 8.1 612.4 9.3 661.6 28.8 97 -0.95 Group3 Spot17 0.06079 0.00142 0.09878 0.00140 0.82790 0.01943 0.03362 0.00233 631.9 49.4 607.2 8.2 612.4 10.8 668.4 45.7 96 -1.05 Spot10 0.05897 0.00352 0.09870 0.00234 0.80208 0.04602 0.03122 0.00457 566.1 125.0 606.8 13.7 598.0 25.9 621.3 89.7 107 -0.66 Spot21 0.06252 0.00252 0.09851 0.00185 0.84872 0.03329 0.02844 0.00200 691.8 83.5 605.7 10.9 623.9 18.3 566.9 39.3 88 -0.94 Spot22 0.06190 0.00110 0.09794 0.00129 0.83576 0.01543 0.03282 0.00115 670.6 37.5 602.3 7.6 616.8 8.5 652.7 22.5 90 -1.79 Spot12 0.06408 0.00200 0.09776 0.00156 0.86371 0.02642 0.03612 0.00353 744.1 64.7 601.3 9.1 632.1 14.4 717.1 68.8 81 -1.59 Spot24 0.05983 0.00098 0.09723 0.00127 0.80206 0.01399 0.03286 0.00109 597.5 35.2 598.1 7.5 598.0 7.9 653.5 21.3 100 -2.38 Spot25 0.05973 0.00122 0.09644 0.00133 0.79423 0.01666 0.03240 0.00120 593.9 43.6 593.5 7.8 593.6 9.4 644.4 23.4 100 -2.86
wb Mean, n=26 617.9 5.4 (±1σ) MSWD=1.9 Group1 Mean,n=8 5.8 (±1σ) MSWD=0.35 U-Pb Concordia (isoptope ratios): Groups seperated based on σ from mean 630.0 Group2 Mean,n=11 614.6 5.6 (±1σ) MSWD=0.20 Group3 Mean,n=7 600.4 8 (±1σ) MSWD=0.39
wb Mean, n=26 615.9 4.9 [0.79%] MSWD=2.0 Group1 Mean,n=8 Weighted Av. (assigned internal errors) 95% conf. 1.96σ: Groups seperated based on σ from 629.8 5.7 [0.91%] MSWD=0.33 Group2 Mean,n=11 mean 614.0 5.2 [0.94%] MSWD=0.21 Group3 Mean,n=7 601.1 6.5 [1.1%] MSWD=0.34 Group1 Isoplot age unmix 607.5 6 (±2σ) [0.52%] Group2 Isoplot age unmix Gaussian Distribution (2σ)-assigned 1σ internal errors 624.7 6.5 (±2σ) [0.48%] relative misfit=0.957
373 Table 8 (continued): U-Pb absolute age data for zircon standards analysed by LA-ICPMS (Appendix a1). These standards have recognised age values (see Jackson et al., 2004 and Slama et al, 2008), which are used to tie the unknown zircon values by linear modelling (standards provide error bounds on unknown values). Block 1 (GJ standards 1-7), Block 2 (GJ standards 6-12) and Block 3 (GJ standards 11-17) correspond to absolute age values 1-8, 9-18 and 19-26 respectively (see wb ages Table 8). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 206Pb/238U 207Pb/235U 208Pb/232Th 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ ±1σ ±1σ ±1σ ±1σ Conc. No. (Ma) (Ma) (Ma) (Ma) Wadbah Suite (wb)-sample wb65, n=26 GJ GJ1 0.06005 0.00073 0.09751 0.00137 0.80721 0.01236 0.02956 0.00087 605.4 26.1 599.8 8.1 600.9 6.9 588.7 17.1 99 GJ2 0.06030 0.00074 0.09810 0.00137 0.81555 0.01246 0.03142 0.00094 614.4 26.3 603.3 8.0 605.6 7.0 625.3 18.5 98 GJ3 0.05999 0.00075 0.09878 0.00136 0.81700 0.01248 0.03019 0.00096 603.0 26.9 607.3 8.0 606.4 7.0 601.2 18.9 101 GJ4 0.05967 0.00076 0.09705 0.00132 0.79860 0.01215 0.03106 0.00101 591.5 27.3 597.1 7.7 596.0 6.9 618.1 19.7 101 GJ5 0.05987 0.00111 0.09716 0.00128 0.80194 0.01526 0.02967 0.00185 598.8 39.6 597.8 7.5 597.9 8.6 591.0 36.4 100 GJ6 0.05989 0.00110 0.09789 0.00129 0.80828 0.01535 0.03031 0.00188 599.7 39.4 602.0 7.6 601.5 8.6 603.5 37.0 100 GJ7 0.05999 0.00109 0.09849 0.00131 0.81461 0.01539 0.03237 0.00198 603.3 39.0 605.5 7.7 605.0 8.6 643.9 38.8 100 GJ8 0.06014 0.00111 0.09776 0.00130 0.81063 0.01550 0.03113 0.00194 608.7 39.5 601.3 7.7 602.8 8.7 619.7 38.1 99 GJ9 0.06002 0.00123 0.09775 0.00133 0.80890 0.01685 0.03086 0.00220 604.4 43.7 601.2 7.8 601.8 9.5 614.4 43.2 99 GJ10 0.06051 0.00131 0.09772 0.00137 0.81514 0.01797 0.03056 0.00237 621.7 46.0 601.0 8.0 605.3 10.1 608.5 46.4 97 GJ11 0.05976 0.00137 0.09767 0.00137 0.80468 0.01861 0.03112 0.00259 594.6 49.3 600.7 8.1 599.5 10.5 619.4 50.7 101 GJ12 0.05963 0.00080 0.09825 0.00125 0.80780 0.01209 0.03000 0.00116 590.2 28.9 604.2 7.3 601.2 6.8 597.4 22.7 102 GJ13 0.06008 0.00081 0.09774 0.00124 0.80970 0.01216 0.03098 0.00117 606.6 29.1 601.1 7.3 602.3 6.8 616.7 23.0 99 GJ14 0.06143 0.00080 0.09816 0.00125 0.83138 0.01224 0.03099 0.00112 654.3 27.8 603.6 7.3 614.4 6.8 616.9 22.0 92 GJ15 0.06013 0.00086 0.09807 0.00126 0.81306 0.01276 0.03224 0.00134 608.2 30.6 603.1 7.4 604.2 7.1 641.3 26.2 99 GJ16 0.06035 0.00092 0.09786 0.00127 0.81436 0.01345 0.03071 0.00147 616.3 32.6 601.9 7.5 604.9 7.5 611.4 28.9 98 GJ17 0.06011 0.00093 0.09798 0.00128 0.81196 0.01363 0.03025 0.00150 607.4 33.3 602.6 7.5 603.6 7.6 602.4 29.5 99 GJ Mean 608.0 15 [2σ] 602.0 3.6 [2σ] 603.4 3.7 [2σ] Weighted Av. 95% conf. (1.96σ) GJ Mean (GEMOC) 607.7 4.3 [2σ] 600.7 1.1[2σ] 602.0 1.0 [2σ] Plesovice ples1 0.05308 0.00064 0.05490 0.00076 0.40181 0.00605 0.01772 0.00037 332.3 27.0 344.6 4.7 343.0 4.4 355.1 7.4 104 ples2 0.05296 0.00094 0.05394 0.00071 0.39381 0.00730 0.01867 0.00103 326.8 39.9 338.7 4.3 337.2 5.3 373.9 20.5 104 ples3 0.05307 0.00094 0.05442 0.00072 0.39817 0.00736 0.01912 0.00104 331.9 39.6 341.6 4.4 340.3 5.4 382.9 20.7 103 ples4 0.05303 0.00068 0.05470 0.00069 0.39994 0.00581 0.01854 0.00046 329.9 28.9 343.3 4.2 341.6 4.2 371.4 9.1 104 ples5 0.05326 0.00068 0.05531 0.00070 0.40614 0.00587 0.02021 0.00050 339.7 28.5 347.0 4.3 346.1 4.2 404.5 10.0 102 ples6 0.05315 0.00068 0.05528 0.00073 0.40611 0.00580 0.02013 0.00052 332.1 32.8 343.0 4.4 341.6 4.7 377.6 13.5 100 Ples Mean 333.0 25 [2σ] 343.0 3.5 [2σ) 342.0 3.7 [2σ] Weighted Av. 95% conf. (1.96σ) Ples Mean (Slama et al., 2008) 339.2 0.25 [2σ] 337.1 0.37 [2σ] 337.3 0.11 [2σ]
374 Table 9: U-Pb isotope data from Ibn Hashbal Suite (ih) zircon grains analysed by LA-ICPMS (Appendix a1). These values have been numerically arranged to highlight the maximum and minimum values. Consequently, the spot numbers are no longer in subsequent experimental time. However, spot numbers 1-9 and 10-19 correspond to Block 1 (GJ standards 1-7) and Block 2 (GJ standards 6-12) respectively (see standard Table 9-continued). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ 207Pb/206Pb ±1σ 206Pb/238U ±1σ 207Pb/235U ±1σ 208Pb/232Th ±1σ Conc. σ from No. (Ma) (Ma) (Ma) (Ma) mean Ibn Hashbal Suite (ih)-sample ih68, n=19 Spot17 0.05945 0.00674 0.10544 0.00388 0.86409 0.09354 0.03414 0.01439 583.7 228.8 646.2 22.7 632.4 51.0 678.5 281.2 111 1.26 Spot2 0.06160 0.00225 0.10319 0.00165 0.87641 0.03093 0.03363 0.00592 660.2 76.3 633.1 9.7 639.0 16.7 668.6 115.8 96 1.61 Spot13 0.06139 0.00552 0.10307 0.00320 0.87239 0.07510 0.02961 0.01058 652.9 182.2 632.4 18.7 636.9 40.7 589.8 207.7 97 0.79 Spot4 0.06279 0.00222 0.10259 0.00158 0.88827 0.03026 0.03742 0.00690 701.3 73.5 629.6 9.2 645.4 16.3 742.6 134.4 90 1.30 Spot11 0.06101 0.00716 0.10197 0.00414 0.85731 0.09602 0.02766 0.01341 639.5 234.1 626.0 24.2 628.7 52.5 551.4 263.7 98 0.35 Spot6 0.06370 0.00175 0.10193 0.00135 0.89521 0.02383 0.03583 0.00529 731.5 57.1 625.7 7.9 649.2 12.8 711.6 103.2 86 1.02 Spot9 0.06000 0.00401 0.10149 0.00239 0.83968 0.05406 0.03189 0.00837 603.7 138.5 623.2 14.0 619.0 29.8 634.6 164.0 103 0.40 Spot3 0.06416 0.00304 0.10035 0.00189 0.88778 0.04042 0.04402 0.00832 747.0 96.9 616.5 11.1 645.2 21.7 870.6 161.1 83 -0.10 Spot1 0.05796 0.00212 0.10029 0.00144 0.80148 0.02844 0.03247 0.00422 528.0 78.4 616.1 8.4 597.7 16.0 645.8 82.5 117 -0.18 Spot7 0.06722 0.00251 0.10024 0.00162 0.92908 0.03354 0.03918 0.00725 844.6 75.7 615.8 9.5 667.1 17.7 776.8 140.9 73 -0.19 Spot14 0.05915 0.00303 0.10011 0.00186 0.81647 0.04031 0.02793 0.00604 572.6 107.6 615.1 10.9 606.1 22.5 556.8 118.8 107 -0.23 Spot18 0.06322 0.00704 0.09954 0.00366 0.86732 0.09172 0.03338 0.01516 715.6 220.3 611.7 21.4 634.1 49.9 663.7 296.6 85 -0.28 Spot8 0.06085 0.00176 0.09918 0.00135 0.83212 0.02333 0.03341 0.00528 634.0 61.1 609.6 7.9 614.8 12.9 664.3 103.4 96 -1.01 Spot5 0.06530 0.00231 0.09912 0.00154 0.89247 0.03050 0.03612 0.00625 784.1 72.6 609.2 9.0 647.7 16.4 717.1 121.8 78 -0.93 Spot10 0.06083 0.00410 0.09871 0.00234 0.82786 0.05377 0.03015 0.00760 633.1 139.0 606.8 13.8 612.4 29.9 600.4 149.0 96 -0.79 Spot15 0.06735 0.00458 0.09855 0.00242 0.91523 0.05962 0.02841 0.00791 848.7 135.4 605.9 14.2 659.8 31.6 566.3 155.5 71 -0.82 Spot12 0.06314 0.00546 0.09835 0.00299 0.85616 0.07075 0.03552 0.01341 713.1 173.8 604.7 17.6 628.0 38.7 705.5 261.7 85 -0.74 Spot19 0.06155 0.00534 0.09783 0.00298 0.83016 0.06870 0.03319 0.01336 658.5 175.8 601.7 17.5 613.7 38.1 659.9 261.5 91 -0.91 Spot16 0.06620 0.00624 0.09731 0.00320 0.88810 0.07976 0.03943 0.01730 812.7 185.6 598.6 18.8 645.3 42.9 781.7 336.5 74 -1.01
ih Mean, n=19 U-Pb Concordia (isoptope ratios): Groups seperated based on σ from mean 621.3 7.1 (±1σ) MSWD=0.68
Weighted Av. (assigned internal errors) 95% conf. 1.96σ: Groups seperated based on σ ih Mean, n=19 617.6 5.2 [0.84%] MSWD=0.76 from mean
375 Table 9 (continued): U-Pb absolute age data for zircon standards analysed by LA-ICPMS (Appendix a1). These standards have recognised age values (see Jackson et al., 2004 and Slama et al, 2008), which are used to tie the unknown zircon values by linear modelling (standards provide error bounds on unknown values). Block 1 (GJ standards 1-7) and Block 2 (GJ standards 6-12) correspond to absolute age values 1-9 and 10-19 respectively (see ih ages Table 9). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 206Pb/238U 207Pb/235U 208Pb/232Th 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ ±1σ ±1σ ±1σ ±1σ Conc. No. (Ma) (Ma) (Ma) (Ma) Ibn Hashbal Suite (ih)-sample ih68, n=19 GJ GJ1 0.05985 0.00071 0.09762 0.00109 0.80621 0.01000 0.02886 0.00082 598.1 25.4 600.4 6.4 600.3 5.6 575.1 16.1 100 GJ2 0.06039 0.00076 0.09901 0.00111 0.82504 0.01077 0.03554 0.00116 617.5 26.9 608.6 6.5 610.9 6.0 705.8 22.6 99 GJ3 0.05949 0.00146 0.09708 0.00121 0.79626 0.01888 0.03043 0.00382 585.1 52.2 597.3 7.1 594.7 10.7 605.8 75.0 102 GJ4 0.06048 0.00149 0.09782 0.00123 0.81563 0.01947 0.03129 0.00397 620.7 52.3 601.6 7.2 605.6 10.9 622.7 77.7 97 GJ5 0.06115 0.00153 0.09767 0.00124 0.82341 0.01998 0.03157 0.00392 644.4 53.0 600.8 7.3 609.9 11.1 628.2 76.9 93 GJ6 0.05972 0.00156 0.09775 0.00126 0.80477 0.02040 0.02842 0.00391 593.5 55.5 601.2 7.4 599.5 11.5 566.5 76.8 101 GJ7 0.05956 0.00233 0.09742 0.00156 0.79997 0.03041 0.02794 0.00572 587.6 82.7 599.2 9.2 596.8 17.2 556.9 112.5 102 GJ8 0.06067 0.00235 0.09847 0.00157 0.82372 0.03097 0.03027 0.00606 627.6 81.3 605.4 9.2 610.1 17.2 602.8 118.8 96 GJ9 0.06133 0.00245 0.09805 0.00159 0.82921 0.03218 0.03710 0.00737 651.0 83.7 603.0 9.4 613.2 17.9 736.3 143.7 93 GJ10 0.05962 0.00239 0.09813 0.00159 0.80667 0.03138 0.02929 0.00596 589.7 84.8 603.5 9.3 600.6 17.6 583.5 117.0 102 GJ11 0.06012 0.00275 0.09749 0.00170 0.80807 0.03550 0.03072 0.00691 607.8 96.1 599.7 10.0 601.4 19.9 611.5 135.5 99 GJ12 0.06040 0.00281 0.09799 0.00173 0.81604 0.03640 0.03136 0.00707 618.0 97.4 602.6 10.1 605.8 20.4 624.1 138.6 98 GJ Mean 609.0 27 [2σ] 602.0 4.5 [2σ] 604.3 5.9 [2σ] Weighted Av. 95% conf. (1.96σ) GJ Mean (GEMOC) 607.7 4.3 [2σ] 600.7 1.1[2σ] 602.0 1.0 [2σ] Plesovice ples1 0.05380 0.00073 0.05571 0.00062 0.41349 0.00575 0.01732 0.00045 362.4 30.4 349.5 3.8 351.4 4.1 347.1 9.0 96 ples2 0.05410 0.00145 0.05294 0.00068 0.39491 0.01025 0.01694 0.00198 375.3 59.1 332.5 4.2 337.9 7.5 339.5 39.3 89 ples3 0.05516 0.00146 0.05354 0.00069 0.40715 0.01046 0.01787 0.00209 418.5 57.6 336.2 4.2 346.8 7.6 358.1 41.6 80 ples4 0.05399 0.00215 0.05434 0.00087 0.40457 0.01560 0.01685 0.00328 370.6 86.9 341.1 5.3 345.0 11.3 337.8 65.1 92 Ples Mean 374.0 46 [2σ] 340.0 13 [2σ) 347.7 6.1 [2σ] Weighted Av. 95% conf. (1.96σ) Ples Mean (Slama et al., 2008) 339.2 0.25 [2σ] 337.1 0.37 [2σ] 337.3 0.11 [2σ]
376 Table 10: U-Pb isotope data from Ar Ruwaydah Suite (ku) zircon grains analysed by LA-ICPMS (Appendix a1). These values have been numerically arranged to highlight the maximum and minimum values. Consequently, the spot numbers are no longer in subsequent experimental time. However, spot numbers 1-10 and 11-20 correspond to Block 1 (GJ standards 1-7) and Block 2 (GJ standards 6-12) respectively (see standard Table 10-continued). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 1σ 206Pb/238U1σ 207Pb/235U 1σ 208Pb/232Th 1σ 207Pb/206Pb ±1σ 206Pb/238U ±1σ 207Pb/235U ±1σ 208Pb/232Th ±1σ Conc. σ from No. (Ma) (Ma) (Ma) (Ma) mean Ar Ruwaydah Suite (ku)-sample ku139, n=20 Spot11 0.05809 0.00306 0.10257 0.00262 0.82087 0.04248 0.01768 0.00263 532.7 111.7 629.4 15.3 608.5 23.7 354.2 52.3 118 1.13 Spot15 0.06018 0.00151 0.10256 0.00188 0.85105 0.02300 0.02606 0.00201 610.0 53.5 629.4 11.0 625.2 12.6 519.9 39.5 103 1.57 Spot18 0.06242 0.00179 0.10194 0.00180 0.87728 0.02568 0.04333 0.00460 688.4 60.0 625.8 10.6 639.5 13.9 857.3 89.2 91 1.30 Spot3 0.05951 0.00089 0.10184 0.00173 0.83539 0.01625 0.02620 0.00107 585.8 32.3 625.2 10.1 616.6 9.0 522.8 21.0 107 1.29 Spot5 0.06109 0.00127 0.10141 0.00186 0.85398 0.02039 0.02075 0.00105 642.3 44.0 622.6 10.9 626.8 11.2 415.2 20.8 97 0.97 Spot6 0.06254 0.00120 0.10107 0.00162 0.87144 0.01883 0.04403 0.00300 692.5 40.4 620.7 9.5 636.3 10.2 870.9 58.0 90 0.91 Spot17 0.06155 0.00184 0.10094 0.00198 0.85678 0.02648 0.02067 0.00166 658.6 62.9 619.9 11.6 628.4 14.5 413.5 32.9 94 0.67 Spot7 0.06335 0.00322 0.10085 0.00230 0.88039 0.04361 0.03803 0.00702 719.9 104.3 619.4 13.5 641.2 23.6 754.4 136.8 86 0.54 Spot19 0.06335 0.00322 0.10085 0.00230 0.88039 0.04361 0.03803 0.00702 719.9 104.3 619.4 13.5 641.2 23.6 754.4 136.8 86 0.54 Spot8 0.06448 0.00180 0.10005 0.00186 0.88942 0.02624 0.03774 0.00385 757.6 57.9 614.7 10.9 646.1 14.1 748.8 75.0 81 0.24 Spot20 0.06448 0.00180 0.10005 0.00186 0.88942 0.02624 0.03774 0.00385 757.6 57.9 614.7 10.9 646.1 14.1 748.8 75.0 81 0.24 Spot9 0.05784 0.00182 0.09981 0.00198 0.79600 0.02606 0.02381 0.00235 523.5 67.7 613.3 11.6 594.6 14.7 475.7 46.4 117 0.10 Spot14 0.05866 0.00142 0.09836 0.00174 0.79564 0.02060 0.02738 0.00199 554.6 52.0 604.8 10.2 594.4 11.7 546.0 39.1 109 -0.71 Spot4 0.06015 0.00135 0.09828 0.00186 0.81503 0.02044 0.02208 0.00126 609.0 47.6 604.3 10.9 605.3 11.4 441.4 25.0 99 -0.71 Spot10 0.05882 0.00234 0.09783 0.00216 0.79323 0.03177 0.01984 0.00241 560.6 84.3 601.7 12.7 593.0 18.0 397.2 47.7 107 -0.82 Spot2 0.05825 0.00098 0.09767 0.00163 0.78438 0.01596 0.02698 0.00100 538.6 37.1 600.8 9.6 588.0 9.1 538.1 19.6 112 -1.18 Spot12 0.05898 0.00186 0.09724 0.00195 0.79068 0.02610 0.02494 0.00264 566.2 67.2 598.2 11.5 591.6 14.8 497.9 52.1 106 -1.21 Spot16 0.06059 0.00208 0.09724 0.00202 0.81229 0.02789 0.02117 0.00185 624.7 72.5 598.2 11.8 603.7 15.6 423.3 36.6 96 -1.17 Spot13 0.06086 0.00168 0.09703 0.00184 0.81440 0.02346 0.02175 0.00158 634.1 58.2 597.0 10.8 604.9 13.1 435.0 31.3 94 -1.40 Spot1 0.06046 0.00104 0.09650 0.00169 0.80424 0.01684 0.02230 0.00081 620.2 36.6 593.9 9.9 599.2 9.5 445.8 15.9 96 -1.84
ku Mean, n=20 U-Pb Concordia (isoptope ratios): Groups seperated based on σ from mean 610.7 5.5 (±1σ) MSWD=1.03
Weighted Av. (assigned internal errors) 95% conf. 1.96σ: Groups seperated based on σ ku Mean, n=20 612.1 4.9 [0.80%] MSWD=1.12 from mean
377 Table 10 (continued): U-Pb absolute age data for zircon standards analysed by LA-ICPMS (Appendix a1). These standards have recognised age values (see Jackson et al., 2004 and Slama et al, 2008), which are used to tie the unknown zircon values by linear modelling (standards provide error bounds on unknown values). Block 1 (GJ standards 1-7) and Block 2 (GJ standards 6-12) correspond to absolute age values 1-10 and11-20 respectively (see ku ages Table 10). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 206Pb/238U 207Pb/235U 208Pb/232Th 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ ±1σ ±1σ ±1σ ±1σ Conc. No. (Ma) (Ma) (Ma) (Ma) Ar Ruwaydah Suite (ku)-sample ku139, n=20 GJ GJ1 0.06005 0.00094 0.09681 0.00151 0.80138 0.01497 0.03117 0.00156 605.3 33.4 595.7 8.9 597.6 8.4 620.5 30.6 98 GJ2 0.05961 0.00091 0.10009 0.00156 0.82244 0.01515 0.02956 0.00142 589.3 32.6 614.9 9.2 609.4 8.4 588.7 27.8 104 GJ3 0.06103 0.00096 0.09832 0.00155 0.82719 0.01558 0.02885 0.00146 640.4 33.4 604.5 9.1 612.1 8.7 574.9 28.8 94 GJ4 0.06036 0.00099 0.09569 0.00152 0.79619 0.01545 0.03257 0.00171 616.4 35.0 589.1 8.9 594.7 8.7 647.7 33.6 96 GJ5 0.05990 0.00103 0.09684 0.00153 0.79964 0.01590 0.03253 0.00184 600.1 36.7 595.9 9.0 596.6 9.0 647.0 36.1 99 GJ6 0.05994 0.00158 0.09784 0.00173 0.80851 0.02237 0.03049 0.00300 601.3 55.9 601.8 10.2 601.6 12.6 607.0 58.9 100 GJ7 0.06042 0.00165 0.09868 0.00176 0.82191 0.02348 0.03099 0.00321 618.5 58.0 606.7 10.3 609.1 13.1 616.9 62.8 98 GJ8 0.06146 0.00155 0.09710 0.00172 0.82269 0.02210 0.03139 0.00287 655.3 53.2 597.4 10.1 609.5 12.3 624.7 56.3 91 GJ9 0.05920 0.00165 0.09796 0.00176 0.79948 0.02326 0.02983 0.00317 574.5 59.4 602.4 10.4 596.5 13.1 594.2 62.2 105 GJ10 0.05968 0.00155 0.09728 0.00174 0.80038 0.02209 0.03074 0.00294 592.0 55.4 598.4 10.2 597.0 12.5 612.0 57.7 101 GJ11 0.06070 0.00196 0.09714 0.00186 0.81275 0.02706 0.03046 0.00400 628.4 68.0 597.6 10.9 604.0 15.2 606.5 78.5 95 GJ12 0.05985 0.00193 0.09815 0.00189 0.80975 0.02697 0.03085 0.00407 598.1 68.3 603.5 11.1 602.3 15.1 614.2 79.9 101 GJ Mean 610.0 25 [2σ] 600.5 5.5 [2σ] 602.5 6.0 [2σ] Weighted Av. 95% conf. (1.96σ) GJ Mean (GEMOC) 607.7 4.3 [2σ] 600.7 1.1[2σ] 602.0 1.0 [2σ] Plesovice ples1 0.05271 0.00076 0.05449 0.00085 0.39595 0.00711 0.01644 0.00050 316.3 32.5 342.0 5.2 338.7 5.2 329.6 9.9 108 ples2 0.05284 0.00081 0.05409 0.00085 0.39400 0.00735 0.01624 0.00057 321.9 34.5 339.6 5.2 337.3 5.4 325.6 11.3 105 ples3 0.05355 0.00122 0.05441 0.00095 0.40168 0.01002 0.01549 0.00114 351.9 50.8 341.5 5.8 342.9 7.3 310.8 22.7 97 ples4 0.05290 0.00098 0.05443 0.00092 0.39694 0.00857 0.01509 0.00081 324.5 41.5 341.7 5.6 339.4 6.2 302.7 16.1 105 Ples Mean 325.0 37 [2σ] 341.2 5.3 [2σ) 339.1 5.7 [2σ] Weighted Av. 95% conf. (1.96σ) Ples Mean (Slama et al., 2008) 339.2 0.25 [2σ] 337.1 0.37 [2σ] 337.3 0.11 [2σ]
378 Table 11: U-Pb isotope data from Haml Suite (hla) zircon grains analysed by LA-ICPMS(Appendix a1). These values have been numerically arranged to highlight the maximum and minimum values. Consequently, the spot numbers are no longer in subsequent experimental time. However, spot numbers 1-7 and 8-15 correspond to Block 1 (GJ standards 1-7) and Block 2 (GJ standards 6-12) respectively (see standard Table 11-continued). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 1σ 206Pb/238U1σ 207Pb/235U 1σ 208Pb/232Th 1σ 207Pb/206Pb ±1σ 206Pb/238U ±1σ 207Pb/235U ±1σ 208Pb/232Th ±1σ Conc. σ from No. (Ma) (Ma) (Ma) (Ma) mean Haml Suite (hla)-sample hla110, n=15 Spot9 0.06070 0.00143 0.10227 0.00160 0.85593 0.02085 0.03205 0.00258 628.6 49.9 627.7 9.4 627.9 11.4 637.7 50.6 100 2.04 Spot1 0.06111 0.00077 0.10218 0.00148 0.86085 0.01365 0.02972 0.00059 643.1 27.0 627.2 8.7 630.6 7.5 591.9 11.7 98 2.14 Spot12 0.06178 0.00139 0.10187 0.00161 0.86768 0.02051 0.03021 0.00224 666.6 47.3 625.3 9.4 634.3 11.2 601.5 44.0 94 1.78 Spot2 0.06359 0.00164 0.10128 0.00160 0.88759 0.02314 0.03330 0.00149 727.9 53.7 621.9 9.4 645.1 12.5 662.1 29.2 85 1.42 Spot3 0.06039 0.00080 0.09978 0.00146 0.83078 0.01360 0.02866 0.00062 617.7 28.4 613.1 8.6 614.0 7.5 571.2 12.1 99 0.52 Spot11 0.06377 0.00147 0.09978 0.00158 0.87724 0.02113 0.03184 0.00246 734.0 48.0 613.1 9.2 639.5 11.4 633.4 48.2 84 0.49 Spot13 0.06215 0.00245 0.09971 0.00201 0.85439 0.03351 0.02937 0.00409 679.2 82.2 612.7 11.8 627.1 18.4 585.1 80.3 90 0.35 Spot7 0.06595 0.00284 0.09832 0.00207 0.89413 0.03771 0.03826 0.00473 804.7 87.7 604.6 12.1 648.6 20.2 758.9 92.1 75 -0.33 Spot5 0.06050 0.00092 0.09810 0.00146 0.81825 0.01466 0.03016 0.00095 621.5 32.6 603.3 8.6 607.1 8.2 600.6 18.5 97 -0.62 Spot4 0.06250 0.00123 0.09792 0.00164 0.84378 0.01868 0.02635 0.00118 691.3 41.5 602.2 9.6 621.2 10.3 525.7 23.2 87 -0.67 Spot10 0.06168 0.00178 0.09774 0.00171 0.83119 0.02446 0.02863 0.00294 663.2 60.5 601.1 10.0 614.3 13.6 570.5 57.8 91 -0.75 Spot15 0.06361 0.00321 0.09766 0.00214 0.85660 0.04185 0.03203 0.00589 728.8 103.5 600.7 12.6 628.3 22.9 637.3 115.5 82 -0.63 Spot14 0.06451 0.00295 0.09705 0.00205 0.86301 0.03862 0.03152 0.00520 758.3 93.7 597.1 12.0 631.8 21.1 627.3 101.8 79 -0.96 Spot6 0.06149 0.00107 0.09575 0.00154 0.81166 0.01642 0.02985 0.00125 656.4 37.0 589.4 9.1 603.4 9.2 594.4 24.5 90 -2.12 Spot8 0.06626 0.00117 0.09420 0.00155 0.86050 0.01763 0.02902 0.00149 814.7 36.5 580.3 9.1 630.4 9.6 578.2 29.2 71 -3.11
hla Mean, n=15 U-Pb Concordia (isoptope ratios): Groups seperated based on σ from mean 619.3 7.3 (±1σ) MSWD=1.4
Weighted Av. (assigned internal errors) 95% conf. 1.96σ: Groups seperated based on σ hla Mean, n=15 608.6 8.1 [1.3%] MSWD=2.3 from mean
379 Table 11 (continued): U-Pb absolute age data for zircon standards analysed by LA-ICPMS (Appendix a1). These standards have recognised age values (see Jackson et al., 2004 and Slama et al, 2008), which are used to tie the unknown zircon values by linear modelling (standards provide error bounds on unknown values). Block 1 (GJ standards 1-7) and Block 2 (GJ standards 6-12) correspond to absolute age values 1-7 and 8-15 respectively (see hla ages Table 11). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 206Pb/238U 207Pb/235U 208Pb/232Th 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ ±1σ ±1σ ±1σ ±1σ Conc. No. (Ma) (Ma) (Ma) (Ma) Haml Suite (hla)-sample hla110, n=15 GJ GJ1 0.06046 0.00074 0.09748 0.00138 0.81252 0.01241 0.03090 0.00096 620.2 26.2 599.6 8.1 603.9 7.0 615.1 18.8 97 GJ2 0.05960 0.00071 0.09790 0.00141 0.80441 0.01233 0.02873 0.00086 589.2 25.8 602.1 8.3 599.3 6.9 572.6 16.9 102 GJ3 0.06072 0.00076 0.09744 0.00138 0.81567 0.01263 0.03021 0.00100 629.3 26.7 599.4 8.1 605.6 7.1 601.5 19.5 95 GJ4 0.06003 0.00098 0.09794 0.00148 0.81053 0.01521 0.03127 0.00166 604.5 35.1 602.3 8.7 602.7 8.5 622.3 32.5 100 GJ5 0.06018 0.00104 0.09770 0.00148 0.81065 0.01580 0.03134 0.00182 610.1 37.1 600.9 8.7 602.8 8.9 623.8 35.7 98 GJ6 0.06057 0.00115 0.09727 0.00148 0.81232 0.01676 0.02986 0.00197 624.0 40.4 598.4 8.7 603.8 9.4 594.8 38.6 96 GJ7 0.05997 0.00105 0.09826 0.00150 0.81231 0.01593 0.03102 0.00181 602.4 37.3 604.2 8.8 603.7 8.9 617.5 35.4 100 GJ8 0.06057 0.00137 0.09758 0.00156 0.81489 0.01944 0.03108 0.00252 624.2 48.0 600.2 9.2 605.2 10.9 618.6 49.5 96 GJ9 0.06003 0.00135 0.09757 0.00156 0.80756 0.01922 0.03124 0.00253 604.8 47.9 600.2 9.2 601.1 10.8 621.7 49.7 99 GJ10 0.05954 0.00166 0.09817 0.00164 0.80582 0.02274 0.02966 0.00307 586.9 59.2 603.7 9.6 600.1 12.8 590.8 60.2 103 GJ11 0.06044 0.00159 0.09773 0.00164 0.81439 0.02212 0.03142 0.00309 619.4 55.7 601.1 9.6 604.9 12.4 625.3 60.6 97 GJ12 0.05999 0.00158 0.09726 0.00163 0.80443 0.02185 0.03047 0.00299 603.3 55.8 598.3 9.6 599.3 12.3 606.7 58.6 99 GJ Mean 611.0 21 [2σ] 600.8 5.0 [2σ] 602.8 5.1 [2σ] Weighted Av. 95% conf. (1.96σ) GJ Mean (GEMOC) 607.7 4.3 [2σ] 600.7 1.1[2σ] 602.0 1.0 [2σ] Plesovice ples1 0.05279 0.00064 0.05215 0.00074 0.37953 0.00578 0.01645 0.00037 319.9 27.3 327.7 4.5 326.7 4.3 329.8 7.4 102 ples2 0.05362 0.00095 0.05192 0.00079 0.38384 0.0076 0.017 0.00096 355.1 39.8 326.3 4.8 329.9 5.6 340.7 19.0 92 ples3 0.0531 0.00119 0.05268 0.00084 0.38563 0.00915 0.01711 0.00134 332.9 49.9 330.9 5.2 331.2 6.7 342.9 26.6 99 ples4 0.05385 0.00124 0.05276 0.00085 0.39165 0.0095 0.01696 0.00136 364.5 51.0 331.4 5.2 335.6 6.9 339.9 27.1 91 Ples Mean 336.0 37 [2σ] 328.9 4.8 [2σ) 329.7 5.4 [2σ] Weighted Av. 95% conf. (1.96σ) Ples Mean (Slama et al., 2008) 339.2 0.25 [2σ] 337.1 0.37 [2σ] 337.3 0.11 [2σ]
380 Table 12: U-Pb isotope data from Kawr Suite (kw) zircon grains analysed by LA-ICPMS (Appendix a1). These values have been numerically arranged to highlight the maximum and minimum values. Consequently, the spot numbers are no longer in subsequent experimental time. However, spot numbers 1-11 correspond to Block 1 (GJ standards 1-7) respectively. Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ 207Pb/206Pb ±1σ 206Pb/238U ±1σ 207Pb/235U ±1σ 208Pb/232Th ±1σ Conc. σ from No. (Ma) (Ma) (Ma) (Ma) mean Kawr Suite (kw)-sample kw51p, n=11 Spot8 0.05968 0.0006 0.105 0.00166 0.8638 0.01348 0.03061 0.00038 592.7 21.12 643.7 9.66 632.2 7.35 609.4 7.45 109 3.72 Spot6 0.06267 0.00063 0.1031 0.00162 0.89071 0.01384 0.03031 0.00033 697.2 21.28 632.6 9.48 646.8 7.43 603.5 6.45 91 2.62 Spot11 0.07096 0.00074 0.10131 0.00156 0.99105 0.01546 0.03736 0.00046 956.4 21.27 622.1 9.16 699.3 7.88 741.3 8.91 65 1.56 Spot3 0.06236 0.00062 0.09991 0.00141 0.85895 0.01201 0.03342 0.00037 686.4 21.2 613.9 8.29 629.6 6.56 664.4 7.24 89 0.74 Spot1 0.06255 0.00062 0.09967 0.00144 0.85957 0.01222 0.0282 0.00028 693.1 20.89 612.5 8.43 629.9 6.67 562.1 5.53 88 0.56 Spot5 0.06007 0.00059 0.09879 0.00147 0.81814 0.01201 0.03019 0.00031 606.1 21.23 607.3 8.62 607 6.71 601.2 6.03 100 -0.06 Spot4 0.06268 0.00065 0.09847 0.00139 0.85088 0.01204 0.03437 0.00048 697.5 21.98 605.5 8.15 625.1 6.61 683.1 9.28 87 -0.28 Spot7 0.06828 0.00068 0.09825 0.00146 0.92484 0.01364 0.03145 0.00033 877.1 20.46 604.1 8.57 664.9 7.2 625.9 6.5 69 -0.43 Spot10 0.06069 0.0006 0.09756 0.00139 0.81632 0.01146 0.02934 0.00034 628.1 21.14 600.1 8.16 606 6.41 584.5 6.64 96 -0.94 Spot2 0.06349 0.00063 0.09564 0.00141 0.83716 0.01219 0.02998 0.0003 724.8 20.79 588.8 8.32 617.6 6.74 597.1 5.88 81 -2.28 Spot9 0.06048 0.0006 0.09361 0.00132 0.78052 0.01087 0.02986 0.00039 620.7 21.25 576.9 7.81 585.8 6.2 594.8 7.68 93 -3.95
kw Mean, n=11 U-Pb Concordia (isoptope ratios): Groups seperated based on σ from mean 605.0 18 (±1σ) MSWD=4.9
Weighted Av. (assigned internal errors) 95% conf. 1.96σ: Groups seperated based on σ kw Mean, n=11 608.0 12 [2.0%] MSWD=4.6 from mean GJ GJ1 0.05958 0.00074 0.09800 0.00140 0.80510 0.01262 0.02857 0.00092 588.5 26.8 602.7 8.2 599.7 7.1 569.4 18.2 102 GJ2 0.06023 0.00069 0.09733 0.00145 0.80820 0.01255 0.03079 0.00075 611.9 24.5 598.8 8.5 601.4 7.1 613.0 14.8 98 GJ3 0.05961 0.00069 0.09800 0.00144 0.80538 0.01247 0.03014 0.00079 589.6 24.9 602.7 8.5 599.9 7.0 600.2 15.4 102 GJ4 0.06048 0.00071 0.09740 0.00142 0.81201 0.01260 0.03015 0.00083 620.7 25.2 599.1 8.4 603.6 7.1 600.4 16.2 97 GJ5 0.06012 0.00068 0.09776 0.00145 0.81025 0.01251 0.03215 0.00078 607.9 24.4 601.3 8.5 602.6 7.0 639.7 15.3 99 GJ6 0.06011 0.00069 0.09765 0.00145 0.80921 0.01256 0.03064 0.00080 607.6 24.5 600.6 8.5 602.0 7.1 610.0 15.7 99 GJ7 0.05964 0.00068 0.09801 0.00146 0.80584 0.01249 0.03103 0.00075 590.6 24.4 602.7 8.6 600.1 7.0 617.6 14.7 102 GJ Mean 603.0 18 [2σ] 601.1 6.3 [2σ] 601.3 5.2 [2σ] Weighted Av. 95% conf. (1.96σ) GJ Mean (GEMOC) 607.7 4.3 [2σ] 600.7 1.1[2σ] 602.0 1.0 [2σ] Plesovice Ples1 0.05322 0.00065 0.05429 0.00078 0.39839 0.00620 0.01830 0.00034 338.3 27.22 340.8 4.75 340.5 4.5 366.5 6.75 101 Ples2 0.05302 0.00059 0.05424 0.00080 0.39650 0.00605 0.01818 0.00027 329.7 24.93 340.5 4.9 339.1 4.4 364.2 5.31 103 Ples Mean 334.0 36 [2σ] 340.7 6.7 [2σ) 339.8 6.2 [2σ] Weighted Av. 95% conf. (1.96σ) Ples Mean (Slama et al., 2008) 339.2 0.25 [2σ] 337.1 0.37 [2σ] 337.3 0.11 [2σ]
381 Table 13: U-Pb isotope data from Idah Suite (id) zircon grains analysed by LA-ICPMS (Appendix a1). These values have been numerically arranged to highlight the maximum and minimum values. Consequently, the spot numbers are no longer in subsequent experimental time. However, spot numbers 1-9 and 10-20 correspond to Block 1 (GJ standards 1-7) and Block 2 (GJ standards 6-12) respectively (see standard Table 13-continued). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ 207Pb/206Pb ±1σ 206Pb/238U ±1σ 207Pb/235U ±1σ 208Pb/232Th ±1σ Conc. σ from No. (Ma) (Ma) (Ma) (Ma) mean Idah Suite (id)-sample id159, n=20 Spot4 0.05965 0.0021 0.10383 0.00216 0.85358 0.03083 0.02692 0.00284 590.8 74.6 636.8 12.6 626.6 16.9 537.0 55.9 108 2.30 Spot17 0.05965 0.0021 0.10383 0.00216 0.85358 0.03083 0.02692 0.00284 590.8 74.6 636.8 12.6 626.6 16.9 537.0 55.9 108 2.30 Spot11 0.06414 0.0025 0.10125 0.00211 0.89528 0.03504 0.03506 0.00456 746.4 80.4 621.7 12.4 649.2 18.8 696.5 89.0 83 1.11 Spot18 0.06414 0.0025 0.10125 0.00211 0.89528 0.03504 0.03506 0.00456 746.4 80.4 621.7 12.4 649.2 18.8 696.5 89.0 83 1.11 Spot7 0.06504 0.00552 0.10006 0.00349 0.89693 0.07321 0.01642 0.00368 775.6 169.0 614.8 20.5 650.1 39.2 329.2 73.3 79 0.34 Spot14 0.06000 0.00241 0.10002 0.00211 0.8273 0.03325 0.02771 0.00384 603.7 84.7 614.5 12.4 612.1 18.5 552.5 75.5 102 0.53 Spot9 0.05888 0.00295 0.09973 0.00228 0.80945 0.03967 0.03574 0.00662 562.6 105.6 612.8 13.4 602.1 22.3 709.8 129.2 109 0.37 Spot19 0.05888 0.00295 0.09973 0.00228 0.80945 0.03967 0.03574 0.00662 562.6 105.6 612.8 13.4 602.1 22.3 709.8 129.2 109 0.37 Spot6 0.06192 0.00285 0.09963 0.00229 0.85041 0.03888 0.0285 0.00433 671.4 95.5 612.2 13.4 624.9 21.3 568.0 85.1 91 0.32 Spot1 0.06262 0.00079 0.09846 0.0014 0.84991 0.01325 0.03377 0.00088 695.5 26.8 605.4 8.2 624.6 7.3 671.3 17.3 87 -0.30 Spot20 0.06262 0.00079 0.09846 0.0014 0.84991 0.01325 0.03377 0.00088 695.5 26.8 605.4 8.2 624.6 7.3 671.3 17.3 87 -0.30 Spot8 0.05948 0.00296 0.09816 0.00236 0.80498 0.03964 0.02488 0.00398 584.7 104.6 603.6 13.9 599.6 22.3 496.7 78.5 103 -0.31 Spot5 0.06220 0.00295 0.09784 0.00233 0.83889 0.03978 0.02563 0.00378 681.1 98.0 601.7 13.7 618.5 22.0 511.5 74.5 88 -0.45 Spot16 0.06059 0.00285 0.09763 0.00218 0.81531 0.03765 0.0332 0.00607 624.8 98.2 600.5 12.8 605.4 21.1 660.1 118.8 96 -0.58 Spot2 0.06172 0.00263 0.09734 0.00205 0.82794 0.03481 0.03943 0.00616 664.4 88.8 598.8 12.0 612.5 19.3 781.7 119.7 90 -0.76 Spot10 0.07321 0.00562 0.09714 0.00312 0.98022 0.07246 0.02131 0.00448 1019.9 148.0 597.6 18.4 693.7 37.2 426.2 88.7 59 -0.56 Spot15 0.07115 0.0059 0.09693 0.00327 0.95064 0.07547 0.02731 0.00609 961.7 160.7 596.4 19.2 678.4 39.3 544.6 119.9 62 -0.60 Spot3 0.05980 0.0022 0.09542 0.00188 0.78647 0.02892 0.03713 0.00495 596.4 77.6 587.5 11.1 589.2 16.4 737.0 96.4 99 -1.84 Spot13 0.06410 0.00421 0.0952 0.00271 0.84117 0.05359 0.02651 0.00528 744.9 133.0 586.2 15.9 619.8 29.6 528.8 104.0 79 -1.36 Spot12 0.06192 0.00286 0.09517 0.00219 0.81239 0.03722 0.02428 0.00365 671.4 96.0 586.1 12.9 603.8 20.9 484.8 72.1 87 -1.69
id Mean, n=20 U-Pb Concordia (isoptope ratios): Groups seperated based on σ from mean 616.6 8.7 (±1σ) MSWD=1.03
Weighted Av. (assigned internal errors) 95% conf. 1.96σ: Groups seperated based on σ id Mean, n=20 607.9 6.6 [1.1%] MSWD=1.3 from mean
382 Table 13 (continued): U-Pb absolute age data for zircon standards analysed by LA-ICPMS (Appendix a1). These standards have recognised age values (see Jackson et al., 2004 and Slama et al, 2008), which are used to tie the unknown zircon values by linear modelling (standards provide error bounds on unknown values). Block 1 (GJ standards 1-7) and Block 2 (GJ standards 6-12) correspond to absolute age values 1-9 and 10-20 respectively (see id ages Table 13). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 206Pb/238U 207Pb/235U 208Pb/232Th 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ ±1σ ±1σ ±1σ ±1σ Conc. No. (Ma) (Ma) (Ma) (Ma) Idah Suite (id)-sample id159, n=20 GJ GJ1 0.06017 0.00069 0.09858 0.00130 0.81784 0.01135 0.03181 0.00079 609.8 24.4 606.1 7.6 606.8 6.3 632.9 15.4 99 GJ2 0.06021 0.00068 0.09833 0.00130 0.81618 0.01132 0.03037 0.00074 611.1 24.3 604.6 7.6 605.9 6.3 604.8 14.5 99 GJ3 0.06346 0.00072 0.09794 0.00131 0.85690 0.01205 0.05356 0.00119 723.6 24.0 602.3 7.7 628.4 6.6 1054.6 22.8 83 GJ4 0.05969 0.00069 0.09788 0.00132 0.80547 0.01142 0.03038 0.00079 592.9 24.2 601.9 7.7 599.9 6.4 605.0 15.4 102 GJ5 0.05991 0.00069 0.09719 0.00131 0.80279 0.01146 0.03034 0.00080 600.4 24.9 597.9 7.7 598.4 6.5 604.1 15.8 100 GJ6 0.06166 0.00156 0.09725 0.00163 0.82671 0.02153 0.03036 0.00282 662.4 53.3 598.3 9.6 611.8 12.0 604.4 55.3 90 GJ7 0.06006 0.00153 0.09961 0.00167 0.82479 0.02163 0.03181 0.00295 605.6 54.1 612.1 9.8 610.7 12.0 632.9 57.8 101 GJ8 0.05951 0.00155 0.09856 0.00167 0.80867 0.02162 0.03202 0.00306 585.8 55.4 606.0 9.8 601.7 12.1 637.1 59.8 103 GJ9 0.06159 0.00290 0.09749 0.00215 0.82772 0.03818 0.02933 0.00531 660.0 97.8 599.7 12.6 612.3 21.2 584.2 104.3 91 GJ10 0.05946 0.00256 0.09796 0.00209 0.80286 0.03423 0.03269 0.00556 583.8 90.8 602.4 12.3 598.4 19.3 650.2 108.8 103 GJ11 0.05881 0.00263 0.09862 0.00214 0.79944 0.03532 0.03257 0.00580 559.9 94.7 606.3 12.5 596.5 19.9 647.9 113.5 108 GJ12 0.06086 0.00272 0.09798 0.00212 0.82208 0.03621 0.03079 0.00548 634.4 93.3 602.6 12.5 609.2 20.2 613.0 107.5 95 GJ Mean 626.0 31 [2σ] 603.2 5.2 [2σ] 607.5 6.5 [2σ] Weighted Av. 95% conf. (1.96σ) GJ Mean (GEMOC) 607.7 4.3 [2σ] 600.7 1.1[2σ] 602.0 1.0 [2σ] Plesovice ples1 0.05283 0.00135 0.05299 0.00089 0.38603 0.01021 0.01776 0.00155 321.6 57.0 332.9 5.5 331.5 7.5 355.9 30.7 104 ples2 0.05362 0.00137 0.05304 0.00090 0.39210 0.01038 0.01673 0.00146 354.8 56.8 333.2 5.5 335.9 7.6 335.3 29.0 94 ples3 0.05305 0.00218 0.05457 0.00114 0.39909 0.01632 0.01789 0.00281 330.9 90.6 342.5 7.0 341.0 11.9 358.4 55.8 104 ples4 0.05299 0.00305 0.05415 0.00133 0.39559 0.02209 0.01676 0.00363 328.3 125.5 340.0 8.1 338.4 16.1 336.0 72.1 104 Ples Mean 336.0 69 [2σ] 336.0 6.1 [2σ) 335.2 9.1 [2σ] Weighted Av. 95% conf. (1.96σ) Ples Mean (Slama et al., 2008) 339.2 0.25 [2σ] 337.1 0.37 [2σ] 337.3 0.11 [2σ]
383 Table 14: U-Pb isotope data from Al Khushaymiyah Suite (ky) zircon grains analysed by LA-ICPMS (Appendix a1). These values have been numerically arranged to highlight the maximum and minimum values. Consequently, the spot numbers are no longer in subsequent experimental time. However, spot numbers 1-12 and 13-24 correspond to Block 1 (GJ standards 1-7) and Block 2 (GJ standards 6-12) respectively (see standard Table 14-continued). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ 207Pb/206Pb ±1σ 206Pb/238U ±1σ 207Pb/235U ±1σ 208Pb/232Th ±1σ Conc. σ from No. (Ma) (Ma) (Ma) (Ma) mean Al Khushaymiyah Suite (ky)-sample ky129, n=24 Spot3 0.06292 0.00069 0.10156 0.00145 0.88102 0.01283 0.03240 0.00059 705.6 23.0 623.5 8.5 641.5 6.9 644.5 11.6 88 2.63 Spot20 0.06337 0.00134 0.10097 0.00156 0.88215 0.01991 0.03238 0.00230 720.8 44.3 620.1 9.2 642.1 10.7 644.0 45.0 86 2.06 Spot22 0.06149 0.00143 0.10077 0.00159 0.85426 0.02082 0.03001 0.00241 656.5 49.3 618.9 9.3 627.0 11.4 597.6 47.2 94 1.90 Spot18 0.06257 0.00172 0.10073 0.00178 0.86883 0.02490 0.02748 0.00258 693.5 57.6 618.7 10.4 634.9 13.5 548.0 50.7 89 1.68 Spot19 0.06492 0.00144 0.10062 0.00157 0.90061 0.02107 0.03181 0.00244 771.8 46.1 618.1 9.2 652.1 11.3 633.0 47.8 80 1.84 Spot9 0.06204 0.00085 0.09959 0.00141 0.85175 0.01393 0.03227 0.00113 675.5 29.1 612.0 8.3 625.6 7.6 642.0 22.2 91 1.30 Spot24 0.06560 0.00187 0.09890 0.00168 0.89442 0.02600 0.03064 0.00311 793.8 58.7 608.0 9.9 648.7 13.9 610.0 61.0 77 0.69 Spot8 0.06242 0.00089 0.09883 0.00141 0.85043 0.01425 0.03116 0.00098 688.5 30.2 607.6 8.3 624.9 7.8 620.2 19.2 88 0.77 Spot10 0.06055 0.00084 0.09873 0.00147 0.82415 0.01402 0.02970 0.00105 623.3 29.7 607.0 8.6 610.4 7.8 591.7 20.5 97 0.67 Spot11 0.06163 0.00153 0.09810 0.00168 0.83348 0.02190 0.02886 0.00232 661.3 52.2 603.3 9.9 615.5 12.1 575.1 45.6 91 0.21 Spot4 0.06407 0.00070 0.09805 0.00140 0.86608 0.01263 0.03131 0.00059 743.8 22.9 603.0 8.2 633.4 6.9 623.1 11.5 81 0.22 Spot21 0.06083 0.00141 0.09805 0.00158 0.82226 0.02010 0.02948 0.00233 633.2 49.1 603.0 9.3 609.3 11.2 587.3 45.8 95 0.19 Spot13 0.07115 0.00109 0.09782 0.00149 0.95953 0.01743 0.03144 0.00144 961.7 30.9 601.6 8.7 683.1 9.0 625.7 28.3 63 0.04 Spot17 0.06413 0.00108 0.09750 0.00148 0.86208 0.01658 0.03061 0.00166 746.0 35.3 599.8 8.7 631.3 9.0 609.4 32.5 80 -0.16 Spot5 0.06487 0.00071 0.09719 0.00139 0.86926 0.01277 0.02840 0.00056 770.3 23.0 597.9 8.2 635.2 6.9 565.9 11.1 78 -0.41 Spot14 0.06288 0.00097 0.09718 0.00147 0.84239 0.01531 0.02989 0.00137 704.1 32.5 597.8 8.6 620.5 8.4 595.3 26.9 85 -0.40 Spot23 0.06693 0.00115 0.09641 0.00148 0.88964 0.01747 0.03059 0.00165 835.6 35.5 593.3 8.7 646.2 9.4 609.1 32.3 71 -0.91 Spot15 0.06355 0.00101 0.09605 0.00145 0.84143 0.01562 0.03140 0.00153 726.5 33.5 591.2 8.5 619.9 8.6 624.9 30.0 81 -1.17 Spot2 0.06367 0.00071 0.09591 0.00138 0.84200 0.01256 0.03172 0.00062 730.8 23.6 590.4 8.1 620.2 6.9 631.3 12.1 81 -1.33 Spot16 0.06303 0.00132 0.09584 0.00158 0.83281 0.01918 0.02668 0.00164 709.3 44.1 590.0 9.3 615.2 10.6 532.3 32.2 83 -1.21 Spot1 0.06233 0.00107 0.09549 0.00153 0.82060 0.01642 0.02344 0.00076 685.6 36.3 587.9 9.0 608.4 9.2 468.2 15.1 86 -1.48 Spot7 0.06947 0.00082 0.09522 0.00139 0.91188 0.01409 0.02898 0.00069 912.6 24.1 586.3 8.2 658.1 7.5 577.5 13.5 64 -1.82 Spot12 0.06891 0.00105 0.09477 0.00143 0.90030 0.01623 0.03035 0.00138 895.9 31.1 583.7 8.4 651.9 8.7 604.2 27.1 65 -2.08 Spot6 0.06426 0.00085 0.09428 0.00142 0.83522 0.01403 0.03005 0.00084 750.1 27.8 580.8 8.4 616.5 7.8 598.5 16.5 77 -2.43
ky Mean, n=24 U-Pb Concordia (isoptope ratios): Groups seperated based on σ from mean 609.7 8.5 (±1σ) MSWD=1.7
Weighted Av. (assigned internal errors) 95% conf. 1.96σ: Groups seperated based on σ ky Mean, n=24 601.2 5.2 [0.87%] MSWD=2 from mean
384 Table 14 (continued): U-Pb absolute age data for zircon standards analysed by LA-ICPMS (Appendix a1). These standards have recognised age values (see Jackson et al., 2004 and Slama et al, 2008), which are used to tie the unknown zircon values by linear modelling (standards provide error bounds on unknown values). Block 1 (GJ standards 1-7) and Block 2 (GJ standards 6-12) correspond to absolute age values 1-12 and 13-24 respectively (see ky ages Table 14). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 206Pb/238U 207Pb/235U 208Pb/232Th 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ ±1σ ±1σ ±1σ ±1σ Conc. No. (Ma) (Ma) (Ma) (Ma) Al khushaymiyah Suite (ky)-sample ky129, n=24 GJ GJ1 0.06061 0.00071 0.09953 0.00140 0.83172 0.01239 0.03387 0.00095 625.4 25.2 611.6 8.2 614.6 6.9 673.3 18.5 98 GJ2 0.06055 0.00071 0.09728 0.00137 0.81221 0.01212 0.03002 0.00082 623.4 25.0 598.5 8.1 603.7 6.8 597.9 16.0 96 GJ3 0.06010 0.00070 0.09662 0.00136 0.80073 0.01191 0.02987 0.00079 607.3 24.9 594.6 8.0 597.2 6.7 594.8 15.5 98 GJ4 0.05923 0.00070 0.09797 0.00139 0.80000 0.01207 0.03067 0.00087 575.4 25.6 602.5 8.1 596.8 6.8 610.6 17.1 105 GJ5 0.06010 0.00071 0.09730 0.00138 0.80623 0.01218 0.03011 0.00085 607.2 25.4 598.5 8.1 600.3 6.9 599.6 16.6 99 GJ6 0.05958 0.00090 0.09859 0.00148 0.80981 0.01449 0.03154 0.00149 588.3 32.6 606.1 8.7 602.3 8.1 627.7 29.2 103 GJ7 0.06072 0.00093 0.09796 0.00147 0.82002 0.01473 0.03096 0.00148 629.2 32.5 602.5 8.6 608.1 8.2 616.2 29.1 96 GJ8 0.06020 0.00093 0.09699 0.00146 0.80504 0.01463 0.03003 0.00148 610.9 33.2 596.8 8.6 599.7 8.2 598.1 29.1 98 GJ9 0.06034 0.00097 0.09732 0.00146 0.80954 0.01500 0.03098 0.00159 615.7 34.2 598.7 8.6 602.2 8.4 616.7 31.2 97 GJ10 0.05993 0.00097 0.09699 0.00146 0.80133 0.01494 0.02991 0.00155 601.0 34.5 596.7 8.6 597.6 8.4 595.7 30.5 99 GJ11 0.05997 0.00110 0.09777 0.00151 0.80843 0.01658 0.02938 0.00178 602.6 39.1 601.3 8.9 601.6 9.3 585.3 35.0 100 GJ12 0.06033 0.00110 0.09771 0.00151 0.81269 0.01668 0.03231 0.00193 615.4 39.1 601.0 8.9 604.0 9.3 642.8 37.9 98 GJ Mean 608.0 17 [2σ] 600.7 4.8 [2σ] 602.3 4.3 [2σ] Weighted Av. 95% conf. (1.96σ) GJ Mean (GEMOC) 607.7 4.3 [2σ] 600.7 1.1[2σ] 602.0 1.0 [2σ] Plesovice ples1 0.05290 0.00061 0.05471 0.00077 0.39899 0.00591 0.01630 0.00033 324.3 25.83 343.4 4.72 340.9 4.29 326.9 6.55 106 ples2 0.05322 0.00062 0.05419 0.00077 0.39764 0.00594 0.01604 0.00033 338 25.91 340.2 4.7 339.9 4.32 321.6 6.61 101 ples3 0.05361 0.00085 0.05497 0.00083 0.40631 0.00755 0.01741 0.00084 354.7 35.63 345 5.1 346.2 5.45 348.8 16.7 97 ples4 0.05319 0.00089 0.05441 0.00082 0.39897 0.00760 0.01680 0.00087 336.9 37.2 341.5 5.04 340.9 5.52 336.8 17.24 101 Ples Mean 336.0 29 [2σ] 342.5 4.8 [2σ) 341.6 4.7 [2σ] Weighted Av. 95% conf. (1.96σ) Ples Mean (Slama et al., 2008) 339.2 0.25 [2σ] 337.1 0.37 [2σ] 337.3 0.11 [2σ]
385 Anorogenic Magmatism (<600 Ma) Post-Arabian Shield Terrane Accretion
386 Table 15: U-Pb isotope data from Malik Granite (kg) zircon grains analysed by LA-ICPMS (Appendix a1). These values have been numerically arranged to highlight the maximum and minimum values. Consequently, the spot numbers are no longer in subsequent experimental time. However, spot numbers 1-11 correspond to Block 1 (GJ standards 1-7) respectively. Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 206Pb/238U 207Pb/235U 208Pb/232Th σ from 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ ±1σ ±1σ ±1σ ±1σ Conc. No. (Ma) (Ma) (Ma) (Ma) mean Malik Granite (kg)-sample kg150, n=11 Spot8 0.06233 0.00093 0.09809 0.00138 0.85513 0.01322 0.03172 0.00076 635.5 25.6 609.1 8.1 628.6 7.0 641.6 25.6 96 1.17 Spot3 0.06028 0.00072 0.09809 0.00138 0.81513 0.01222 0.03086 0.00080 613.5 25.6 603.2 8.1 605.3 6.8 614.4 15.8 98 0.44 Spot7 0.06185 0.00111 0.09701 0.00137 0.84012 0.01492 0.02788 0.00099 713.4 29.4 602.9 8.7 621.7 7.7 623.8 18.8 85 0.38 Spot4 0.06236 0.00146 0.09753 0.00159 0.83843 0.02042 0.03328 0.00259 686.4 49.2 599.9 9.3 618.3 11.3 661.7 50.7 87 0.03 Spot5 0.06486 0.00095 0.09747 0.00150 0.87159 0.01543 0.02765 0.00100 769.6 30.5 599.6 8.8 636.4 8.4 555.9 19.7 78 -0.01 Spot6 0.06019 0.00085 0.09777 0.00141 0.82856 0.01325 0.03000 0.00171 627.6 26.2 599.6 8.0 608.2 9.6 599.2 17.6 96 -0.01 Spot11 0.06321 0.00078 0.09834 0.00240 0.83108 0.01261 0.02999 0.00147 769.6 30.5 599.6 8.8 611.5 8.8 611.8 36.6 78 -0.01 Spot1 0.06040 0.00071 0.09713 0.00136 0.80873 0.01201 0.03140 0.00075 617.9 25.3 597.6 8.0 601.7 6.7 624.9 14.7 97 -0.26 Spot2 0.06431 0.00080 0.09701 0.00147 0.86012 0.01392 0.02993 0.00082 751.8 25.9 596.9 8.7 630.2 7.6 596.0 16.0 79 -0.32 Spot9 0.06024 0.00081 0.09823 0.00139 0.81892 0.02012 0.03013 0.00118 666.2 39.2 593.7 9.3 603.1 10.1 607.0 29.4 89 -0.64 Spot10 0.06004 0.00079 0.09574 0.00140 0.80707 0.01569 0.03098 0.00114 723.6 28.4 592.5 8.2 618.9 11.3 616.5 15.7 82 -0.87
kg Mean, n=11 U-Pb Concordia (isoptope ratios): Groups seperated based on σ from mean 600.3 8.6 (±1σ) MSWD=0.29
Weighted Av. (assigned internal errors) 95% conf. 1.96σ: Groups seperated based on σ kg Mean, n=11 599.6 5 [0.84%] MSWD=0.76 from mean GJ GJ1 0.06069 0.00074 0.09598 0.00137 0.80295 0.01226 0.03005 0.00097 628.3 25.97 590.8 8.03 598.5 6.9 598.4 19.11 94 GJ2 0.05961 0.00073 0.09853 0.00140 0.80961 0.01244 0.03063 0.00100 589.3 26.42 605.8 8.23 602.2 6.98 609.8 19.63 103 GJ3 0.06012 0.00075 0.09865 0.00141 0.81758 0.01268 0.02960 0.00102 607.9 26.76 606.5 8.26 606.7 7.08 589.7 19.97 100 GJ4 0.06031 0.00074 0.09764 0.00139 0.81182 0.01241 0.03153 0.00100 614.7 26.14 600.6 8.15 603.5 6.95 627.4 19.61 98 GJ5 0.05999 0.00073 0.09782 0.00139 0.80902 0.01236 0.03220 0.00101 603.4 26.18 601.6 8.15 601.9 6.94 640.7 19.84 100 GJ6 0.06024 0.00081 0.09766 0.00140 0.81111 0.01317 0.03013 0.00118 612.3 28.88 600.7 8.23 603.1 7.38 600.1 23.25 98 GJ7 0.06004 0.00079 0.09741 0.00141 0.80632 0.01292 0.03098 0.00114 605 28.08 599.2 8.26 600.4 7.26 616.6 22.4 100 GJ Mean 609.0 20 [2σ] 600.7 6.1 [2σ] 602.3 5.2 [2σ] Weighted Av. 95% conf. (1.96σ) GJ Mean (GEMOC) 607.7 4.3 [2σ] 600.7 1.1[2σ] 602.0 1.0 [2σ] Plesovic Ples1 0.05293 0.00062 0.05302 0.00071 0.37960 0.00533 0.01666 0.00038 327.7 25.5 329.4 5.6 328.6 4.9 332.9 7.9 100 Ples2 0.05298 0.00065 0.05205 0.00074 0.38020 0.00584 0.01671 0.00040 328.0 27.5 327.1 4.5 327.2 4.3 334.9 8.0 100 Ples Mean 328.0 37 [2σ] 328.0 6.3 [2σ) 327.8 6.3 [2σ] Weighted Av. 95% conf. (1.96σ) Ples Mean (Slama et al., 2008) 339.2 0.25 [2σ] 337.1 0.37 [2σ] 337.3 0.11 [2σ]
387 Table 16: U-Pb isotope data from Admar Suite (ad) zircon grains analysed by LA-ICPMS (Appendix a1). These values have been numerically arranged to highlight the maximum and minimum values. Consequently, the spot numbers are no longer in subsequent experimental time. However, spot numbers 1-10, 11-22 and 23-33 correspond to Block 1 (GJ standards 1-7), Block 2 (GJ standards 6-12) and Block 3 (GJ standards 11-17) respectively (see standard Table 16-continued). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 206Pb/238U 207Pb/235U 208Pb/232Th σ from 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ ±1σ ±1σ ±1σ ±1σ Conc. No. (Ma) (Ma) (Ma) (Ma) mean Admar Suite (ad)-sample ad194, n=33 Spot33 0.06091 0.00453 0.10160 0.00263 0.85190 0.06133 0.03004 0.00231 636.0 152.4 623.8 15.4 625.7 33.6 598.2 45.4 98 1.60 Spot25 0.05867 0.00159 0.10009 0.00160 0.80882 0.02229 0.03178 0.00100 554.8 57.9 614.9 9.4 601.8 12.5 632.4 19.5 111 1.68 Spot1 0.06124 0.00188 0.09977 0.00161 0.84245 0.02592 0.03314 0.00081 647.8 64.7 613.1 9.5 620.5 14.3 659.0 15.9 95 1.47 Spot32 0.06352 0.00462 0.09962 0.00246 0.87188 0.06156 0.03612 0.00238 725.8 147.2 612.2 14.4 636.6 33.4 717.1 46.4 84 0.90 Spot7 0.06116 0.00278 0.09933 0.00192 0.83760 0.03730 0.03396 0.00128 644.7 94.9 610.5 11.2 617.8 20.6 675.0 24.9 95 1.01 Spot4 0.05817 0.00343 0.09901 0.00201 0.79408 0.04592 0.03183 0.00142 535.7 124.5 608.6 11.8 593.5 26.0 633.3 27.8 114 0.80 Spot23 0.06239 0.00383 0.09860 0.00218 0.84814 0.05081 0.03118 0.00152 687.4 125.9 606.2 12.8 623.6 27.9 620.5 29.9 88 0.55 Spot28 0.05954 0.00268 0.09860 0.00189 0.80849 0.03586 0.02972 0.00126 586.8 94.8 606.2 11.1 601.6 20.1 592.0 24.7 103 0.63 Spot10 0.05825 0.00391 0.09850 0.00237 0.79034 0.05171 0.03030 0.00136 538.5 141.1 605.6 13.9 591.4 29.3 603.2 26.8 112 0.46 Spot27 0.06446 0.00425 0.09847 0.00230 0.87448 0.05595 0.03164 0.00181 756.7 133.3 605.5 13.5 638.0 30.3 629.7 35.4 80 0.47 Spot6 0.05936 0.00299 0.09823 0.00192 0.80386 0.03965 0.03019 0.00125 580.3 105.8 604.0 11.3 599.0 22.3 601.2 24.5 104 0.43 Spot29 0.06186 0.00229 0.09803 0.00170 0.83532 0.03047 0.03176 0.00133 669.2 77.2 602.9 10.0 616.6 16.9 632.0 26.1 90 0.37 Spot31 0.06196 0.00223 0.09782 0.00167 0.83495 0.02957 0.03305 0.00144 672.8 75.1 601.6 9.8 616.4 16.4 657.3 28.2 89 0.25 Spot26 0.05981 0.00372 0.09772 0.00222 0.80526 0.04865 0.03177 0.00189 596.7 129.3 601.0 13.1 599.8 27.4 632.1 37.0 101 0.14 Spot2 0.05740 0.00286 0.09766 0.00184 0.77280 0.03788 0.03178 0.00116 506.5 106.5 600.7 10.8 581.4 21.7 632.3 22.8 119 0.14 Spot9 0.05853 0.00258 0.09766 0.00177 0.78815 0.03422 0.02917 0.00105 549.7 93.4 600.7 10.4 590.1 19.4 581.2 20.7 109 0.15 Spot11 0.05888 0.00258 0.09761 0.00178 0.79244 0.03409 0.03007 0.00113 562.6 92.5 600.4 10.5 592.6 19.3 598.8 22.2 107 0.12 Spot13 0.05683 0.00306 0.09749 0.00199 0.76389 0.04015 0.03033 0.00137 484.2 115.5 599.7 11.7 576.3 23.1 604.0 26.8 124 0.04 Spot19 0.05983 0.00280 0.09749 0.00181 0.80408 0.03706 0.02751 0.00110 597.5 98.1 599.7 10.6 599.1 20.9 548.4 21.6 100 0.05 Spot12 0.05943 0.00399 0.09738 0.00246 0.79657 0.05194 0.03168 0.00171 583.0 139.5 599.0 14.5 594.9 29.4 630.5 33.4 103 -0.01 Spot15 0.06436 0.00542 0.09737 0.00249 0.86373 0.07095 0.03609 0.00224 753.4 168.4 599.0 14.6 632.2 38.7 716.5 43.8 80 -0.01 Spot24 0.06138 0.00317 0.09693 0.00197 0.82019 0.04155 0.02903 0.00125 652.4 107.2 596.4 11.6 608.2 23.2 578.5 24.6 91 -0.24 Spot5 0.06249 0.00411 0.09691 0.00235 0.83477 0.05316 0.03183 0.00174 690.8 134.2 596.3 13.8 616.3 29.4 633.3 34.2 86 -0.21 Spot22 0.06439 0.00389 0.09691 0.00223 0.86031 0.05055 0.02464 0.00145 754.6 122.4 596.3 13.1 630.3 27.6 492.0 28.5 79 -0.22 Spot18 0.06095 0.00119 0.09640 0.00138 0.81001 0.01682 0.02784 0.00056 637.6 41.5 593.3 8.1 602.5 9.4 555.1 11.0 93 -0.73 Spot3 0.05841 0.00207 0.09636 0.00160 0.77594 0.02716 0.03389 0.00167 545.3 75.5 593.0 9.4 583.2 15.5 673.6 32.6 109 -0.66 Spot14 0.06213 0.00130 0.09624 0.00141 0.82425 0.01816 0.02937 0.00057 678.7 44.2 592.3 8.3 610.4 10.1 585.1 11.3 87 -0.83 Spot16 0.05948 0.00320 0.09567 0.00196 0.78420 0.04100 0.02994 0.00120 584.6 112.6 589.0 11.5 587.9 23.3 596.3 23.5 101 -0.88 Spot8 0.06177 0.00260 0.09550 0.00173 0.81334 0.03379 0.02973 0.00107 666.0 87.8 588.0 10.2 604.3 18.9 592.2 21.0 88 -1.10 Spot30 0.06351 0.00226 0.09544 0.00164 0.83451 0.02951 0.03060 0.00103 725.3 73.7 587.6 9.7 616.1 16.3 609.1 20.3 81 -1.20 Spot20 0.06232 0.00376 0.09529 0.00200 0.81863 0.04849 0.02814 0.00133 685.1 124.0 586.7 11.7 607.3 27.1 560.9 26.1 86 -1.06 Spot21 0.06005 0.00233 0.09510 0.00165 0.78732 0.03026 0.02945 0.00084 605.4 81.6 585.6 9.7 589.7 17.2 586.6 16.5 97 -1.40 Spot17 0.06543 0.00310 0.09493 0.00183 0.85609 0.03985 0.02990 0.00121 788.1 96.6 584.6 10.8 628.0 21.8 595.5 23.7 74 -1.35
ad Mean, n=33 U-Pb Concordia (isoptope ratios): Groups seperated based on σ from mean 602.5 5.3 (±1σ) MSWD=0.50
ad Mean, n=33 Weighted Av. (assigned internal errors) 95% conf. 1.96σ: Groups seperated based on σ from 599.2 3.8 [0.63%] MSWD=0.68 mean
388 Table 16 (continued): U-Pb absolute age data for zircon standards analysed by LA-ICPMS (Appendix a1). These standards have recognised age values (see Jackson et al., 2004 and Slama et al, 2008), which are used to tie the unknown zircon values by linear modelling (standards provide error bounds on unknown values). Block 1 (GJ standards 1-7), Block 2 (GJ standards 6-12) and Block 3 (GJ standards 11-17) correspond to absolute age values 1-10, 11-22 and 23-33 respectively (see ad ages Table 16). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 206Pb/238U 207Pb/235U 208Pb/232Th 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ ±1σ ±1σ ±1σ ±1σ Conc. No. (Ma) (Ma) (Ma) (Ma) Admar Suite (ad)-sample ad194, n=33 GJ GJ1 0.05817 0.00146 0.09880 0.00155 0.79238 0.02042 0.04049 0.00367 535.5 54.7 607.4 9.1 592.5 11.6 802.3 71.4 113 GJ2 0.05964 0.00113 0.09853 0.00137 0.80996 0.01626 0.02995 0.00229 590.4 40.6 605.8 8.0 602.4 9.1 596.4 45.0 103 GJ3 0.05878 0.0011 0.09698 0.00136 0.78588 0.01564 0.0293 0.00226 559.1 40.1 596.7 8.0 588.8 8.9 583.6 44.3 107 GJ4 0.06147 0.00115 0.09697 0.00137 0.82168 0.01641 0.03219 0.00234 655.6 39.7 596.6 8.1 609.0 9.2 640.5 45.9 91 GJ5 0.06205 0.00122 0.09844 0.00139 0.84218 0.0174 0.03326 0.00272 675.9 41.6 605.3 8.1 620.4 9.6 661.3 53.1 90 GJ6 0.06018 0.00116 0.09764 0.00138 0.81015 0.01654 0.03189 0.00259 610.1 41.0 600.6 8.1 602.5 9.3 634.4 50.7 98 GJ7 0.05952 0.00136 0.09700 0.00147 0.79568 0.01889 0.0296 0.00292 586.0 48.7 596.8 8.7 594.4 10.7 589.6 57.3 102 GJ8 0.06106 0.00117 0.09742 0.00139 0.81984 0.01673 0.03241 0.00255 641.3 40.8 599.2 8.2 608.0 9.3 644.8 50.0 93 GJ9 0.06034 0.00118 0.09786 0.0014 0.81395 0.01682 0.02777 0.00239 615.9 41.5 601.9 8.2 604.7 9.4 553.7 47.0 98 GJ10 0.06043 0.00121 0.09796 0.00139 0.81588 0.01716 0.0341 0.00249 619.1 42.6 602.4 8.2 605.7 9.6 677.8 48.7 97 GJ11 0.06005 0.00126 0.09724 0.00142 0.80513 0.01788 0.03119 0.00247 605.4 44.8 598.2 8.4 599.7 10.1 620.8 48.5 99 GJ12 0.06001 0.00127 0.09795 0.00144 0.81055 0.01807 0.0306 0.00249 604.1 45.0 602.4 8.4 602.8 10.1 609.2 48.9 100 GJ13 0.06031 0.00126 0.09826 0.00141 0.81648 0.01789 0.03196 0.00272 614.6 44.6 604.2 8.3 606.1 10.0 636.0 53.4 98 GJ14 0.06259 0.00125 0.09798 0.0014 0.84499 0.0178 0.02723 0.00251 694.4 42.0 602.6 8.2 621.9 9.8 543.0 49.3 87 GJ15 0.05947 0.00144 0.09857 0.00152 0.80789 0.0202 0.03288 0.00316 584.3 51.8 606.0 8.9 601.3 11.4 653.8 61.9 104 GJ16 0.06123 0.00124 0.09659 0.0014 0.81437 0.01744 0.03103 0.00263 647.2 42.9 594.4 8.2 604.9 9.8 617.6 51.7 92 GJ17 0.05957 0.00128 0.09835 0.00143 0.8068 0.01815 0.03195 0.00299 588.0 46.0 604.7 8.4 600.7 10.2 635.7 58.5 103 GJ Mean 617.0 21 [2σ] 601.4 3.9 [2σ] 604.1 4.7 [2σ] Weighted Av. 95% conf. (1.96σ) GJ Mean (GEMOC) 607.7 4.3 [2σ] 600.7 1.1[2σ] 602.0 1.0 [2σ] Plesovice ples1 0.05380 0.00087 0.05712 0.00078 0.42365 0.00755 0.02023 0.00060 362.4 36.1 358.1 4.8 358.7 5.4 404.8 12.0 99 ples2 0.05358 0.00089 0.05667 0.00078 0.41858 0.00762 0.01974 0.00059 353.2 37.1 355.3 4.8 355.0 5.5 395.0 11.7 101 ples3 0.05260 0.00087 0.05716 0.00079 0.41444 0.00756 0.01839 0.00061 311.7 37.2 358.3 4.8 352.1 5.4 368.4 12.1 115 ples4 0.05319 0.00089 0.05634 0.00078 0.41305 0.00761 0.01801 0.00061 336.8 37.4 353.3 4.8 351.1 5.5 360.7 12.1 105 ples5 0.05440 0.00090 0.05623 0.00078 0.42116 0.00778 0.01874 0.00066 387.6 36.7 352.6 4.8 356.9 5.6 375.2 13.1 91 ples6 0.05344 0.00093 0.05586 0.00077 0.41129 0.00782 0.01804 0.00068 347.5 39.0 350.4 4.7 349.8 5.6 361.4 13.6 101 Ples Mean 350.0 30 [2σ] 354.6 3.8 [2σ) 354.0 4.4 [2σ] Weighted Av. 95% conf. (1.96σ) Ples Mean (Slama et al., 2008) 339.2 0.25 [2σ] 337.1 0.37 [2σ] 337.3 0.11 [2σ]
389 Table 17: U-Pb isotope data from Al Bad Granite Super Suite (abg) zircon grains analysed by LA-ICPMS (Appendix a1). These values have been numerically arranged to highlight the maximum and minimum values. Consequently, the spot numbers are no longer in subsequent experimental time. However, spot numbers 1-10, 11-20 and 21-31 correspond to Block 1 (GJ standards 1-7), Block 2 (GJ standards 6-12) and Block 3 (GJ standards 11-17) respectively (see standard Table 17-continued). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 206Pb/238U 207Pb/235U 208Pb/232Th σ from 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ ±1σ ±1σ ±1σ ±1σ Conc. No. (Ma) (Ma) (Ma) (Ma) mean Al Bad Granite Super Suite (abg)-sample abg179, n=31 Spot17 0.06038 0.00262 0.10262 0.00224 0.85435 0.03693 0.03271 0.00400 617.3 91.0 629.8 13.1 627.0 20.2 650.5 78.3 102 2.48 Spot6 0.05932 0.00261 0.10132 0.00232 0.82819 0.03636 0.02811 0.00216 578.9 92.7 622.1 13.6 612.6 20.2 560.4 42.4 107 1.82 Spot4 0.06090 0.00163 0.09986 0.00181 0.83807 0.02365 0.03560 0.00199 635.8 56.5 613.6 10.6 618.1 13.1 707.0 38.8 97 1.53 Spot20 0.06134 0.00269 0.09959 0.00225 0.84229 0.03703 0.02356 0.00324 651.3 91.4 612.0 13.2 620.4 20.4 470.6 64.0 94 1.11 Spot3 0.06016 0.00126 0.09957 0.00170 0.82547 0.01935 0.03589 0.00203 609.5 44.8 611.9 10.0 611.1 10.8 712.7 39.6 100 1.46 Spot11 0.05976 0.00184 0.09896 0.00195 0.81535 0.02602 0.02757 0.00201 594.6 65.7 608.3 11.4 605.4 14.6 549.6 39.6 102 0.95 Spot21 0.06087 0.00206 0.09886 0.00195 0.82970 0.02885 0.02999 0.00360 634.8 71.2 607.7 11.4 613.4 16.0 597.2 70.7 96 0.90 Spot25 0.06040 0.00328 0.09873 0.00236 0.82228 0.04342 0.03793 0.00827 618.0 113.0 607.0 13.8 609.3 24.2 752.5 161.1 98 0.70 Spot2 0.06372 0.00175 0.09869 0.00181 0.86648 0.02508 0.03435 0.00188 732.2 57.2 606.7 10.6 633.7 13.7 682.6 36.7 83 0.88 Spot5 0.05846 0.00184 0.09825 0.00187 0.79148 0.02567 0.03325 0.00188 547.1 67.4 604.1 11.0 592.0 14.6 661.1 36.7 110 0.61 Spot9 0.06093 0.00212 0.09824 0.00209 0.82505 0.02930 0.02457 0.00232 636.9 73.1 604.1 12.3 610.9 16.3 490.7 45.7 95 0.55 Spot1 0.06323 0.00205 0.09778 0.00190 0.85190 0.02830 0.03526 0.00183 716.0 67.3 601.4 11.2 625.7 15.5 700.4 35.8 84 0.36 Spot7 0.05996 0.00293 0.09756 0.00219 0.80618 0.03862 0.03316 0.00232 602.2 102.3 600.1 12.8 600.3 21.7 659.3 45.4 100 0.21 Spot29 0.06096 0.00333 0.09755 0.00242 0.81991 0.04409 0.02909 0.00578 637.9 113.3 600.0 14.2 608.0 24.6 579.5 113.5 94 0.18 Spot30 0.06142 0.00279 0.09742 0.00218 0.82493 0.03734 0.03138 0.00548 654.0 94.7 599.3 12.8 610.8 20.8 624.5 107.4 92 0.15 Spot10 0.05839 0.00131 0.09715 0.00169 0.78193 0.01911 0.03076 0.00180 544.4 48.6 597.7 9.9 586.6 10.9 612.4 35.2 110 0.03 Spot8 0.05966 0.00116 0.09688 0.00165 0.79664 0.01764 0.03056 0.00169 591.4 41.5 596.1 9.7 594.9 10.0 608.4 33.2 101 -0.13 Spot22 0.06304 0.00311 0.09647 0.00233 0.83842 0.04108 0.02309 0.00341 709.6 101.4 593.7 13.7 618.3 22.7 461.3 67.4 84 -0.27 Spot12 0.05812 0.00162 0.09612 0.00174 0.77023 0.02238 0.02929 0.00182 533.9 60.4 591.6 10.3 579.9 12.8 583.5 35.7 111 -0.56 Spot16 0.06138 0.00195 0.09559 0.00182 0.80894 0.02649 0.02328 0.00247 652.7 66.9 588.5 10.7 601.9 14.9 465.2 48.9 90 -0.83 Spot14 0.05954 0.00189 0.09536 0.00183 0.78269 0.02565 0.02784 0.00261 586.9 67.5 587.2 10.8 587.0 14.6 555.1 51.3 100 -0.95 Spot15 0.06257 0.00259 0.09535 0.00199 0.82246 0.03381 0.03089 0.00369 693.5 85.7 587.1 11.7 609.4 18.8 615.0 72.4 85 -0.88 Spot26 0.06069 0.00279 0.09519 0.00210 0.79656 0.03616 0.03235 0.00582 628.4 96.1 586.2 12.4 594.9 20.4 643.4 113.9 93 -0.90 Spot13 0.06459 0.00256 0.09515 0.00204 0.84731 0.03380 0.02535 0.00261 761.0 81.5 585.9 12.0 623.2 18.6 506.0 51.4 77 -0.96 Spot18 0.06123 0.00247 0.09495 0.00205 0.80158 0.03266 0.02724 0.00361 647.2 84.5 584.7 12.1 597.7 18.4 543.2 71.1 90 -1.05 Spot28 0.06221 0.00376 0.09483 0.00252 0.81323 0.04830 0.02976 0.00688 681.2 124.2 584.0 14.8 604.3 27.1 592.7 135.0 86 -0.90 Spot19 0.06552 0.00327 0.09479 0.00227 0.85637 0.04221 0.02466 0.00402 791.1 101.2 583.8 13.3 628.1 23.1 492.3 79.2 74 -1.02 Spot23 0.06350 0.00373 0.09400 0.00248 0.82290 0.04758 0.02063 0.00370 725.0 119.8 579.2 14.6 609.7 26.5 412.8 73.3 80 -1.25 Spot31 0.06068 0.00300 0.09350 0.00217 0.78221 0.03827 0.03204 0.00627 628.0 103.3 576.2 12.8 586.7 21.8 637.5 122.7 92 -1.66 Spot27 0.06271 0.00312 0.09340 0.00222 0.80747 0.03982 0.02733 0.00480 698.4 102.6 575.6 13.1 601.0 22.4 544.9 94.5 82 -1.66 Spot24 0.06250 0.00379 0.09305 0.00238 0.80172 0.04710 0.03333 0.00832 691.3 124.3 573.5 14.1 597.8 26.6 662.7 162.7 83 -1.70
abg Mean, n=31 U-Pb Concordia (isoptope ratios): Groups seperated based on σ from mean 602.9 5.6 (±1σ) MSWD=0.75
abg Mean, n=31 Weighted Av. (assigned internal errors) 95% conf. 1.96σ: Groups seperated based on σ from 597.4 4.8 [0.81%] MSWD=1.2 mean
390 Table 17 (continued): U-Pb absolute age data for zircon standards analysed by LA-ICPMS (Appendix a1). These standards have recognised age values (see Jackson et al., 2004 and Slama et al, 2008), which are used to tie the unknown zircon values by linear modelling (standards provide error bounds on unknown values). Block 1 (GJ standards 1-7), Block 2 (GJ standards 6-12) and Block 3 (GJ standards 11-17) correspond to absolute age values 1-10, 11-20 and 21-31 respectively (see abg ages Table 17). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 206Pb/238U 207Pb/235U 208Pb/232Th 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ ±1σ ±1σ ±1σ ±1σ Conc. No. (Ma) (Ma) (Ma) (Ma) Al Bad Granite Super Suite (abg)-sample abg179, n=31 GJ GJ1 0.06151 0.00117 0.09510 0.00168 0.80567 0.01823 0.03621 0.00237 657.1 40.4 585.6 9.9 600.0 10.3 719.0 46.3 89 GJ2 0.06030 0.00118 0.09612 0.00170 0.79830 0.01832 0.02811 0.00205 614.3 41.7 591.6 10.0 595.9 10.4 560.3 40.3 96 GJ3 0.06041 0.00119 0.09738 0.00172 0.81028 0.01862 0.03408 0.00242 618.3 41.9 599.0 10.1 602.6 10.4 677.4 47.3 97 GJ4 0.05825 0.00117 0.10070 0.00176 0.80804 0.01873 0.02289 0.00182 538.5 43.9 618.5 10.3 601.4 10.5 457.4 35.9 115 GJ5 0.05960 0.00118 0.10122 0.00177 0.83107 0.01908 0.03564 0.00246 589.1 42.5 621.5 10.4 614.2 10.6 707.9 48.1 105 GJ6 0.06044 0.00166 0.09778 0.00177 0.81473 0.02343 0.02798 0.00279 619.5 58.1 601.4 10.4 605.1 13.1 557.8 54.9 97 GJ7 0.06059 0.00170 0.09819 0.00178 0.82014 0.02397 0.03360 0.00339 624.7 59.2 603.8 10.5 608.1 13.4 668.0 66.2 97 GJ8 0.05869 0.00162 0.09861 0.00180 0.79786 0.02318 0.03141 0.00316 555.8 59.2 606.3 10.6 595.6 13.1 625.1 61.9 109 GJ9 0.06031 0.00170 0.09659 0.00178 0.80299 0.02369 0.02987 0.00304 614.7 59.6 594.4 10.5 598.5 13.3 595.0 59.7 97 GJ10 0.06104 0.00174 0.09713 0.00180 0.81730 0.02442 0.03240 0.00331 640.6 60.1 597.6 10.6 606.5 13.7 644.5 64.9 93 GJ11 0.05867 0.00235 0.09773 0.00205 0.79050 0.03173 0.03197 0.00474 554.9 85.2 601.1 12.0 591.5 18.0 636.1 92.9 108 GJ12 0.06020 0.00248 0.09872 0.00209 0.81939 0.03364 0.02982 0.00464 610.9 86.5 606.9 12.3 607.7 18.8 593.9 91.0 99 GJ13 0.06085 0.00273 0.09887 0.00214 0.82952 0.03672 0.03366 0.00595 634.1 93.9 607.8 12.6 613.3 20.4 669.1 116.4 96 GJ14 0.06090 0.00256 0.09623 0.00206 0.80795 0.03384 0.02703 0.00437 635.7 88.0 592.3 12.1 601.3 19.0 539.2 85.9 93 GJ15 0.06005 0.00277 0.09653 0.00213 0.79925 0.03637 0.03271 0.00597 605.4 96.9 594.1 12.5 596.4 20.5 650.6 116.8 98 GJ16 0.05887 0.00431 0.09900 0.00290 0.80310 0.05660 0.02749 0.00842 562.3 152.0 608.5 17.0 598.6 31.9 548.2 165.7 108 GJ17 0.06058 0.00297 0.09784 0.00227 0.81709 0.03959 0.03278 0.00641 624.2 102.2 601.7 13.3 606.4 22.1 651.9 125.4 96 GJ Mean 607.0 28 [2σ] 601.6 5.3 [2σ] 602.6 6.5 [2σ] Weighted Av. 95% conf. (1.96σ) GJ Mean (GEMOC) 607.7 4.3 [2σ] 600.7 1.1[2σ] 602.0 1.0 [2σ] Plesovice ples1 0.05364 0.00091 0.05432 0.00093 0.40134 0.00839 0.01836 0.00085 355.8 37.9 341.0 5.7 342.6 6.1 367.7 16.8 96 ples2 0.05267 0.00094 0.05463 0.00094 0.39639 0.00852 0.01887 0.00091 314.8 39.9 342.9 5.8 339.0 6.2 377.9 18.1 109 ples3 0.05245 0.00137 0.05500 0.00099 0.39769 0.01104 0.01569 0.00134 305.2 58.2 345.1 6.1 340.0 8.0 314.7 26.6 113 ples4 0.05365 0.00147 0.05416 0.00098 0.40059 0.01152 0.01599 0.00149 356.2 60.5 340.0 6.0 342.1 8.4 320.7 29.6 95 ples5 0.05383 0.00238 0.05325 0.00115 0.39524 0.01724 0.01807 0.00306 363.8 96.0 334.5 7.0 338.2 12.5 362.0 60.7 92 ples6 0.05176 0.00228 0.05369 0.00116 0.38312 0.01668 0.01731 0.00289 274.6 97.8 337.1 7.1 329.3 12.3 346.9 57.4 123 Ples Mean 333.0 43 [2σ] 340.6 5.0 [2σ) 339.9 6.3 [2σ] Weighted Av. 95% conf. (1.96σ) Ples Mean (Slama et al., 2008) 339.2 0.25 [2σ] 337.1 0.37 [2σ] 337.3 0.11 [2σ]
391 Table 18: U-Pb isotope data from Al Hawiyah Suite (hwg) zircon grains analysed by LA-ICPMS (Appendix a1). These values have been numerically arranged to highlight the maximum and minimum values. Consequently, the spot numbers are no longer in subsequent experimental time. However, spot numbers 1-10 , 11-18 and 19-27 correspond to Block 1 (GJ standards 1-7), Block 2 (GJ standards 6-12) and Block 3 (GJ standards 11-17) respectively (see standard Table 18-continued). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 206Pb/238U 207Pb/235U 208Pb/232Th σ from 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ ±1σ ±1σ ±1σ ±1σ Conc. No. (Ma) (Ma) (Ma) (Ma) mean Al Hawiyah Suite (hwg)-sample hwg07, n=27 Spot15 0.06217 0.00077 0.10129 0.00152 0.86824 0.01411 0.03083 0.00042 679.9 26.1 622.0 8.9 634.6 7.7 613.8 8.3 91 3.37 Spot9 0.06217 0.00345 0.09985 0.00254 0.85590 0.04658 0.03611 0.00763 679.9 114.3 613.6 14.9 627.9 25.5 717.0 148.8 90 1.46 Spot1 0.06544 0.00107 0.09901 0.00164 0.89308 0.01765 0.03615 0.00159 788.6 34.1 608.6 9.6 648.0 9.5 717.8 31.0 77 1.74 Spot21 0.06304 0.00078 0.09829 0.00149 0.85408 0.01406 0.03372 0.00045 709.6 26.1 604.4 8.8 626.9 7.7 670.4 8.8 85 1.42 Spot17 0.06321 0.00067 0.09812 0.00145 0.85509 0.01286 0.03383 0.00038 715.2 22.2 603.4 8.5 627.4 7.0 672.4 7.4 84 1.35 Spot2 0.06779 0.00141 0.09795 0.00169 0.91525 0.02127 0.03487 0.00161 862.2 42.7 602.4 9.9 659.8 11.3 692.7 31.5 70 1.06 Spot25 0.06093 0.00060 0.09795 0.00146 0.82281 0.01209 0.02182 0.00021 636.8 21.1 602.4 8.6 609.6 6.7 436.2 4.1 95 1.22 Spot10 0.06174 0.00330 0.09773 0.00246 0.83193 0.04363 0.02690 0.00482 665.1 110.7 601.1 14.5 614.7 24.2 536.5 94.8 90 0.64 Spot18 0.06298 0.00087 0.09773 0.00150 0.84859 0.01478 0.03130 0.00049 707.4 29.2 601.1 8.8 623.9 8.1 622.9 9.6 85 1.05 Spot11 0.06207 0.00345 0.09758 0.00246 0.83493 0.04555 0.03306 0.00712 676.4 114.6 600.2 14.5 616.3 25.2 657.5 139.3 89 0.57 Spot19 0.06299 0.00069 0.09729 0.00148 0.84448 0.01322 0.03142 0.00039 708.0 23.3 598.5 8.7 621.6 7.3 625.2 7.7 85 0.76 Spot24 0.06132 0.00065 0.09705 0.00141 0.82039 0.01208 0.03029 0.00034 650.3 22.7 597.1 8.3 608.3 6.7 603.2 6.6 92 0.63 Spot26 0.05919 0.00087 0.09659 0.00141 0.78828 0.01369 0.03032 0.00049 574.2 31.5 594.4 8.3 590.2 7.8 603.8 9.5 104 0.30 Spot8 0.06326 0.00183 0.09638 0.00186 0.84056 0.02572 0.04385 0.00458 717.0 60.3 593.2 10.9 619.5 14.2 867.4 88.6 83 0.12 Spot20 0.06087 0.00062 0.09629 0.00144 0.80787 0.01206 0.02877 0.00029 634.5 21.6 592.6 8.5 601.3 6.8 573.3 5.7 93 0.08 Spot27 0.06513 0.00070 0.09616 0.00137 0.86339 0.01256 0.03388 0.00040 778.4 22.5 591.9 8.0 632.0 6.8 673.5 7.7 76 0.00 Spot6 0.06065 0.00118 0.09564 0.00167 0.79971 0.01844 0.03487 0.00231 626.7 41.3 588.8 9.8 596.7 10.4 692.9 45.2 94 -0.32 Spot3 0.06197 0.00109 0.09547 0.00157 0.81554 0.01684 0.03411 0.00145 673.0 37.3 587.8 9.2 605.6 9.4 677.9 28.4 87 -0.45 Spot23 0.06178 0.00061 0.09532 0.00138 0.81186 0.01164 0.02770 0.00027 666.6 21.1 586.9 8.1 603.5 6.5 552.3 5.3 88 -0.62 Spot13 0.05987 0.00069 0.09505 0.00153 0.78475 0.01309 0.02840 0.00035 598.9 24.8 585.3 9.0 588.2 7.5 566.1 6.9 98 -0.74 Spot16 0.06580 0.00089 0.09495 0.00143 0.86132 0.01454 0.03567 0.00053 800.1 28.0 584.7 8.4 630.8 7.9 708.5 10.3 73 -0.86 Spot7 0.05977 0.00170 0.09457 0.00186 0.77949 0.02443 0.03309 0.00349 594.9 60.8 582.5 10.9 585.2 13.9 658.0 68.3 98 -0.86 Spot4 0.06169 0.00172 0.09423 0.00181 0.80114 0.02379 0.02737 0.00171 663.5 58.7 580.5 10.6 597.5 13.4 545.7 33.6 87 -1.07 Spot14 0.06753 0.00067 0.09391 0.00139 0.87441 0.01279 0.02082 0.00021 854.2 20.5 578.6 8.2 638.0 6.9 416.6 4.1 68 -1.63 Spot12 0.06193 0.00062 0.09337 0.00135 0.79725 0.01146 0.02886 0.00029 671.7 21.3 575.5 8.0 595.3 6.5 575.1 5.6 86 -2.06 Spot5 0.06224 0.00180 0.09180 0.00176 0.78780 0.02404 0.02987 0.00181 682.2 60.7 566.2 10.4 589.9 13.7 595.0 35.6 83 -2.48 Spot22 0.06623 0.00081 0.09178 0.00131 0.83731 0.01287 0.04076 0.00068 813.6 25.3 566.0 7.7 617.7 7.1 807.5 13.2 70 -3.35
hwg Mean, n=27 U-Pb Concordia (isoptope ratios): Groups seperated based on σ from mean 594.9 8.7 (±1σ) MSWD=2.1
hwg Mean, n=27 Weighted Av. (assigned internal errors) 95% conf. 1.96σ: Groups seperated based on σ 591.9 5.2 [0.89%] MSWD=2.1 from mean
392 Table 18 (continued): U-Pb absolute age data for zircon standards analysed by LA-ICPMS (Appendix a1). These standards have recognised age values (see Jackson et al., 2004 and Slama et al, 2008), which are used to tie the unknown zircon values by linear modelling (standards provide error bounds on unknown values). Block 1 (GJ standards 1-7), Block 2 (GJ standards 6-12) and Block 3 (GJ standards 11-17) correspond to absolute age values 1-10, 11-18 and 19-27 respectively (see hwg ages Table 18). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 206Pb/238U 207Pb/235U 208Pb/232Th 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ ±1σ ±1σ ±1σ ±1σ Conc. No. (Ma) (Ma) (Ma) (Ma) Al Hawiyah Suite (hwg)-sample hwg07, n=27 GJ GJ1 0.05897 0.00141 0.09431 0.00158 0.76572 0.01934 0.02414 0.00238 566.0 51.4 581.0 9.3 577.3 11.1 482.1 47.0 103 GJ2 0.06163 0.00100 0.09270 0.00147 0.78691 0.01499 0.02631 0.00135 661.4 34.3 571.5 8.7 589.4 8.5 524.8 26.6 86 GJ3 0.05931 0.00098 0.09649 0.00154 0.78830 0.01522 0.02941 0.00151 578.6 35.3 593.8 9.1 590.2 8.6 585.9 29.6 103 GJ4 0.06078 0.00101 0.09879 0.00159 0.82715 0.01613 0.03396 0.00171 631.5 35.4 607.3 9.3 612.0 9.0 674.9 33.5 96 GJ5 0.06034 0.00104 0.09863 0.00161 0.82000 0.01654 0.02848 0.00160 615.7 36.8 606.4 9.5 608.1 9.2 567.6 31.4 98 GJ6 0.05933 0.00104 0.09855 0.00162 0.80576 0.01644 0.02909 0.00163 579.3 37.5 605.9 9.5 600.1 9.2 579.6 32.0 105 GJ7 0.06065 0.00135 0.10136 0.00177 0.84742 0.02076 0.03697 0.00284 626.9 47.3 622.4 10.4 623.2 11.4 733.7 55.4 99 GJ8 0.06149 0.00126 0.09317 0.00161 0.78970 0.01821 0.03566 0.00232 656.4 43.3 574.2 9.5 591.0 10.3 708.2 45.4 87 GJ9 0.05978 0.00107 0.09482 0.00155 0.78135 0.01628 0.03100 0.00183 595.1 39.0 584.0 9.2 586.3 9.3 617.0 35.8 98 GJ10 0.05974 0.00168 0.09722 0.00184 0.80057 0.02382 0.03035 0.00338 594.1 59.8 598.1 10.8 597.2 13.4 604.3 66.2 101 GJ11 0.06044 0.00171 0.09852 0.00187 0.82084 0.02460 0.03106 0.00347 619.4 60.0 605.7 11.0 608.5 13.7 618.3 68.1 98 GJ12 0.05935 0.00170 0.09807 0.00186 0.80225 0.02427 0.03117 0.00352 579.8 61.2 603.1 10.9 598.1 13.7 620.4 68.9 104 GJ13 0.06137 0.00180 0.09626 0.00184 0.81439 0.02506 0.03174 0.00363 652.4 61.7 592.4 10.8 604.9 14.0 631.6 71.2 91 GJ14 0.06023 0.00192 0.09752 0.00189 0.80970 0.02667 0.03009 0.00383 611.9 67.6 599.9 11.1 602.3 15.0 599.3 75.2 98 GJ15 0.06053 0.00207 0.09810 0.00198 0.81862 0.02880 0.03016 0.00370 622.4 72.3 603.3 11.6 607.3 16.1 600.5 72.7 97 GJ16 0.05958 0.00209 0.09756 0.00199 0.80138 0.02882 0.03161 0.00394 588.5 74.5 600.1 11.7 597.6 16.2 629.0 77.2 102 GJ17 0.06029 0.00090 0.09761 0.00143 0.81129 0.01422 0.02967 0.00141 614.0 31.8 600.4 8.4 603.2 8.0 591.0 27.7 98 GJ Mean 613.0 21 [2σ] 596.0 6.6 [2σ] 598.9 5.1 [2σ] Weighted Av. 95% conf. (1.96σ) GJ Mean (GEMOC) 607.7 4.3 [2σ] 600.7 1.1[2σ] 602.0 1.0 [2σ] Plesovice ples1 0.05346 0.00089 0.05436 0.00087 0.40033 0.00783 0.01740 0.00075 348.3 37.1 341.2 5.3 341.9 5.7 348.6 14.8 98 ples2 0.05321 0.00084 0.05360 0.00086 0.39295 0.00748 0.01640 0.00068 337.8 35.4 336.6 5.3 336.5 5.5 328.7 13.6 100 ples3 0.05290 0.00098 0.05443 0.00092 0.39694 0.00857 0.01509 0.00081 324.5 41.5 341.7 5.6 339.4 6.2 302.7 16.1 105 ples4 0.05330 0.00147 0.05504 0.00103 0.40440 0.01189 0.01792 0.00187 341.6 61.5 345.4 6.3 344.8 8.6 359.0 37.1 101 ples5 0.05349 0.00148 0.05538 0.00104 0.40839 0.01204 0.01741 0.00181 349.5 61.6 347.5 6.4 347.7 8.7 348.9 36.0 99 ples6 0.05308 0.00083 0.05448 0.00078 0.39858 0.00715 0.01755 0.00063 332.0 35.0 342.0 4.8 340.6 5.2 351.6 12.5 103 Ples Mean 338.0 40 [2σ] 341.9 4.4 [2σ) 340.7 5.0 [2σ] Weighted Av. 95% conf. (1.96σ) Ples Mean (Slama et al., 2008) 339.2 0.25 [2σ] 337.1 0.37 [2σ] 337.3 0.11 [2σ]
393 Table 19: U-Pb isotope data from Mardabah Complex (mr) zircon grains analysed by LA-ICPMS (Appendix a1). These values have been numerically arranged to highlight the maximum and minimum values. Consequently, the spot numbers are no longer in subsequent experimental time. However, spot numbers 1-8 and 9-17 correspond to Block 1 (GJ standards 1-7) and Block 2 (GJ standards 6-12) respectively (see standard Table 19-continued). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ 207Pb/206Pb ±1σ 206Pb/238U ±1σ 207Pb/235U ±1σ 208Pb/232Th ±1σ Conc. σ from No. (Ma) (Ma) (Ma) (Ma) mean Mardabah Complex (mr)-sample mr191, n=17 Spot3 0.05759 0.00087 0.08771 0.00134 0.69621 0.01238 0.02783 0.00117 513.9 33.0 542.0 7.9 536.5 7.4 554.9 23.1 105 2.07 Spot5 0.05923 0.00097 0.08738 0.00132 0.71335 0.01322 0.02747 0.00124 575.4 35.2 540.0 7.9 546.7 7.8 547.7 24.5 94 1.83 Spot2 0.05638 0.00116 0.08651 0.00139 0.67222 0.01505 0.02712 0.00115 466.6 45.2 534.8 8.3 522.1 9.1 540.9 22.6 115 1.11 Spot4 0.05728 0.00096 0.08604 0.00131 0.67931 0.01288 0.02682 0.00119 502.0 36.4 532.1 7.8 526.4 7.8 534.9 23.5 106 0.83 Spot6 0.05604 0.00146 0.08586 0.00145 0.66337 0.01799 0.02495 0.00174 453.6 56.8 531.0 8.6 516.7 11.0 498.1 34.4 117 0.63 Spot14 0.05704 0.00149 0.08553 0.00144 0.67257 0.01826 0.02346 0.00186 492.3 57.2 529.1 8.5 522.3 11.1 468.7 36.7 107 0.41 Spot1 0.06366 0.00226 0.08513 0.00184 0.74601 0.02722 0.01740 0.00161 730.4 73.5 526.7 11.0 565.9 15.8 348.7 31.9 72 0.10 Spot13 0.05684 0.00166 0.08475 0.00147 0.66420 0.01982 0.02391 0.00189 484.8 63.9 524.4 8.7 517.2 12.1 477.5 37.4 108 -0.14 Spot9 0.05517 0.00166 0.08462 0.00146 0.64363 0.01958 0.02519 0.00222 418.9 65.1 523.7 8.7 504.5 12.1 502.9 43.7 125 -0.22 Spot12 0.05608 0.00142 0.08450 0.00141 0.65333 0.01728 0.02443 0.00192 455.2 55.3 522.9 8.4 510.5 10.6 487.8 37.9 115 -0.33 Spot16 0.05690 0.00153 0.08450 0.00143 0.66290 0.01842 0.02259 0.00186 487.2 58.9 522.9 8.5 516.4 11.3 451.5 36.8 107 -0.32 Spot17 0.05629 0.00164 0.08426 0.00146 0.65391 0.01953 0.02204 0.00182 463.2 63.9 521.5 8.7 510.9 12.0 440.7 36.0 113 -0.47 Spot11 0.05721 0.00162 0.08417 0.00144 0.66389 0.01930 0.02591 0.00204 499.2 61.8 520.9 8.6 517.0 11.8 517.0 40.2 104 -0.55 Spot10 0.05743 0.00139 0.08383 0.00138 0.66367 0.01693 0.02658 0.00203 507.5 52.9 518.9 8.2 516.9 10.3 530.2 39.9 102 -0.82 Spot7 0.05684 0.00150 0.08315 0.00138 0.65161 0.01772 0.02556 0.00209 484.8 57.1 514.9 8.2 509.5 10.9 510.1 41.2 106 -1.30 Spot15 0.05741 0.00161 0.08301 0.00143 0.65704 0.01897 0.02401 0.00194 507.0 61.1 514.1 8.5 512.8 11.6 479.6 38.3 101 -1.36 Spot8 0.05860 0.00187 0.08230 0.00145 0.66490 0.02136 0.02490 0.00229 552.1 68.3 509.9 8.7 517.6 13.0 497.2 45.2 92 -1.82
mr Mean, n=17 U-Pb Concordia (isoptope ratios): Groups seperated based on σ from mean 525.7 4.3 (±1σ) MSWD=1.2
Weighted Av. (assigned internal errors) 95% conf. 1.96σ: Groups seperated based on σ mr Mean, n=17 525.6 4.7 [0.89%] MSWD=0.76 from mean
394 Table 19 (continued): U-Pb absolute age data for zircon standards analysed by LA-ICPMS (Appendix a1). These standards have recognised age values (see Jackson et al., 2004 and Slama et al, 2008), which are used to tie the unknown zircon values by linear modelling (standards provide error bounds on unknown values). Block 1 (GJ standards 1-7) and Block 2 (GJ standards 6-12) correspond to absolute age values 1-8 and 9-17 respectively (see mr ages Table 19). Values were processed using Glitter (Van Achterbergh et al., 2001) and Isoplot software (Ludwig, 2000).
Analysis 207Pb/206Pb 206Pb/238U 207Pb/235U 208Pb/232Th 207Pb/206Pb 1σ 206Pb/238U 1σ 207Pb/235U 1σ 208Pb/232Th 1σ ±1σ ±1σ ±1σ ±1σ Conc. No. (Ma) (Ma) (Ma) (Ma) Mardabah Complex (mr)-sample mr191, n=17 GJ GJ1 0.06023 0.00091 0.09803 0.00171 0.81451 0.01638 0.02960 0.00141 611.9 32.5 602.8 10.0 605.0 9.2 589.5 27.6 99 GJ2 0.05931 0.00096 0.09656 0.00168 0.79000 0.01633 0.02937 0.00154 578.5 34.7 594.2 9.9 591.2 9.3 585.0 30.3 103 GJ3 0.05907 0.00098 0.09638 0.00166 0.78527 0.01634 0.03498 0.00183 569.6 35.7 593.2 9.8 588.5 9.3 695.0 35.7 104 GJ4 0.06069 0.00101 0.09731 0.00167 0.81450 0.01688 0.02999 0.00165 628.4 35.6 598.6 9.8 605.0 9.5 597.2 32.5 95 GJ5 0.05994 0.00122 0.09792 0.00156 0.80920 0.01802 0.03014 0.00221 601.4 43.5 602.2 9.1 602.0 10.1 600.2 43.4 100 GJ6 0.06036 0.00128 0.09793 0.00156 0.81503 0.01870 0.03202 0.00247 616.6 45.3 602.3 9.2 605.3 10.5 637.0 48.4 98 GJ7 0.05998 0.00130 0.09818 0.00157 0.81183 0.01893 0.03002 0.00239 602.8 46.4 603.7 9.2 603.5 10.6 597.9 46.8 100 GJ8 0.06018 0.00137 0.09666 0.00158 0.80191 0.01946 0.02957 0.00246 609.9 48.4 594.8 9.3 597.9 11.0 589.0 48.3 98 GJ9 0.06032 0.00141 0.09754 0.00159 0.81110 0.02013 0.03253 0.00279 614.9 49.9 600.0 9.4 603.1 11.3 647.0 54.6 98 GJ10 0.06029 0.00166 0.09765 0.00165 0.81169 0.02298 0.03068 0.00308 614.1 58.5 600.6 9.7 603.4 12.9 610.8 60.4 98 GJ11 0.05983 0.00162 0.09797 0.00166 0.80804 0.02250 0.03111 0.00304 597.3 57.5 602.5 9.7 601.4 12.6 619.2 59.6 101 GJ12 0.05993 0.00151 0.09784 0.00160 0.80777 0.02193 0.03022 0.00287 604.1 44.3 599.5 9.6 600.6 10.6 615.3 44.3 100 GJ Mean 603.0 24 [2σ] 599.6 5.4 [2σ] 600.2 5.9 [2σ] Weighted Av. 95% conf. (1.96σ) GJ Mean (GEMOC) 607.7 4.3 [2σ] 600.7 1.1[2σ] 602.0 1.0 [2σ] Plesovice ples1 0.05372 0.00075 0.05522 0.00092 0.40912 0.00764 0.01701 0.00053 359.4 31.1 346.5 5.6 348.2 5.5 340.8 10.6 96 ples2 0.05264 0.00115 0.05610 0.00089 0.40711 0.00949 0.01788 0.00136 313.4 48.8 351.8 5.4 346.8 6.9 358.3 27.1 112 ples3 0.05254 0.00115 0.05615 0.00089 0.40676 0.00951 0.01753 0.00133 309.1 48.9 352.2 5.5 346.5 6.9 351.3 26.5 114 ples4 0.05199 0.00112 0.05601 0.00090 0.40698 0.00470 0.01733 0.00130 327.3 42.9 350.2 5.5 347.2 6.4 350.1 21.4 101 Ples Mean 335.0 40 [2σ] 350.2 5.4 [2σ) 347.3 6.2 [2σ] Weighted Av. 95% conf. (1.96σ) Ples Mean (Slama et al., 2008) 339.2 0.25 [2σ] 337.1 0.37 [2σ] 337.3 0.11 [2σ]
395 Appendix 3: Zircon Catholuminescence Images
396 Island Arc Magmatism (~950-750 Ma) Pre-Arabian Shield Assembly
397 Figure A3.1: Catholuminescence images of zircon grains from the Makkah Suite (dm) with corresponding 238U-206Pb absolute age data and calculated ɛHf data (see Appendices 2 and 4, Table 1). The images have been subdivided into 3 groups based on morphology, geochemistry and age (see Chapter 6). Analyses labelled ‘REE’ correspond to trace element investigation discussed in Chapter 5. The numbers ‘1’ and ‘2’ refer to the photographic scale located in the middle of the image.
398 Syncollisional Magmatism (~736-636 Ma) Arabian Shield Microplate Accretion and Suture Formation
399 Figure A3.2: Catholuminescence images of zircon grains from the Shufayyah Complex (su) with corresponding 238U-206Pb absolute age data and calculated ɛHf data (see Appendices 2 and 4, Table 2). The images have been subdivided into 3 groups based on morphology, geochemistry and age (see Chapter 6). Analyses labelled ‘REE’ correspond to trace element investigation discussed in Chapter 5. The numbers ‘1’ and ‘2’ refer to the photographic scale located in the middle of the image.
400 Figure A3.3: Catholuminescence images of zircon grains from the Jar-Salajah Complex (js) with corresponding 238U-206Pb absolute age data and calculated ɛHf data (see Appendices 2 and 4, Table 3). The images have been subdivided into 3 groups based on morphology, geochemistry and age (see Chapter 6). Analyses labelled ‘REE’ correspond to trace element investigation discussed in Chapter 5. The numbers ‘1’, ‘2’ and ‘3’ refer to the photographic scale located in the middle of the image.
401 Figure A3.4: Catholuminescence images of zircon grains from the Subh Suite (sf) with corresponding 238U-206Pb absolute age data and calculated ɛHf data (see Appendices 2 and 4, Table 4). Analyses labelled ‘REE’ correspond to trace element investigation discussed in Chapter 5. The numbers ‘1’and ‘2’ refer to the photographic scale located in the middle of the image.
402 Post-Orogenic Magmatism (~636-600 Ma) Post-Arabian Shield Terrane Accretion
403 Figure A3.5: Catholuminescence images of zircon grains from the Kawr Suite (kw) with corresponding 238U-206Pb absolute age data and calculated ɛHf data (see Appendices 2 and 4, Table 5). The images have been subdivided into 3 groups based on morphology, geochemistry and age (see Chapter 6). Analyses labelled ‘REE’ correspond to trace element investigation discussed in Chapter 5. The numbers ‘1’, ‘2’ and ‘3’ refer to the photographic scale located in the middle of the image.
404 Figure A3.6: Catholuminescence images of zircon grains from the Al Hafoor Suite (ao) with corresponding 238U-206Pb absolute age data and calculated ɛHf data (see Appendices 2 and 4, Table 6). Analyses labelled ‘REE’ correspond to trace element investigation discussed in Chapter 5. The number ‘1’refers to the photographic scale located in the middle of the image.
405 Figure A3.7: Catholuminescence images of zircon grains from the Najirah Granite (nr) with corresponding 238U-206Pb absolute age data and calculated ɛHf data (see Appendices 2 and 4, Table 7). The images have been subdivided into 3 groups based on morphology, geochemistry and age (see Chapter 6). Analyses labelled ‘REE’ correspond to trace element investigation discussed in Chapter 5. The number ‘1’refers to the photographic scale located in the middle of the image.
406 Figure A3.8: Catholuminescence images of zircon grains from the Wadbah Suite (wb) with corresponding 238U-206Pb absolute age data and calculated ɛHf data (see Appendices 2 and 4, Table 8). The images have been subdivided into 3 groups based on morphology, geochemistry and age (see Chapter 6). Analyses labelled ‘REE’ correspond to trace element investigation discussed in Chapter 5. The numbers ‘1’, ‘2’ and ‘3’ refer to the photographic scale located in the middle of the image.
407 Figure A3.9: Catholuminescence images of zircon grains from the Ibn Hashbal Suite (ih) with corresponding 238U-206Pb absolute age data and calculated ɛHf data (see Appendices 2 and 4, Table 9). Analyses labelled ‘REE’ correspond to trace element investigation discussed in Chapter 5. The number ‘1’refers to the photographic scale located in the middle of the image.
408 Figure A3.10: Catholuminescence images of zircon grains from the Ar Ruwaydah Suite (ku) with corresponding 238U-206Pb absolute age data and calculated ɛHf data (see Appendices 2 and 4, Table 10). Analyses labelled ‘REE’ correspond to trace element investigation discussed in Chapter 5. The number ‘1’refers to the photographic scale located in the middle of the image.
409 Figure A3.11: Catholuminescence images of zircon grains from the Haml Suite (hla) with corresponding 238U-206Pb absolute age data and calculated ɛHf data (see Appendices 2 and 4, Table 11). Analyses labelled ‘REE’ correspond to trace element investigation discussed in Chapter 5. The number ‘1’refers to the photographic scale located in the middle of the image.
410 Figure A3.12: Catholuminescence images of zircon grains from the Kawr Suite (kw) with corresponding 238U-206Pb absolute age data and calculated ɛHf data (see Appendices 2 and 4, Table 12). Analyses labelled ‘REE’ correspond to trace element investigation discussed in Chapter 5. The numbers ‘1’and ‘2’ refer to the photographic scale located in the middle of the image.
411 Figure A3.13: Catholuminescence images of zircon grains from the Idah Suite (id) with corresponding 238U-206Pb absolute age data and calculated ɛHf data (see Appendices 2 and 4, Table 13). Analyses labelled ‘REE’ correspond to trace element investigation discussed in Chapter 5. The number ‘1’refers to the photographic scale located in the middle of the image.
412 Figure A3.14: Catholuminescence images of zircon grains from the Al Khushaymiyah Suite (ky) with corresponding 238U-206Pb absolute age data and calculated ɛHf data (see Appendices 2 and 4, Table 14). Analyses labelled ‘REE’ correspond to trace element investigation discussed in Chapter 5. The numbers ‘1’and ‘2’ refer to the photographic scale located in the middle of the image.
413 Anorogenic Magmatism (<600 Ma) Post-Arabian Shield Terrane Accretion
414 Figure A3.15: Catholuminescence images of zircon grains from the Malik Granite (kg) with corresponding 238U-206Pb absolute age data and calculated ɛHf data (see Appendices 2 and 4, Table 15). Analyses labelled ‘REE’ correspond to trace element investigation discussed in Chapter 5. The number ‘1’refers to the photographic scale located in the middle of the image.
415 Figure A3.16: Catholuminescence images of zircon grains from the Admar Suite (ad) with corresponding 238U-206Pb absolute age data and calculated ɛHf data (see Appendices 2 and 4, Table 16). Analyses labelled ‘REE’ correspond to trace element investigation discussed in Chapter 5. The numbers ‘1’and ‘2’ refer to the photographic scale located in the middle of the image.
416 Figure A3.17: Catholuminescence images of zircon grains from the Al Bad Granite Super Suite (abg) with corresponding 238U-206Pb absolute age data and calculated ɛHf data (see Appendices 2 and 4, Table 17). Analyses labelled ‘REE’ correspond to trace element investigation discussed in Chapter 5. The numbers ‘1’, ‘2’ and ‘3’ refer to the photographic scale located in the middle of the image.
417 Figure A3.18: Catholuminescence images of zircon grains from the Al Hawiyah Suite (hwg) with corresponding 238U-206Pb absolute age data and calculated ɛHf data (see Appendices 2 and 4, Table 18). Analyses labelled ‘REE’ correspond to trace element investigation discussed in Chapter 5.The number ‘1’refers to the photographic scale located in the middle of the image.
418 Figure A3.19: Catholuminescence images of zircon grains from the Mardabah Complex (mr) with corresponding 238U-206Pb absolute age data and calculated ɛHf data (see Appendices 2 and 4, Table 19). Analyses labelled ‘REE’ correspond to trace element investigation discussed in Chapter 5. The number ‘1’refers to the photographic scale located in the middle of the image.
419 Appendix 4: Zircon Hafnium Isotope Data
420 Island Arc Magmatism (~950-750Ma) Pre-Arabian Shield Assembly
421 Table 1: Lu-Hf isotope data for zircons from the Makkah Suite (dm) analysed by Multicollector-ICPMS. Raw values were processed using HfTrax software (Payne, 2010). Each spot represents a mean value created from the number of values analysed. Standard values for MudTank (Woodhead and Hergt, 2005) and Plesovice (Slama et al., 2008) were used to analyse the precision of the Multicollector. Raw 176Lu/177Hf values were used to calculate 176Hf/177Hf model values based on the 176Lu decay constant (1.87x10-11) after Scherer et al. (2001). The 176Lu decay constant and 206Pb/238U absolute age are used to calculate model ages TDM and TDMcrust with an average crustal composition of 0.015 (Griffin et al., 2002).
206Pb/238U 176Hf/177Hf TDM TDM 176Hf/177Hf 176Hf/177Hf Analysis No. 176Hf/177Hf 2σ 176Lu/177Hf 2σ 176Yb/177Hf 2σ 178Hf/177Hf 2σ No. Values ɛHf (T) 2σ (Ma) (T) (Ga) (Ga) of CHUR (T) of DM (T) Makkah Suite (dm)-sample dm01a Hf Spot1 0.282630 0.000059 0.005112 0.000165 0.208789 0.006519 1.467182 0.000093 64 of 64 853.5 0.282548 10.94 2.07 0.99 1.05 0.282239 0.282635 Hf Spot2 0.282530 0.000031 0.001106 0.000109 0.043560 0.004435 1.467223 0.000081 67 of 67 832.6 0.282513 9.23 1.09 1.03 1.14 0.282252 0.282650 Hf Spot3 0.282512 0.000028 0.000338 0.000021 0.011129 0.001082 1.467395 0.000106 56 of 56 847.4 0.282507 9.34 0.98 1.03 1.14 0.282243 0.282639 Hf Spot4 0.282520 0.000039 0.002107 0.000101 0.082391 0.003890 1.467280 0.000104 60 of 60 841.6 0.282487 8.51 1.35 1.07 1.19 0.282247 0.282644 Hf Spot5 0.282550 0.000031 0.000661 0.000093 0.025658 0.003658 1.467240 0.000068 62 of 62 843.6 0.282540 10.43 1.07 0.99 1.07 0.282246 0.282642 Hf Spot6 0.282548 0.000036 0.002326 0.000063 0.096543 0.003002 1.467276 0.000074 89 of 89 853.6 0.282511 9.63 1.26 1.03 1.13 0.282239 0.282635 Hf Spot7 0.282600 0.000172 0.001510 0.000060 0.064429 0.002947 1.467418 0.000498 106 of 106 847.4 0.282576 11.80 6.02 0.94 0.99 0.282243 0.282639 Hf Spot8 0.282703 0.000166 0.000557 0.000051 0.020903 0.001845 1.467662 0.000700 63 of 63 845.4 0.282694 15.93 5.82 0.77 0.73 0.282244 0.282641 Hf Spot9 0.282500 0.000186 0.000604 0.000064 0.022570 0.002868 1.466355 0.000512 78 of 78 855.9 0.282490 8.93 6.52 1.05 1.17 0.282238 0.282633 Hf Spot10 0.282578 0.000194 0.003748 0.000252 0.127763 0.009675 1.467172 0.000548 109 of 110 843.9 0.282519 9.69 6.80 1.03 1.12 0.282245 0.282642 Hf Spot11 0.282542 0.000035 0.002787 0.000128 0.114442 0.005378 1.467276 0.000073 100 of 100 833.4 0.282498 8.72 1.24 1.06 1.17 0.282252 0.282649 Hf Spot12 0.282516 0.000032 0.001273 0.000069 0.044563 0.003875 1.467309 0.000080 74 of 75 834.7 0.282496 8.68 1.13 1.05 1.17 0.282251 0.282649 Hf Spot13 0.282542 0.000031 0.001701 0.000111 0.066937 0.005015 1.467289 0.000074 107 of 107 845.1 0.282515 9.60 1.07 1.02 1.12 0.282245 0.282641 Hf Spot14 0.282551 0.000046 0.003949 0.000193 0.161564 0.007856 1.467287 0.000075 93 of 93 834.2 0.282489 8.43 1.63 1.08 1.19 0.282251 0.282649 Hf Spot15 0.282570 0.000047 0.004010 0.000242 0.165466 0.007794 1.467286 0.000075 81 of 81 873.3 0.282505 9.84 1.66 1.05 1.13 0.282227 0.282620 Hf Spot16 0.282545 0.000057 0.002293 0.000150 0.095282 0.004194 1.467290 0.000139 41 of 41 876.9 0.282507 10.01 2.00 1.04 1.12 0.282225 0.282618 Hf Spot17 0.282549 0.000038 0.001852 0.000185 0.068986 0.007252 1.467276 0.000076 111 of 111 831.3 0.282520 9.44 1.34 1.02 1.12 0.282253 0.282651 Hf Spot18 0.282530 0.000028 0.000511 0.000041 0.018039 0.001567 1.467291 0.000061 94 of 94 869.1 0.282522 10.36 0.97 1.01 1.10 0.282229 0.282624 Hf Spot19 0.282544 0.000033 0.002237 0.000093 0.096314 0.003608 1.467273 0.000075 105 of 105 867.7 0.282508 9.83 1.15 1.04 1.13 0.282230 0.282625
dm average 0.282556 0.000068 0.002036 0.000115 0.080807 0.004551 1.467252 0.000185 849.0 0.282523 9.97 2.38 1.01 1.10 0.282242 0.282638
MudTank 159 0.282517 0.000023 0.000026 2.5E-07 0.001421 0.000036 1.467215 0.000145 109 of 110
MT. Std. 0.282507 0.000006
Plesovice 176 0.282472 0.000001 0.000122 0.000074 0.007517 0.000734 1.467313 0.000115 100 of 100 Plesovice 177 0.282472 0.000026 0.000105 0.000001 0.000130 0.000130 1.467268 0.000120 107 of 108 Ples. Std. 0.282482 0.000013
422 Syncollisional Magmatism (~736-636 Ma) Arabian Shield Microplate Accretion and Suture Formation
423 Table 2: Lu-Hf isotope data for zircons from the Shufayyah Complex (su) analysed by Multicollector-ICPMS. Raw values were processed using HfTrax software (Payne, 2010). Each spot represents a mean value created from the number of values analysed. Standard values for MudTank (Woodhead and Hergt, 2005) and Plesovice (Slama et al., 2008) were used to analyse the precision of the Multicollector. Raw 176Lu/177Hf values were used to calculate 176Hf/177Hf model values based on the 176Lu decay constant (1.87x10-11) after Scherer et al. (2001). The 176Lu decay constant and 206Pb/238U absolute age are used to calculate model ages TDM and TDMcrust with an average crustal composition of 0.015 (Griffin et al., 2002).
206Pb/238U 176Hf/177Hf TDM TDM 176Hf/177Hf 176Hf/177Hf Analysis No. 176Hf/177Hf 2σ 176Lu/177Hf 2σ 176Yb/177Hf 2σ 178Hf/177Hf 2σ No. Values ɛHf (T) 2σ (Ma) (T) (Ga) (Ga) of CHUR (T) of DM (T) Shufayyah Complex (su)-sample su215 Hf Spot1 0.282625 0.000028 0.001070 0.000038 0.047237 0.001126 1.467314 0.000083 108 of 108 704.5 0.282611 9.85 1.0 0.89 1.00 0.282333 0.282743 Hf Spot2 0.282625 0.000040 0.001462 0.000104 0.057867 0.002616 1.467351 0.000084 76 of 77 724 0.282605 10.06 1.4 0.90 1.00 0.282321 0.282729 Hf Spot3 0.282632 0.000029 0.000841 0.000037 0.038873 0.001208 1.467280 0.000111 91 of 91 731.1 0.282620 10.77 1.0 0.88 0.96 0.282316 0.282724 Hf Spot4 0.282636 0.000074 0.001449 0.000065 0.056195 0.001804 1.467364 0.000207 38 of 38 709.9 0.282616 10.16 2.6 0.88 0.98 0.282330 0.282739 Hf Spot5 0.282604 0.000056 0.001239 0.000008 0.046036 0.001586 1.467257 0.000172 21 of 21 717 0.282588 9.30 2.0 0.92 1.04 0.282325 0.282734 Hf Spot6 0.282667 0.000034 0.001044 0.000038 0.045990 0.001334 1.467270 0.000120 67 of 67 715.7 0.282653 11.58 1.2 0.83 0.90 0.282326 0.282735 Hf Spot7 0.282661 0.000042 0.001241 0.000038 0.056092 0.001601 1.467230 0.000109 67 of 67 713.5 0.282645 11.24 1.5 0.84 0.92 0.282327 0.282737 Hf Spot8 0.282637 0.000036 0.000839 0.000018 0.039596 0.001355 1.467287 0.000114 57 of 57 714 0.282626 10.59 1.3 0.87 0.96 0.282327 0.282736 Hf Spot9 0.282650 0.000035 0.001145 0.000067 0.050483 0.002377 1.467215 0.000085 85 of 85 694.9 0.282635 10.50 1.2 0.86 0.95 0.282339 0.282750 Hf Spot10 0.282658 0.000039 0.001294 0.000143 0.048572 0.003510 1.467367 0.000107 73 of 74 699.1 0.282641 10.80 1.4 0.85 0.94 0.282336 0.282747 Hf Spot11 0.282588 0.000035 0.001169 0.000060 0.049487 0.001028 1.467382 0.000120 81 of 81 730.3 0.282572 9.05 1.2 0.94 1.07 0.282317 0.282724 Hf Spot12 0.282636 0.000030 0.001245 0.000064 0.055303 0.002537 1.467293 0.000132 81 of 82 719.1 0.282619 10.47 1.1 0.88 0.97 0.282324 0.282733 Hf Spot13 0.282620 0.000041 0.001056 0.000029 0.049507 0.001041 1.467330 0.000131 41 of 41 716.5 0.282606 9.94 1.4 0.90 1.00 0.282325 0.282734 Hf Spot14 0.282607 0.000048 0.001369 0.000046 0.057239 0.002327 1.467355 0.000241 33 of 33 717.2 0.282588 9.33 1.7 0.92 1.04 0.282325 0.282734 Hf Spot15 0.282627 0.000043 0.001342 0.000108 0.051325 0.001604 1.467463 0.000139 37 of 37 728.7 0.282609 10.31 1.5 0.89 0.99 0.282318 0.282726
su average 0.282632 0.000041 0.001187 0.000058 0.049987 0.001804 1.467317 0.000130 715.7 0.282616 10.26 1.43 0.88 0.98 0.282326 0.282735
MudTank 159 0.282517 0.000023 0.000026 2.5E-07 0.001421 0.000036 1.467215 0.000145 109 of 110
MT. Std. 0.282507 0.000006
Plesovice 178 0.282474 0.000021 0.000110 0.000001 0.007097 0.000059 1.467273 0.000132 98 of 98 Plesovice 179 0.282472 0.000088 0.000088 0.000003 0.005667 0.000223 1.467241 0.000138 108 of 108 Ples. Std. 0.282482 0.000013
424 Table 3: Lu-Hf isotope data for zircons from the Jar-Salajah Complex (js) analysed by Multicollector-ICPMS. Raw values were processed using HfTrax software (Payne, 2010). Each spot represents a mean value created from the number of values analysed. Standard values for MudTank (Woodhead and Hergt, 2005) and Plesovice (Slama et al., 2008) were used to analyse the precision of the Multicollector. Raw 176Lu/177Hf values were used to calculate 176Hf/177Hf model values based on the 176Lu decay constant (1.87x10-11) after Scherer et al. (2001). The 176Lu decay constant and 206Pb/238U absolute age are used to calculate model ages TDM and TDMcrust with an average crustal composition of 0.015 (Griffin et al., 2002).
206Pb/238U 176Hf/177Hf TDM TDM 176Hf/177Hf 176Hf/177Hf Analysis No. 176Hf/177Hf 2σ 176Lu/177Hf 2σ 176Yb/177Hf 2σ 178Hf/177Hf 2σ No. Values ɛHf (T) 2σ (Ma) (T) (Ga) (Ga) of CHUR (T) of DM (T) Jar-Salajah Complex (js)-sample js202 Hf Spot1 0.282668 0.000040 0.001480 0.000039 0.062225 0.000771 1.467247 0.000099 98 of 98 679.1 0.282649 11.25 1.39 0.84 0.89 0.282349 0.282762 Hf Spot2 0.282623 0.000043 0.001417 0.000088 0.058841 0.001364 1.467318 0.000116 65 of 65 720.1 0.282604 9.94 1.51 0.90 1.01 0.282323 0.282732 Hf Spot3 0.282640 0.000054 0.001802 0.000115 0.083662 0.005890 1.467290 0.000169 31 of 31 697.1 0.282617 9.89 1.89 0.89 0.99 0.282338 0.282749 Hf Spot4 0.282651 0.000053 0.001542 0.000039 0.070031 0.001516 1.467358 0.000124 36 of 36 702.4 0.282631 10.51 1.86 0.86 0.96 0.282334 0.282745 Hf Spot5 0.282630 0.000051 0.001727 0.000025 0.075977 0.003309 1.467248 0.000180 33 of 33 719.6 0.282607 10.03 1.78 0.90 1.00 0.282323 0.282732 Hf Spot6 0.282620 0.000062 0.001541 0.000043 0.069825 0.002953 1.467219 0.000135 33 of 33 704.6 0.282600 9.45 2.17 0.91 1.03 0.282333 0.282743 Hf Spot7 0.282625 0.000048 0.001583 0.000111 0.071359 0.004317 1.467294 0.000153 33 of 33 690.3 0.282605 9.31 1.70 0.90 1.02 0.282342 0.282753 Hf Spot8 0.282649 0.000056 0.001462 0.000027 0.062685 0.001390 1.467268 0.000129 60 of 60 699 0.282629 10.38 1.94 0.87 0.96 0.282336 0.282747 Hf Spot9 0.282633 0.000040 0.001524 0.000026 0.064232 0.001143 1.467278 0.000070 109 of 109 707 0.282612 9.95 1.39 0.89 1.00 0.282331 0.282741 Hf Spot10 0.282646 0.000041 0.001392 0.000087 0.056511 0.004016 1.467232 0.000086 109 of 109 714.9 0.282627 10.64 1.45 0.87 0.96 0.282326 0.282736 Hf Spot11 0.282624 0.000052 0.001663 0.000134 0.065478 0.002280 1.467283 0.000103 72 of 73 711.5 0.282602 9.67 1.81 0.91 1.02 0.282329 0.282738 Hf Spot12 0.282638 0.000058 0.001870 0.000187 0.082875 0.005981 1.467280 0.000136 48 of 48 705 0.282613 9.92 2.05 0.89 1.00 0.282333 0.282743 Hf Spot13 0.282634 0.000067 0.002746 0.000337 0.135175 0.018288 1.467308 0.000113 61 of 61 677.1 0.282599 9.57 2.36 0.92 0.99 0.282350 0.282763 Hf Spot14 0.282608 0.000059 0.003203 0.000219 0.150777 0.010761 1.467299 0.000112 74 of 74 708.5 0.282566 8.34 2.08 0.97 1.10 0.282330 0.282740 Hf Spot15 0.282531 0.000160 0.005517 0.000759 0.269353 0.049638 1.467431 0.000206 34 of 34 684.7 0.282460 4.65 5.59 1.16 1.31 0.282345 0.282758 Hf Spot16 0.282714 0.000043 0.004119 0.000136 0.182013 0.004987 1.467240 0.000073 109 of 110 684.4 0.282661 11.79 1.51 0.83 0.86 0.282346 0.282758 Hf Spot17 0.282649 0.000045 0.001766 0.000122 0.080171 0.006383 1.467271 0.000086 89 of 89 681.4 0.282627 10.56 1.56 0.87 0.93 0.282347 0.282760 Hf Spot18 0.282604 0.000040 0.001205 0.000032 0.051454 0.001102 1.467266 0.000092 82 of 82 682.8 0.282588 9.19 1.40 0.92 1.02 0.282347 0.282759 Hf Spot19 0.282652 0.000144 0.017677 0.000735 0.885261 0.034391 1.467326 0.000099 60 of 61 670.4 0.282430 3.59 5.04 1.52 1.36 0.282354 0.282768
js average 0.282634 0.000061 0.002907 0.000172 0.135679 0.008446 1.467287 0.000120 696.8 0.282596 9.40 2.13 0.94 1.02 0.282338 0.282749
MudTank 173 0.282488 0.000021 0.000017 0.000000 0.000914 0.000021 1.467221 0.000073 93 of 93
MT. Std. 0.282507 0.000006
Plesovice 180 0.282479 0.000028 0.000080 0.000002 0.005332 0.000230 1.467287 0.000132 107 of 108 Plesovice 181 0.282472 0.000026 0.000088 0.000003 0.005667 0.000223 1.467241 0.000138 104 of 104 Ples. Std. 0.282482 0.000013
425 Table 4: Lu-Hf isotope data for zircons from the Subh Suite (sf) analysed by Multicollector-ICPMS. Raw values were processed using HfTrax software (Payne, 2010). Each spot represents a mean value created from the number of values analysed. Standard values for MudTank (Woodhead and Hergt, 2005) and Plesovice (Slama et al., 2008) were used to analyse the precision of the Multicollector. Raw 176Lu/177Hf values were used to calculate 176Hf/177Hf model values based on the 176Lu decay constant (1.87x10-11) after Scherer et al. (2001). The 176Lu decay constant and 206Pb/238U absolute age are used to calculate model ages TDM and TDMcrust with an average crustal composition of 0.015 (Griffin et al., 2002).
206Pb/238U 176Hf/177Hf TDM TDM 176Hf/177Hf 176Hf/177Hf Analysis No. 176Hf/177Hf 2σ 176Lu/177Hf 2σ 176Yb/177Hf 2σ 178Hf/177Hf 2σ No. Values ɛHf (T) 2σ (Ma) (T) (Ga) (Ga) of CHUR (T) of DM (T) Subh Suite (sf)-sample sf209 Hf Spot1 0.282631 0.000052 0.001627 0.000104 0.076333 0.004408 1.467242 0.000140 56 of 56 693.1 0.282610 9.55 1.8 0.90 1.01 0.282340 0.282751 Hf Spot2 0.282641 0.000079 0.003084 0.000444 0.109014 0.012674 1.467463 0.000151 49 of 50 702.7 0.282601 9.45 2.8 0.92 1.02 0.282334 0.282744 Hf Spot3 0.282659 0.000055 0.001893 0.000176 0.091209 0.007626 1.467156 0.000202 44 of 45 700.1 0.282634 10.56 1.9 0.86 0.95 0.282336 0.282746 Hf Spot4 0.282537 0.000129 0.002254 0.000174 0.119958 0.011462 1.467307 0.000289 10 of 10 698.9 0.282508 6.06 4.5 1.05 1.23 0.282336 0.282747 Hf Spot5 0.282626 0.000143 0.002777 0.000570 0.096187 0.014307 1.467454 0.000305 16 of 16 697.6 0.282589 8.93 5.0 0.93 1.05 0.282337 0.282748 Hf Spot6 0.282398 0.000261 0.008852 0.000737 0.308370 0.026804 1.467699 0.000203 25 of 25 693.9 0.282282 -2.03 9.1 1.52 1.73 0.282340 0.282751 Hf Spot7 0.282611 0.000054 0.001771 0.000047 0.082460 0.002976 1.467166 0.000122 59 of 59 705.4 0.282587 9.03 1.9 0.93 1.05 0.282332 0.282742 Hf Spot8 0.282628 0.000035 0.001318 0.000036 0.062709 0.002160 1.467297 0.000112 86 of 86 703.5 0.282611 9.82 1.2 0.89 1.00 0.282334 0.282744 Hf Spot9 0.282653 0.000064 0.003977 0.000300 0.128508 0.007666 1.467399 0.000149 53 of 53 699.2 0.282601 9.39 2.2 0.92 1.03 0.282336 0.282747
sf average 0.282598 0.000097 0.003061 0.000288 0.119417 0.010009 1.467353 0.000186 699.4 0.282558 7.86 3.38 0.99 1.12 0.282336 0.282747
MudTank 173 0.282488 0.000021 0.000017 0.000000 0.000914 0.000021 1.467221 0.000073 93 of 93
MT. Std. 0.282507 0.000006
Plesovice 183 0.282481 0.000024 0.000105 0.000001 0.006814 0.000099 1.467185 0.000118 104 of 104 Plesovice 184 0.282471 0.000024 0.000113 0.000000 0.007172 0.000031 1.467282 0.000105 92 of 92 Ples. Std. 0.282482 0.000013
426 Post-Orogenic Magmatism (~636-600 Ma) Post-Arabian Shield Terrane Accretion
427 Table 5: Lu-Hf isotope data for zircons from the Kawr Suite (kw) analysed by Multicollector-ICPMS. Raw values were processed using HfTrax software (Payne, 2010). Each spot represents a mean value created from the number of values analysed. Standard values for MudTank (Woodhead and Hergt, 2005) and Plesovice (Slama et al., 2008) were used to analyse the precision of the Multicollector. Raw 176Lu/177Hf values were used to calculate 176Hf/177Hf model values based on the 176Lu decay constant (1.87x10-11) after Scherer et al. (2001). The 176Lu decay constant and 206Pb/238U absolute age are used to calculate model ages TDM and TDMcrust with an average crustal composition of 0.015 (Griffin et al., 2002).
206Pb/238U 176Hf/177Hf TDM TDM 176Hf/177Hf 176Hf/177Hf Analysis No. 176Hf/177Hf 2σ 176Lu/177Hf 2σ 176Yb/177Hf 2σ 178Hf/177Hf 2σ No. Values ɛHf (T) 2σ (Ma) (T) (Ga) (Ga) of CHUR (T) of DM (T) Kawr Suite (kw)-sample kw42 Hf Spot1 0.282622 0.000034 0.001335 0.000039 0.062099 0.002493 1.467263 0.000095 96 of 96 621.2 0.282607 7.85 1.2 0.90 1.06 0.282385 0.282804 Hf Spot2 0.282598 0.000041 0.001463 0.000072 0.070633 0.002886 1.467359 0.000135 48 of 48 612.7 0.282581 6.76 1.4 0.94 1.12 0.282390 0.282810 Hf Spot3 0.282628 0.000047 0.001885 0.000255 0.074781 0.006775 1.467397 0.000188 59 of 59 613.3 0.282606 7.65 1.6 0.91 1.07 0.282390 0.282809 Hf Spot4 0.282567 0.000061 0.002299 0.000208 0.106636 0.005402 1.467309 0.000124 34 of 34 593.8 0.282541 4.92 2.1 1.01 1.23 0.282402 0.282823 Hf Spot5 0.282602 0.000089 0.002101 0.000282 0.112106 0.016134 1.467438 0.000268 21 of 21 618.2 0.282577 6.74 3.1 0.95 1.13 0.282387 0.282806 Hf Spot6 0.282651 0.000035 0.002151 0.000204 0.092330 0.005631 1.467210 0.000177 58 of 59 608.8 0.282626 8.26 1.2 0.88 1.03 0.282393 0.282813 Hf Spot7 0.282548 0.000102 0.003426 0.000137 0.116682 0.005141 1.467665 0.000212 51 of 51 612.5 0.282509 4.19 3.6 1.07 1.29 0.282391 0.282810 Hf Spot8 0.282552 0.000088 0.002095 0.000319 0.084592 0.007610 1.467079 0.000512 44 of 45 632.6 0.282527 5.29 3.1 1.02 1.23 0.282378 0.282795 Hf Spot9 0.282666 0.000044 0.001653 0.000102 0.086929 0.005693 1.467274 0.000122 39 of 39 600.1 0.282648 8.84 1.6 0.84 0.98 0.282398 0.282819 Hf Spot10 0.282618 0.000055 0.001942 0.000084 0.065143 0.002064 1.467347 0.000125 52 of 53 643.7 0.282595 7.92 1.9 0.92 1.07 0.282371 0.282787 Hf Spot11 0.282533 0.000088 0.002877 0.000172 0.117677 0.004492 1.467418 0.000229 35 of 35 630.7 0.282499 4.23 3.1 1.07 1.30 0.282379 0.282797
kw average 0.282599 0.000062 0.002112 0.000171 0.089964 0.005847 1.467342 0.000199 617.1 0.282574 6.60 2.18 0.95 1.14 0.282388 0.282807
MudTank 174 0.282502 0.000022 0.000017 0.000000 0.000884 0.000017 1.467254 0.000078 102 of 102
MT. Std. 0.282507 0.000006
Plesovice 205 0.282473 0.000017 0.000106 0.000001 0.006593 0.000046 1.467269 0.000149 96 of 96 Plesovice 206 0.282473 0.000017 0.000106 0.000001 0.006593 0.000046 1.467269 0.000149 100 of 100
428 Table 6: Lu-Hf isotope data for zircons from the Al Hafoor Suite (ao) analysed by Multicollector-ICPMS. Raw values were processed using HfTrax software (Payne, 2010). Each spot represents a mean value created from the number of values analysed. Standard values for MudTank (Woodhead and Hergt, 2005) and Plesovice (Slama et al., 2008) were used to analyse the precision of the Multicollector. Raw 176Lu/177Hf values were used to calculate 176Hf/177Hf model values based on the 176Lu decay constant (1.87x10-11) after Scherer et al. (2001). The 176Lu decay constant and 206Pb/238U absolute age are used to calculate model ages TDM and TDMcrust with an average crustal composition of 0.015 (Griffin et al., 2002).
206Pb/238U 176Hf/177Hf TDM TDM 176Hf/177Hf 176Hf/177Hf Analysis No. 176Hf/177Hf 2σ 176Lu/177Hf 2σ 176Yb/177Hf 2σ 178Hf/177Hf 2σ No. Values ɛHf (T) 2σ (Ma) (T) (Ga) (Ga) of CHUR (T) of DM (T) Al Hafoor Suite (ao)-sample ao85 Hf Spot1 0.282574 0.000041 0.001940 0.000053 0.089745 0.002865 1.467282 0.000096 102 of 102 628.9 0.282551 6.05 1.44 0.99 1.18 0.282380 0.282798 Hf Spot2 0.282618 0.000042 0.002096 0.000122 0.098566 0.005723 1.467268 0.000088 94 of 95 636.6 0.282593 7.69 1.47 0.93 1.08 0.282375 0.282792 Hf Spot3 0.282597 0.000055 0.002102 0.000104 0.103051 0.005296 1.467234 0.000108 64 of 64 633.1 0.282572 6.89 1.92 0.96 1.13 0.282378 0.282795 Hf Spot4 0.282633 0.000041 0.002081 0.000071 0.097203 0.003417 1.467245 0.000094 75 of 75 633.7 0.282608 8.18 1.44 0.90 1.05 0.282377 0.282794 Hf Spot5 0.282592 0.000038 0.001334 0.000100 0.057347 0.004341 1.467255 0.000123 60 of 60 632.2 0.282576 7.01 1.32 0.94 1.12 0.282378 0.282796 Hf Spot6 0.282611 0.000033 0.001509 0.000040 0.062084 0.001069 1.467250 0.000091 82 of 83 622.4 0.282593 7.40 1.17 0.92 1.09 0.282384 0.282803 Hf Spot7 0.282627 0.000040 0.003866 0.000073 0.170426 0.003265 1.467234 0.000078 81 of 81 634.5 0.282581 7.22 1.38 0.96 1.11 0.282377 0.282794 Hf Spot8 0.282610 0.000031 0.001245 0.000014 0.056407 0.001137 1.467224 0.000099 85 of 85 632.6 0.282595 7.69 1.10 0.92 1.08 0.282378 0.282795 Hf Spot9 0.282613 0.000039 0.002540 0.000133 0.113742 0.005880 1.467244 0.000087 107 of 108 641.8 0.282582 7.44 1.37 0.94 1.10 0.282372 0.282789 Hf Spot10 0.282602 0.000030 0.001073 0.000040 0.045548 0.001783 1.467296 0.000099 88 of 89 632.7 0.282589 7.47 1.04 0.92 1.09 0.282378 0.282795 Hf Spot11 0.282611 0.000034 0.001655 0.000061 0.068384 0.001584 1.467323 0.000125 68 of 69 641.7 0.282591 7.76 1.19 0.92 1.08 0.282372 0.282789 Hf Spot12 0.282633 0.000037 0.001490 0.000037 0.063790 0.001046 1.467222 0.000100 84 of 84 633.7 0.282615 8.42 1.30 0.89 1.04 0.282377 0.282794 Hf Spot13 0.282578 0.000033 0.001684 0.000046 0.073903 0.002025 1.467259 0.000080 102 of 103 647.2 0.282557 6.67 1.15 0.97 1.16 0.282369 0.282785
ao average 0.282608 0.000038 0.001893 0.000069 0.084630 0.003033 1.467257 0.000097 634.7 0.282585 7.38 1.33 0.94 1.10 0.282377 0.282794
MudTank 174 0.282502 0.000022 0.000017 0.000000 0.000884 0.000017 1.467254 0.000078 102 of 102
MT. Std. 0.282507 0.000006
Plesovice 207 0.282467 0.000018 0.000093 0.000003 0.005710 0.000219 1.467274 0.000147 105 of 105 Plesovice 208 0.282485 0.000020 0.000107 0.000001 0.006361 0.000046 1.467274 0.000136 99 of 99 Ples. Std. 0.282482 0.000013
429 Table 7: Lu-Hf isotope data for zircons from the Najirah Granite (nr) analysed by Multicollector-ICPMS. Raw values were processed using HfTrax software (Payne, 2010). Each spot represents a mean value created from the number of values analysed. Standard values for MudTank (Woodhead and Hergt, 2005) and Plesovice (Slama et al., 2008) were used to analyse the precision of the Multicollector. Raw 176Lu/177Hf values were used to calculate 176Hf/177Hf model values based on the 176Lu decay constant (1.87x10-11) after Scherer et al. (2001). The 176Lu decay constant and 206Pb/238U absolute age are used to calculate model ages TDM and TDMcrust with an average crustal composition of 0.015 (Griffin et al., 2002).
206Pb/238U 176Hf/177Hf TDM TDM 176Hf/177Hf 176Hf/177Hf Analysis No. 176Hf/177Hf 2σ 176Lu/177Hf 2σ 176Yb/177Hf 2σ 178Hf/177Hf 2σ No. Values ɛHf (T) 2σ (Ma) (T) (Ga) (Ga) of CHUR (T) of DM (T) Najirah Granite (nr)-sample nr120 Hf Spot1 0.282678 0.000033 0.001154 0.000068 0.058252 0.002846 1.467283 0.000128 44 of 44 603.3 0.282665 9.52 1.2 0.82 0.94 0.282396 0.282817 Hf Spot2 0.282630 0.000042 0.003145 0.000192 0.163352 0.010052 1.467244 0.000083 102 of 104 632 0.282593 7.61 1.5 0.93 1.09 0.282378 0.282796 Hf Spot3 0.282721 0.000066 0.003688 0.000461 0.193134 0.017825 1.467028 0.000146 35 of 36 601.6 0.282679 9.99 2.3 0.81 0.91 0.282397 0.282818 Hf Spot4 0.282625 0.000035 0.000875 0.000010 0.043257 0.000643 1.467319 0.000089 103 of 103 602.5 0.282615 7.74 1.2 0.89 1.05 0.282397 0.282817 Hf Spot5 0.282636 0.000034 0.002211 0.000057 0.114976 0.003224 1.467325 0.000082 98 of 98 605.1 0.282611 7.64 1.2 0.90 1.06 0.282395 0.282815 Hf Spot6 0.282613 0.000039 0.002633 0.000033 0.137266 0.003410 1.467282 0.000106 53 of 53 606.4 0.282583 6.68 1.4 0.95 1.12 0.282394 0.282814 Hf Spot7 0.282607 0.000034 0.000922 0.000024 0.045294 0.000943 1.467284 0.000112 66 of 67 584.8 0.282597 6.70 1.2 0.91 1.11 0.282408 0.282830 Hf Spot8 0.282635 0.000034 0.001485 0.000032 0.075722 0.001352 1.467238 0.000110 67 of 67 592 0.282618 7.61 1.2 0.89 1.05 0.282403 0.282825 Hf Spot9 0.282660 0.000061 0.002240 0.000105 0.117550 0.003950 1.467170 0.000120 72 of 72 586.7 0.282635 8.09 2.1 0.87 1.02 0.282407 0.282829 Hf Spot10 0.282640 0.000058 0.003592 0.000271 0.188111 0.010827 1.467184 0.000106 63 of 64 582.9 0.282601 6.79 2.0 0.93 1.10 0.282409 0.282831 Hf Spot11 0.282654 0.000063 0.001571 0.000054 0.085494 0.003312 1.467197 0.000118 41 of 41 634.7 0.282636 9.18 2.2 0.86 0.99 0.282377 0.282794 Hf Spot12 0.282600 0.000042 0.001545 0.000049 0.080426 0.003146 1.467224 0.000113 75 of 75 621.5 0.282582 6.98 1.5 0.94 1.12 0.282385 0.282803 Hf Spot13 0.282577 0.000058 0.003525 0.000352 0.193266 0.019822 1.467274 0.000098 56 of 56 580.4 0.282538 4.52 2.0 1.03 1.24 0.282411 0.282833 Hf Spot14 0.282586 0.000042 0.000897 0.000043 0.047407 0.003453 1.467271 0.000111 48 of 48 630.6 0.282575 6.95 1.5 0.94 1.13 0.282379 0.282797 Hf Spot15 0.282668 0.000063 0.001629 0.000066 0.085549 0.004745 1.467263 0.000124 38 of 38 583.6 0.282650 8.55 2.2 0.84 0.99 0.282409 0.282831 Hf Spot16 0.282629 0.000076 0.001997 0.000041 0.103951 0.002256 1.467323 0.000145 35 of 35 638 0.282605 8.16 2.7 0.91 1.06 0.282375 0.282791 Hf Spot17 0.282600 0.000058 0.001509 0.000140 0.087311 0.007958 1.467297 0.000126 48 of 48 613 0.282582 6.81 2.0 0.94 1.12 0.282390 0.282809
nr average 0.282633 0.000049 0.002036 0.000118 0.107078 0.005869 1.467247 0.000113 605.8 0.282610 7.62 1.73 0.90 1.06 0.282395 0.282815
MudTank 176 0.282509 0.000022 0.000015 0.000000 0.000814 0.000019 1.467332 0.000088 105 of 105
MT. Std. 0.282507 0.000006
Plesovice 209 0.282484 0.000020 0.000088 0.000002 0.005221 0.000159 1.467233 0.000147 105 of 105 Plesovice 211 0.282479 0.000021 0.000103 0.000002 0.006233 0.000101 1.467342 0.000175 87 of 87 Ples. Std. 0.282482 0.000013
430 Table 8: Lu-Hf isotope data for zircons from the Wadbah Suite (wb) analysed by Multicollector-ICPMS. Raw values were processed using HfTrax software (Payne, 2010). Each spot represents a mean value created from the number of values analysed. Standard values for MudTank (Woodhead and Hergt, 2005) and Plesovice (Slama et al., 2008) were used to analyse the precision of the Multicollector. Raw 176Lu/177Hf values were used to calculate 176Hf/177Hf model values based on the 176Lu decay constant (1.87x10-11) after Scherer et al. (2001). The 176Lu decay constant and 206Pb/238U absolute age are used to calculate model ages TDM and TDMcrust with an average crustal composition of 0.015 (Griffin et al., 2002).
206Pb/238U 176Hf/177Hf TDM TDM 176Hf/177Hf 176Hf/177Hf Analysis No. 176Hf/177Hf 2σ 176Lu/177Hf 2σ 176Yb/177Hf 2σ 178Hf/177Hf 2σ No. Values ɛHf (T) 2σ (Ma) (T) (Ga) (Ga) of CHUR (T) of DM (T) Wadbah Suite (wb)-sample wb65 Hf Spot1 0.282660 0.000039 0.000591 0.000010 0.026871 0.000472 1.467302 0.000102 55 of 55 626.5 0.282653 9.59 1.4 0.83 0.96 0.282382 0.282800 Hf Spot2 0.282626 0.000071 0.001148 0.000142 0.047301 0.002009 1.467417 0.000219 23 of 23 632.1 0.282613 8.30 2.5 0.89 1.04 0.282378 0.282796 Hf Spot3 0.282588 0.000038 0.001052 0.000040 0.045149 0.002441 1.467236 0.000102 62 of 63 619.4 0.282576 6.71 1.3 0.94 1.13 0.282386 0.282805 Hf Spot4 0.282675 0.000035 0.000777 0.000023 0.036557 0.001186 1.467271 0.000097 76 of 76 634.4 0.282665 10.22 1.2 0.81 0.92 0.282377 0.282794 Hf Spot5 0.282654 0.000049 0.001297 0.000161 0.048696 0.004095 1.467279 0.000112 39 of 39 636.9 0.282639 9.34 1.7 0.85 0.98 0.282375 0.282792 Hf Spot6 0.282643 0.000032 0.000611 0.000013 0.027717 0.000551 1.467260 0.000072 91 of 92 615.6 0.282636 8.75 1.1 0.85 1.00 0.282389 0.282808 Hf Spot7 0.282550 0.000075 0.000551 0.000022 0.025563 0.000874 1.467295 0.000172 19 of 19 609.5 0.282544 5.36 2.6 0.98 1.21 0.282392 0.282812 Hf Spot8 0.282629 0.000026 0.000896 0.000023 0.040138 0.000929 1.467233 0.000068 108 of 109 612.9 0.282619 8.10 0.9 0.88 1.04 0.282390 0.282810 Hf Spot9 0.282636 0.000052 0.001390 0.000120 0.049996 0.002495 1.467273 0.000098 80 of 81 606.8 0.282620 8.01 1.8 0.88 1.04 0.282394 0.282814 Hf Spot10 0.282675 0.000048 0.000947 0.000118 0.036320 0.002700 1.467316 0.000117 41 of 41 601.3 0.282664 9.43 1.7 0.82 0.95 0.282398 0.282818 Hf Spot11 0.282660 0.000027 0.000570 0.000038 0.027150 0.001529 1.467266 0.000137 40 of 41 611.8 0.282654 9.31 0.9 0.83 0.96 0.282391 0.282810 Hf Spot12 0.282656 0.000035 0.000916 0.000032 0.043935 0.001488 1.467269 0.000110 81 of 81 614.7 0.282646 9.08 1.2 0.84 0.98 0.282389 0.282808 Hf Spot13 0.282640 0.000050 0.001133 0.000037 0.054626 0.002323 1.467287 0.000163 30 of 30 608.2 0.282627 8.28 1.7 0.87 1.02 0.282393 0.282813 Hf Spot14 0.282639 0.000037 0.000848 0.000034 0.040895 0.002194 1.467271 0.000083 70 of 70 607.2 0.282629 8.33 1.3 0.87 1.02 0.282394 0.282814 Hf Spot15 0.282648 0.000034 0.000905 0.000064 0.036489 0.001399 1.467310 0.000085 88 of 90 619.9 0.282637 8.91 1.2 0.85 0.99 0.282386 0.282804 Hf Spot16 0.282641 0.000025 0.000536 0.000006 0.025644 0.000371 1.467215 0.000092 107 of 107 624.6 0.282635 8.93 0.9 0.85 1.00 0.282383 0.282801
wb average 0.282639 0.000042 0.000885 0.000055 0.038315 0.001691 1.467281 0.000114 617.6 0.282629 8.54 1.47 0.87 1.02 0.282387 0.282806
MudTank 176 0.282509 0.000022 0.000015 0.000000 0.000814 0.000019 1.467332 0.000088 105 of 105
MT. Std. 0.282507 0.000006
Plesovice 212 0.282479 0.000019 0.000103 0.000001 0.006300 0.000026 1.467214 0.000134 94 of 94 Plesovice 213 0.282483 0.000021 0.000116 0.000002 0.007279 0.000055 1.467277 0.000124 104 of 104 Ples. Std. 0.282482 0.000013
431 Table 9: Lu-Hf isotope data for zircons from the Ibn Hashbal Suite (ih) analysed by Multicollector-ICPMS. Raw values were processed using HfTrax software (Payne, 2010). Each spot represents a mean value created from the number of values analysed. Standard values for MudTank (Woodhead and Hergt, 2005) and Plesovice (Slama et al., 2008) were used to analyse the precision of the Multicollector. Raw 176Lu/177Hf values were used to calculate 176Hf/177Hf model values based on the 176Lu decay constant (1.87x10-11) after Scherer et al. (2001). The 176Lu decay constant and 206Pb/238U absolute age are used to calculate model ages TDM and TDMcrust with an average crustal composition of 0.015 (Griffin et al., 2002).
206Pb/238U 176Hf/177Hf TDM TDM 176Hf/177Hf 176Hf/177Hf Analysis No. 176Hf/177Hf 2σ 176Lu/177Hf 2σ 176Yb/177Hf 2σ 178Hf/177Hf 2σ No. Values ɛHf (T) 2σ (Ma) (T) (Ga) (Ga) of CHUR (T) of DM (T) Ibn Hashbal Suite (ih)-sample ih68 Hf Spot1 0.282671 0.000038 0.000857 0.000021 0.042349 0.000746 1.467236 0.000091 91 of 92 616.1 0.282662 9.68 1.3 0.82 0.94 0.282388 0.282807 Hf Spot2 0.282677 0.000085 0.003375 0.000414 0.182940 0.024798 1.467319 0.000166 61 of 61 633.1 0.282637 9.18 3.0 0.87 0.99 0.282378 0.282795 Hf Spot3 0.282746 0.000086 0.006060 0.000141 0.348235 0.011301 1.467285 0.000095 92 of 92 629.6 0.282674 10.41 3.0 0.83 0.91 0.282380 0.282797 Hf Spot4 0.282634 0.000031 0.000546 0.000010 0.026109 0.000348 1.467242 0.000084 105 of 106 604.7 0.282628 8.24 1.1 0.87 1.02 0.282395 0.282815 Hf Spot5 0.282670 0.000039 0.001231 0.000046 0.064107 0.003063 1.467272 0.000091 89 of 90 606.8 0.282656 9.29 1.4 0.83 0.96 0.282394 0.282814 Hf Spot6 0.282691 0.000037 0.001604 0.000104 0.082492 0.005250 1.467220 0.000082 102 of 102 615.1 0.282673 10.05 1.3 0.81 0.92 0.282389 0.282808 Hf Spot7 0.282613 0.000034 0.000555 0.000016 0.026034 0.000941 1.467274 0.000082 94 of 94 625.7 0.282607 7.95 1.2 0.89 1.06 0.282382 0.282800 Hf Spot8 0.282645 0.000030 0.000562 0.000005 0.026623 0.000424 1.467269 0.000097 104 of 104 632.4 0.282638 9.22 1.0 0.85 0.98 0.282378 0.282795 Hf Spot9 0.282687 0.000035 0.003471 0.000046 0.137085 0.003124 1.467334 0.000079 103 of 103 611.7 0.282647 9.06 1.2 0.86 0.98 0.282391 0.282810 Hf Spot10 0.282670 0.000040 0.001377 0.000032 0.068385 0.001230 1.467298 0.000091 94 of 94 601.7 0.282654 9.09 1.4 0.83 0.97 0.282397 0.282818 Hf Spot11 0.282617 0.000042 0.000648 0.000008 0.032121 0.000512 1.467232 0.000109 48 of 48 646.2 0.282609 8.50 1.5 0.89 1.04 0.282369 0.282785 Hf Spot12 0.282640 0.000036 0.000828 0.000030 0.040995 0.001258 1.467239 0.000082 79 of 79 626 0.282630 8.79 1.3 0.86 1.01 0.282382 0.282800 Hf Spot13 0.282631 0.000036 0.000476 0.000004 0.022177 0.000122 1.467294 0.000095 79 of 79 605.9 0.282625 8.16 1.2 0.87 1.03 0.282395 0.282815 Hf Spot14 0.282643 0.000036 0.000701 0.000032 0.032528 0.001427 1.467261 0.000090 112 of 112 609.2 0.282635 8.58 1.3 0.86 1.01 0.282393 0.282812 Hf Spot15 0.282697 0.000044 0.000662 0.000007 0.031540 0.000230 1.467284 0.000103 106 of 106 616.5 0.282690 10.68 1.5 0.78 0.88 0.282388 0.282807 Hf Spot16 0.282641 0.000033 0.000621 0.000003 0.030126 0.000521 1.467274 0.000123 114 of 115 615.8 0.282634 8.70 1.1 0.86 1.00 0.282389 0.282807
ih average 0.282661 0.000043 0.001473 0.000057 0.074615 0.003456 1.467271 0.000097 618.5 0.282644 9.10 1.49 0.85 0.98 0.282387 0.282805
MudTank 177 0.282489 0.000021 0.000022 0.000000 0.001211 0.000016 1.467284 0.000090 113 of 113
MT. Std. 0.282507 0.000006
Plesovice 214 0.282465 0.000018 0.000100 0.000002 0.006131 0.000083 1.467277 0.000131 103 of 103 Plesovice 215 0.282477 0.000019 0.000120 0.000003 0.007317 0.000144 1.467223 0.000110 104 of 105 Ples. Std. 0.282482 0.000013
432 Table 10: Lu-Hf isotope data for zircons from the Ar Ruwaydah Suite (ku) analysed by Multicollector-ICPMS. Raw values were processed using HfTrax software (Payne, 2010). Each spot represents a mean value created from the number of values analysed. Standard values for MudTank (Woodhead and Hergt, 2005) and Plesovice (Slama et al., 2008) were used to analyse the precision of the Multicollector. Raw 176Lu/177Hf values were used to calculate 176Hf/177Hf model values based on the 176Lu decay constant (1.87x10-11) after Scherer et al. (2001). The 176Lu decay constant and 206Pb/238U absolute age are used to calculate model ages TDM and TDMcrust with an average crustal composition of 0.015 (Griffin et al., 2002).
206Pb/238U 176Hf/177Hf TDM TDM 176Hf/177Hf 176Hf/177Hf Analysis No. 176Hf/177Hf 2σ 176Lu/177Hf 2σ 176Yb/177Hf 2σ 178Hf/177Hf 2σ No. Values ɛHf (T) 2σ (Ma) (T) (Ga) (Ga) of CHUR (T) of DM (T) Ar Ruwaydah Suite (ku)-sample ku139 Hf Spot1 0.282632 0.000020 0.001088 0.000025 0.048881 0.000884 1.467236 0.000080 106 of 106 625.2 0.282619 8.36 0.7 0.88 1.03 0.282383 0.282801 Hf Spot2 0.282619 0.000026 0.000924 0.000100 0.042244 0.004189 1.467013 0.000274 95 of 96 600.8 0.282609 7.46 0.9 0.90 1.07 0.282398 0.282818 Hf Spot3 0.282625 0.000025 0.001498 0.000026 0.069693 0.001132 1.467240 0.000066 85 of 85 604.3 0.282608 7.52 0.9 0.90 1.07 0.282396 0.282816 Hf Spot4 0.282669 0.000026 0.001120 0.000054 0.040796 0.000924 1.467346 0.000097 113 of 113 619.4 0.282656 9.56 0.9 0.83 0.95 0.282386 0.282805 Hf Spot5 0.282645 0.000027 0.001025 0.000054 0.045195 0.002713 1.467275 0.000072 103 of 103 614.7 0.282633 8.63 1.0 0.86 1.01 0.282389 0.282808 Hf Spot6 0.282617 0.000028 0.001306 0.000050 0.060546 0.002516 1.467338 0.000098 96 of 97 613.3 0.282602 7.51 1.0 0.91 1.08 0.282390 0.282809 Hf Spot7 0.282635 0.000022 0.001362 0.000028 0.062851 0.001668 1.467251 0.000077 93 of 95 629.4 0.282619 8.48 0.8 0.88 1.03 0.282380 0.282798 Hf Spot8 0.282639 0.000029 0.001197 0.000059 0.056169 0.002523 1.467298 0.000100 83 of 84 601.7 0.282625 8.07 1.0 0.87 1.03 0.282397 0.282818 Hf Spot9 0.282651 0.000031 0.001240 0.000074 0.057666 0.003390 1.467315 0.000092 93 of 93 604.8 0.282637 8.55 1.1 0.86 1.01 0.282395 0.282815 Hf Spot10 0.282624 0.000030 0.001360 0.000053 0.064937 0.002970 1.467261 0.000143 50 of 50 619.9 0.282609 7.88 1.1 0.90 1.06 0.282386 0.282804 Hf Spot11 0.282639 0.000025 0.001067 0.000051 0.051408 0.002368 1.467211 0.000084 88 of 88 625.8 0.282627 8.66 0.9 0.87 1.01 0.282382 0.282800 Hf Spot12 0.282693 0.000026 0.001032 0.000026 0.046944 0.001090 1.467236 0.000085 91 of 91 598.2 0.282681 9.98 0.9 0.79 0.91 0.282400 0.282820 Hf Spot13 0.282644 0.000020 0.000954 0.000022 0.043001 0.000704 1.467222 0.000080 110 of 112 619.4 0.282633 8.74 0.7 0.86 1.00 0.282386 0.282805
ku average 0.282641 0.000026 0.001167 0.000048 0.053102 0.002082 1.467249 0.000104 613.6 0.282628 8.41 0.91 0.87 1.02 0.282390 0.282809
MudTank 177 0.282489 0.000021 0.000022 0.000000 0.001211 0.000016 1.467284 0.000090 113 of 113
MT. Std. 0.282507 0.000006
Plesovice 216 0.282463 0.000019 0.000047 0.000001 0.002818 0.000029 1.467212 0.000139 103 of 103 Plesovice 217 0.282462 0.000021 0.000114 0.000002 0.006736 0.000081 1.467327 0.000152 101 of 101 Ples. Std. 0.282482 0.000013
433 Table 11: Lu-Hf isotope data for zircons from the Haml Suite (hla) analysed by Multicollector-ICPMS. Raw values were processed using HfTrax software (Payne, 2010). Each spot represents a mean value created from the number of values analysed. Standard values for MudTank (Woodhead and Hergt, 2005) and Plesovice (Slama et al., 2008) were used to analyse the precision of the Multicollector. Raw 176Lu/177Hf values were used to calculate 176Hf/177Hf model values based on the 176Lu decay constant (1.87x10-11) after Scherer et al. (2001). The 176Lu decay constant and 206Pb/238U absolute age are used to calculate model ages TDM and TDMcrust with an average crustal composition of 0.015 (Griffin et al., 2002).
206Pb/238U 176Hf/177Hf TDM TDM 176Hf/177Hf 176Hf/177Hf Analysis No. 176Hf/177Hf 2σ 176Lu/177Hf 2σ 176Yb/177Hf 2σ 178Hf/177Hf 2σ No. Values ɛHf (T) 2σ (Ma) (T) (Ga) (Ga) of CHUR (T) of DM (T) Haml Suite (hla)-sample hla110 Hf Spot1 0.282644 0.000027 0.000611 0.000037 0.026258 0.001408 1.467258 0.000071 91 of 91 627.2 0.282637 9.04 0.9 0.85 0.99 0.282381 0.282799 Hf Spot2 0.282655 0.000024 0.000563 0.000018 0.023770 0.000508 1.467220 0.000072 114 of 114 621.9 0.282648 9.34 0.8 0.84 0.97 0.282385 0.282803 Hf Spot3 0.282631 0.000035 0.001043 0.000033 0.045389 0.002510 1.467170 0.000099 32 of 33 613.1 0.282619 8.10 1.2 0.88 1.04 0.282390 0.282809 Hf Spot4 0.282655 0.000028 0.000853 0.000034 0.035560 0.001468 1.467289 0.000089 69 of 69 602.2 0.282646 8.81 1.0 0.84 0.99 0.282397 0.282817 Hf Spot5 0.282629 0.000031 0.000572 0.000033 0.025129 0.001548 1.467252 0.000142 30 of 30 603.3 0.282623 8.03 1.1 0.87 1.04 0.282396 0.282817 Hf Spot6 0.282674 0.000033 0.000992 0.000055 0.043214 0.002005 1.467259 0.000122 39 of 40 589.4 0.282663 9.13 1.2 0.82 0.96 0.282405 0.282827 Hf Spot7 0.282630 0.000023 0.000755 0.000007 0.030803 0.000494 1.467275 0.000077 103 of 103 604.6 0.282622 8.02 0.8 0.88 1.04 0.282396 0.282816 Hf Spot8 0.282651 0.000028 0.000793 0.000010 0.036311 0.000513 1.467297 0.000089 103 of 103 580.3 0.282642 8.19 1.0 0.85 1.01 0.282411 0.282833 Hf Spot9 0.282678 0.000035 0.000991 0.000032 0.042865 0.001937 1.467281 0.000097 69 of 69 627.7 0.282666 10.08 1.2 0.81 0.93 0.282381 0.282799 Hf Spot10 0.282669 0.000028 0.000687 0.000046 0.030941 0.001648 1.467249 0.000099 65 of 65 601.1 0.282661 9.32 1.0 0.82 0.95 0.282398 0.282818 Hf Spot11 0.282653 0.000037 0.001448 0.000085 0.057735 0.003698 1.467238 0.000131 53 of 53 613.1 0.282636 8.70 1.3 0.86 1.00 0.282390 0.282809 Hf Spot12 0.282671 0.000052 0.001555 0.000070 0.068332 0.004398 1.467284 0.000132 44 of 44 625.3 0.282653 9.58 1.8 0.84 0.96 0.282383 0.282801 Hf Spot13 0.282638 0.000034 0.001145 0.000070 0.049267 0.003306 1.467267 0.000102 58 of 58 612.7 0.282624 8.28 1.2 0.87 1.03 0.282390 0.282810 Hf Spot14 0.282639 0.000038 0.001000 0.000060 0.041500 0.002235 1.467359 0.000109 50 of 50 597.1 0.282628 8.07 1.3 0.87 1.03 0.282400 0.282821 Hf Spot15 0.282709 0.000071 0.002385 0.000172 0.108407 0.010107 1.467293 0.000124 30 of 30 600.7 0.282682 10.06 2.5 0.80 0.91 0.282398 0.282818
hla average 0.282655 0.000035 0.001026 0.000051 0.044365 0.002519 1.467266 0.000104 608.0 0.282643 8.9 1.2 0.8 1.0 0.282393 0.282813
MudTank 178 0.282484 0.000019 0.000018 0.000000 0.000967 0.000018 1.467279 0.000088 111 of 111
MT. Std. 0.282507 0.000006
Plesovice 218 0.282471 0.000021 0.000109 0.000002 0.006572 0.000139 1.467217 0.000126 96 of 96 Plesovice 219 0.282452 0.000019 0.000102 0.000002 0.006206 0.000095 1.467234 0.000137 103 of 103 Ples. Std. 0.282482 0.000013
434 Table 12: Lu-Hf isotope data for zircons from the Kawr Suite (kw) analysed by Multicollector-ICPMS. Raw values were processed using HfTrax software (Payne, 2010). Each spot represents a mean value created from the number of values analysed. Standard values for MudTank (Woodhead and Hergt, 2005) and Plesovice (Slama et al., 2008) were used to analyse the precision of the Multicollector. Raw 176Lu/177Hf values were used to calculate 176Hf/177Hf model values based on the 176Lu decay constant (1.87x10-11) after Scherer et al. (2001). The 176Lu decay constant and 206Pb/238U absolute age are used to calculate model ages TDM and TDMcrust with an average crustal composition of 0.015 (Griffin et al., 2002).
206Pb/238U 176Hf/177Hf TDM TDM 176Hf/177Hf 176Hf/177Hf Analysis No. 176Hf/177Hf 2σ 176Lu/177Hf 2σ 176Yb/177Hf 2σ 178Hf/177Hf 2σ No. Values ɛHf (T) 2σ (Ma) (T) (Ga) (Ga) of CHUR (T) of DM (T) Kawr Suite (kw)-sample kw51p Hf Spot1 0.282690 0.000030 0.001118 0.000036 0.057492 0.002084 1.467292 0.000157 96 of 97 612.5 0.282677 10.14 1.1 0.80 0.91 0.282391 0.282810 Hf Spot2 0.282647 0.000018 0.000611 0.000024 0.029404 0.001170 1.467228 0.000126 95 of 95 588.8 0.282640 8.31 0.6 0.85 1.01 0.282405 0.282827 Hf Spot3 0.282860 0.000052 0.006187 0.000067 0.290886 0.002265 1.467205 0.000099 100 of 101 613.9 0.282789 14.14 1.8 0.64 0.66 0.282390 0.282809 Hf Spot4 0.282770 0.000034 0.003591 0.000069 0.161094 0.002581 1.467238 0.000105 104 of 105 605.5 0.282729 11.84 1.2 0.73 0.80 0.282395 0.282815 Hf Spot5 0.282689 0.000042 0.001543 0.000032 0.073938 0.002100 1.467211 0.000155 69 of 69 607.3 0.282671 9.83 1.5 0.81 0.93 0.282394 0.282814 Hf Spot6 0.282686 0.000038 0.001099 0.000036 0.054119 0.001386 1.467214 0.000189 30 of 30 632.6 0.282673 10.44 1.3 0.80 0.91 0.282378 0.282795 Hf Spot7 0.282615 0.000018 0.000325 0.000035 0.012352 0.000839 1.467344 0.000182 67 of 67 604.1 0.282611 7.63 0.6 0.89 1.06 0.282396 0.282816 Hf Spot8 0.282623 0.000038 0.000915 0.000076 0.041408 0.004216 1.467250 0.000140 39 of 39 643.7 0.282612 8.53 1.3 0.89 1.04 0.282371 0.282787 Hf Spot9 0.282753 0.000036 0.002734 0.000126 0.118645 0.004093 1.467208 0.000144 69 of 69 576.9 0.282724 11.01 1.3 0.74 0.83 0.282413 0.282836 Hf Spot10 0.282671 0.000049 0.001243 0.000086 0.060594 0.003332 1.467278 0.000320 33 of 33 600.1 0.282657 9.15 1.7 0.83 0.96 0.282398 0.282819 Hf Spot11 0.282644 0.000018 0.000460 0.000027 0.019753 0.000861 1.467250 0.000127 86 of 87 622.1 0.282639 9.00 0.6 0.85 0.99 0.282385 0.282803
kw average 0.282695 0.000034 0.001802 0.000056 0.083608 0.002266 1.467247 0.000159 609.8 0.282675 10.00 1.19 0.80 0.92 0.282392 0.282812
MudTank 178 0.282484 0.000019 0.000018 0.000000 0.000967 0.000018 1.467279 0.000088 111 of 111
MT. Std. 0.282507 0.000006
Plesovice 220 0.282464 0.000023 0.000089 0.000003 0.005446 0.000212 1.467356 0.000121 100 of 101 Plesovice 221 0.282497 0.000019 0.000100 0.000002 0.006168 0.000083 1.467301 0.000151 86 of 87 Ples. Std. 0.282482 0.000013
435 Table 13: Lu-Hf isotope data for zircons from the Idah Suite (id) analysed by Multicollector-ICPMS. Raw values were processed using HfTrax software (Payne, 2010). Each spot represents a mean value created from the number of values analysed. Standard values for MudTank (Woodhead and Hergt, 2005) and Plesovice (Slama et al., 2008) were used to analyse the precision of the Multicollector. Raw 176Lu/177Hf values were used to calculate 176Hf/177Hf model values based on the 176Lu decay constant (1.87x10-11) after Scherer et al. (2001). The 176Lu decay constant and 206Pb/238U absolute age are used to calculate model ages TDM and TDMcrust with an average crustal composition of 0.015 (Griffin et al., 2002).
206Pb/238U 176Hf/177Hf TDM TDM 176Hf/177Hf 176Hf/177Hf Analysis No. 176Hf/177Hf 2σ 176Lu/177Hf 2σ 176Yb/177Hf 2σ 178Hf/177Hf 2σ No. Values ɛHf (T) 2σ (Ma) (T) (Ga) (Ga) of CHUR (T) of DM (T) Idah Suite (id)-sample id159 Hf Spot1 0.282627 0.000073 0.002392 0.000063 0.119872 0.002059 1.467295 0.000223 24 of 24 605.4 0.282599 7.24 2.6 0.92 1.09 0.282395 0.282815 Hf Spot2 0.282662 0.000047 0.001616 0.000099 0.070291 0.002930 1.467069 0.000109 45 of 45 598.8 0.282644 8.66 1.6 0.85 0.99 0.282399 0.282820 Hf Spot3 0.282677 0.000034 0.001314 0.000081 0.060943 0.002876 1.467229 0.000091 83 of 83 636.8 0.282661 10.13 1.2 0.82 0.93 0.282375 0.282792 Hf Spot4 0.282648 0.000039 0.001880 0.000125 0.097738 0.008136 1.467206 0.000089 87 of 87 612.2 0.282626 8.34 1.3 0.88 1.02 0.282391 0.282810 Hf Spot5 0.282665 0.000032 0.000869 0.000080 0.039207 0.004083 1.467212 0.000124 60 of 60 614.8 0.282655 9.41 1.1 0.83 0.96 0.282389 0.282808 Hf Spot6 0.282623 0.000043 0.001698 0.000088 0.085019 0.005483 1.467212 0.000118 82 of 82 603.6 0.282604 7.34 1.5 0.91 1.08 0.282396 0.282816 Hf Spot7 0.282648 0.000041 0.001809 0.000060 0.089589 0.002878 1.467245 0.000089 73 of 74 621.7 0.282627 8.57 1.4 0.87 1.02 0.282385 0.282803 Hf Spot8 0.282608 0.000042 0.001779 0.000053 0.098734 0.003860 1.467288 0.000109 69 of 69 614.5 0.282587 7.01 1.5 0.93 1.11 0.282389 0.282808 Hf Spot9 0.282657 0.000044 0.000943 0.000048 0.044766 0.001526 1.467236 0.000167 43 of 43 600.5 0.282646 8.79 1.5 0.84 0.99 0.282398 0.282819 Hf Spot10 0.282718 0.000035 0.001638 0.000061 0.083347 0.003172 1.467232 0.000090 92 of 93 621.7 0.282699 11.11 1.2 0.77 0.86 0.282385 0.282803 Hf Spot11 0.282713 0.000052 0.003218 0.000216 0.156974 0.006562 1.467364 0.000094 71 of 72 612.8 0.282676 10.12 1.8 0.81 0.91 0.282390 0.282810 Hf Spot12 0.282612 0.000055 0.002406 0.000161 0.136240 0.008899 1.467216 0.000107 54 of 55 605.4 0.282584 6.70 1.9 0.94 1.12 0.282395 0.282815 Hf Spot13 0.282665 0.000053 0.002758 0.000066 0.150731 0.004824 1.467206 0.000120 32 of 32 636.8 0.282632 9.08 1.8 0.87 1.00 0.282375 0.282792 Hf Spot14 0.282637 0.000050 0.001665 0.000116 0.076312 0.002793 1.467351 0.000147 43 of 43 597.6 0.282618 7.74 1.7 0.89 1.05 0.282400 0.282821
id average 0.282654 0.000046 0.001856 0.000094 0.093554 0.004292 1.467240 0.000120 613.0 0.282633 8.59 1.60 0.87 1.01 0.282390 0.282809
MudTank 179 0.282508 0.000024 0.000014 0.000000 0.000641 0.000014 1.467291 0.000086 110 of 111
MT. Std. 0.282507 0.000006
Plesovice 222 0.282495 0.000020 0.000101 0.000001 0.006088 0.000069 1.467256 0.000128 96 of 96 Plesovice 223 0.282477 0.000021 0.000089 0.000002 0.005560 0.000091 1.467287 0.000133 107 of 107 Ples. Std. 0.282482 0.000013
436 Table 14: Lu-Hf isotope data for zircons from the Al Khushaymiyah Suite (ky) analysed by Multicollector-ICPMS. Raw values were processed using HfTrax software (Payne, 2010). Each spot represents a mean value created from the number of values analysed. Standard values for MudTank (Woodhead and Hergt, 2005) and Plesovice (Slama et al., 2008) were used to analyse the precision of the Multicollector. Raw 176Lu/177Hf values were used to calculate 176Hf/177Hf model values based on the 176Lu decay constant (1.87x10-11) after Scherer et al. (2001). The 176Lu decay constant and 206Pb/238U absolute age are used to calculate model ages TDM and TDMcrust with an average crustal composition of 0.015 (Griffin et al., 2002).
206Pb/238U 176Hf/177Hf TDM TDM 176Hf/177Hf 176Hf/177Hf Analysis No. 176Hf/177Hf 2σ 176Lu/177Hf 2σ 176Yb/177Hf 2σ 178Hf/177Hf 2σ No. Values ɛHf (T) 2σ (Ma) (T) (Ga) (Ga) of CHUR (T) of DM (T) Al Khushaymiyah Suite (ky)-sample ky129 Hf Spot1 0.282614 0.000030 0.002033 0.000043 0.086738 0.001892 1.467275 0.000088 103 of 103 590.4 0.282592 6.63 1.0 0.93 1.11 0.282404 0.282826 Hf Spot2 0.282580 0.000029 0.001280 0.000020 0.054466 0.001133 1.467294 0.000073 85 of 86 623.5 0.282565 6.41 1.0 0.96 1.15 0.282384 0.282802 Hf Spot3 0.282527 0.000038 0.001463 0.000016 0.064812 0.000973 1.467334 0.000089 63 of 63 603 0.282510 4.02 1.3 1.04 1.29 0.282397 0.282817 Hf Spot4 0.282586 0.000027 0.001477 0.000053 0.066830 0.001787 1.467257 0.000087 91 of 92 597.9 0.282569 6.00 1.0 0.96 1.16 0.282400 0.282820 Hf Spot5 0.282563 0.000032 0.001198 0.000032 0.054438 0.001755 1.467216 0.000100 88 of 88 607.6 0.282549 5.50 1.1 0.98 1.20 0.282394 0.282813 Hf Spot6 0.282514 0.000042 0.002210 0.000084 0.097144 0.004343 1.467264 0.000083 90 of 90 612 0.282488 3.46 1.5 1.08 1.33 0.282391 0.282810 Hf Spot7 0.282575 0.000034 0.001208 0.000035 0.051086 0.001410 1.467261 0.000075 99 of 99 607 0.282561 5.93 1.2 0.96 1.17 0.282394 0.282814 Hf Spot8 0.282577 0.000039 0.001443 0.000066 0.063526 0.002179 1.467290 0.000112 60 of 60 603.3 0.282561 5.83 1.4 0.97 1.18 0.282396 0.282817 Hf Spot9 0.282520 0.000032 0.001338 0.000049 0.061610 0.001980 1.467310 0.000094 74 of 74 601.6 0.282505 3.82 1.1 1.05 1.30 0.282397 0.282818 Hf Spot10 0.282580 0.000031 0.001601 0.000048 0.068469 0.001728 1.467236 0.000090 104 of 104 597.8 0.282562 5.76 1.1 0.97 1.18 0.282400 0.282820 Hf Spot11 0.282570 0.000031 0.001564 0.000091 0.066297 0.003580 1.467277 0.000086 97 of 97 591.2 0.282553 5.28 1.1 0.98 1.20 0.282404 0.282825 Hf Spot12 0.282564 0.000034 0.000958 0.000061 0.040589 0.002837 1.467214 0.000102 75 of 75 590 0.282553 5.26 1.2 0.97 1.20 0.282405 0.282826 Hf Spot13 0.282529 0.000028 0.000346 0.000006 0.014750 0.000144 1.467244 0.000091 105 of 106 618.7 0.282525 4.89 1.0 1.01 1.25 0.282387 0.282805 Hf Spot14 0.282558 0.000025 0.000517 0.000013 0.022423 0.000714 1.467285 0.000071 103 of 103 587.9 0.282553 5.20 0.9 0.97 1.20 0.282406 0.282828 Hf Spot15 0.282571 0.000029 0.001535 0.000034 0.066988 0.002228 1.467305 0.000086 101 of 102 608 0.282553 5.65 1.0 0.98 1.19 0.282393 0.282813 Hf Spot16 0.282562 0.000028 0.001399 0.000077 0.062590 0.003169 1.467292 0.000080 91 of 91 618.1 0.282546 5.63 1.0 0.99 1.20 0.282387 0.282806 Hf Spot17 0.282563 0.000031 0.001103 0.000033 0.046779 0.001702 1.467256 0.000094 82 of 82 586.3 0.282551 5.09 1.1 0.98 1.21 0.282407 0.282829
ky average 0.282562 0.000032 0.001334 0.000045 0.058208 0.001974 1.467271 0.000088 602.6 0.282547 5.31 1.11 0.99 1.21 0.282397 0.282817
MudTank 179 0.282508 0.000024 0.000014 0.000000 0.000641 0.000014 1.467291 0.000086 110 of 111
MT. Std. 0.282507 0.000006
Plesovice 224 0.282459 0.000021 0.000120 0.000003 0.007411 0.000137 1.467266 0.000107 106 of 106 Plesovice 225 0.282464 0.000020 0.000122 0.000002 0.007322 0.000067 1.467317 0.000141 96 of 96 Ples. Std. 0.282482 0.000013
437 Anorogenic Magmatism (<600 Ma) Post-Arabian Shield Terrane Accretion
438 Table 15: Lu-Hf isotope data for zircons from the Malik Granite (kg) analysed by Multicollector-ICPMS. Raw values were processed using HfTrax software (Payne, 2010). Each spot represents a mean value created from the number of values analysed. Standard values for MudTank (Woodhead and Hergt, 2005) and Plesovice (Slama et al., 2008) were used to analyse the precision of the Multicollector. Raw 176Lu/177Hf values were used to calculate 176Hf/177Hf model values based on the 176Lu decay constant (1.87x10-11) after Scherer et al. (2001). The 176Lu decay constant and 206Pb/238U absolute age are used to calculate model ages TDM and TDMcrust with an average crustal composition of 0.015 (Griffin et al., 2002).
206Pb/238U 176Hf/177Hf TDM TDM 176Hf/177Hf 176Hf/177Hf Analysis No. 176Hf/177Hf 2σ 176Lu/177Hf 2σ 176Yb/177Hf 2σ 178Hf/177Hf 2σ No. Values ɛHf (T) 2σ (Ma) (T) (Ga) (Ga) of CHUR (T) of DM (T) Malik Granite (kg)-sample kg150 Hf Spot1 0.282645 0.000033 0.001591 0.000070 0.080602 0.003523 1.467220 0.000099 69 of 69 597.6 0.282627 8.04 1.2 0.87 1.03 0.282400 0.282821 Hf Spot2 0.282669 0.000074 0.005486 0.000448 0.253938 0.023955 1.467312 0.000110 48 of 48 603.2 0.282607 7.44 2.6 0.94 1.07 0.282396 0.282817 Hf Spot3 0.282696 0.000059 0.004803 0.000377 0.224356 0.009215 1.467276 0.000075 85 of 85 599.9 0.282642 8.63 2.1 0.88 1.00 0.282398 0.282819 Hf Spot4 0.282640 0.000054 0.001855 0.000265 0.088293 0.011675 1.467089 0.000115 66 of 67 599.6 0.282619 7.81 1.9 0.89 1.05 0.282399 0.282819 Hf Spot5 0.282687 0.000036 0.001177 0.000029 0.063057 0.002136 1.467199 0.000083 105 of 107 602.9 0.282673 9.80 1.3 0.81 0.92 0.282397 0.282817 Hf Spot6 0.282706 0.000057 0.004454 0.000095 0.246606 0.004338 1.467271 0.000082 106 of 106 609.1 0.282655 9.30 2.0 0.85 0.96 0.282393 0.282812
kg average 0.282674 0.000052 0.003228 0.000214 0.159475 0.009140 1.467228 0.000094 602.1 0.282637 8.50 1.83 0.87 1.01 0.282397 0.282817
MudTank 180 0.282516 0.000023 0.000019 0.000000 0.001460 0.000023 1.467328 0.000097 104 of 104
MT. Std. 0.282507 0.000006
Plesovice 226 0.282470 0.000018 0.000112 0.000002 0.006800 0.000076 1.467309 0.000135 106 of 107 Plesovice 228 0.282471 0.000021 0.000098 0.000002 0.006065 0.000096 1.467258 0.000150 107 of 107 Ples. Std. 0.282482 0.000013
439 Table 16: Lu-Hf isotope data for zircons from the Admar Suite (ad) analysed by Multicollector-ICPMS. Raw values were processed using HfTrax software (Payne, 2010). Each spot represents a mean value created from the number of values analysed. Standard values for MudTank (Woodhead and Hergt, 2005) and Plesovice (Slama et al., 2008) were used to analyse the precision of the Multicollector. Raw 176Lu/177Hf values were used to calculate 176Hf/177Hf model values based on the 176Lu decay constant (1.87x10-11) after Scherer et al. (2001). The 176Lu decay constant and 206Pb/238U absolute age are used to calculate model ages TDM and TDMcrust with an average crustal composition of 0.015 (Griffin et al., 2002).
206Pb/238U 176Hf/177Hf TDM TDM 176Hf/177Hf 176Hf/177Hf Analysis No. 176Hf/177Hf 2σ 176Lu/177Hf 2σ 176Yb/177Hf 2σ 178Hf/177Hf 2σ No. Values ɛHf (T) 2σ (Ma) (T) (Ga) (Ga) of CHUR (T) of DM (T) Admar Suite (ad)-sample ad194 Hf Spot1 0.282649 0.000041 0.000477 0.000005 0.020687 0.000156 1.467247 0.000088 116 of 116 600.7 0.282644 8.70 1.43 0.84 0.99 0.282398 0.282818 Hf Spot2 0.282663 0.000040 0.000709 0.000022 0.031328 0.001368 1.467316 0.000071 109 of 109 593 0.282655 8.93 1.39 0.83 0.97 0.282403 0.282824 Hf Spot3 0.282620 0.000041 0.000496 0.000019 0.021649 0.000497 1.467284 0.000101 92 of 92 596.3 0.282614 7.55 1.45 0.88 1.06 0.282401 0.282822 Hf Spot4 0.282596 0.000038 0.000570 0.000010 0.025173 0.000421 1.467262 0.000083 111 of 112 604 0.282589 6.84 1.33 0.92 1.11 0.282396 0.282816 Hf Spot5 0.282634 0.000035 0.000383 0.000003 0.017073 0.000280 1.467252 0.000116 111 of 113 600.7 0.282630 8.20 1.22 0.86 1.02 0.282398 0.282818 Hf Spot6 0.282605 0.000038 0.000386 0.000002 0.017468 0.000270 1.467320 0.000098 91 of 91 605.6 0.282601 7.29 1.33 0.90 1.09 0.282395 0.282815 Hf Spot7 0.282627 0.000040 0.000955 0.000029 0.044606 0.001414 1.467220 0.000108 95 of 95 600.4 0.282616 7.71 1.41 0.89 1.05 0.282398 0.282819 Hf Spot8 0.282608 0.000041 0.000594 0.000016 0.026690 0.000974 1.467236 0.000085 114 of 114 599 0.282601 7.17 1.43 0.90 1.09 0.282399 0.282820 Hf Spot9 0.282574 0.000045 0.000370 0.000006 0.016289 0.000428 1.467312 0.000078 89 of 90 592.3 0.282570 5.91 1.59 0.94 1.16 0.282403 0.282824 Hf Spot10 0.282663 0.000039 0.000339 0.000004 0.015195 0.000143 1.467306 0.000096 89 of 90 589 0.282659 8.98 1.35 0.82 0.97 0.282405 0.282827 Hf Spot11 0.282668 0.000035 0.000690 0.000011 0.031716 0.000365 1.467331 0.000081 108 of 109 593.3 0.282661 9.14 1.24 0.82 0.96 0.282403 0.282824 Hf Spot12 0.282660 0.000042 0.000366 0.000006 0.016252 0.000386 1.467249 0.000110 74 of 74 599.7 0.282656 9.13 1.48 0.82 0.96 0.282399 0.282819 Hf Spot13 0.282584 0.000036 0.000441 0.000005 0.019505 0.000135 1.467217 0.000095 105 of 105 596.3 0.282579 6.32 1.25 0.93 1.14 0.282401 0.282822 Hf Spot14 0.282689 0.000041 0.000995 0.000050 0.045532 0.002183 1.467255 0.000089 98 of 99 602.9 0.282678 9.95 1.42 0.80 0.92 0.282397 0.282817 Hf Spot15 0.282673 0.000050 0.000910 0.000088 0.041994 0.004037 1.467278 0.000086 100 of 100 601.6 0.282663 9.39 1.74 0.82 0.95 0.282397 0.282818
ad average 0.282634 0.000040 0.000579 0.000018 0.026077 0.000871 1.467272 0.000092 598.3 0.282628 8.08 1.40 0.87 1.03 0.282399 0.282820
MudTank 180 0.282516 0.000023 0.000019 0.000000 0.001460 0.000023 1.467328 0.000097 104 of 104
MT. Std. 0.282507 0.000006
Plesovice 229 0.282472 0.000024 0.000081 0.000001 0.004993 0.000056 1.405068 0.000202 99 of 100 Plesovice 230 0.282463 0.000019 0.000081 0.000001 0.004418 0.000040 1.467285 0.000176 107 of 107 Ples. Std. 0.282482 0.000013
440 Table 17: Lu-Hf isotope data for zircons from the Al Bad Granite Suite (abg) analysed by Multicollector-ICPMS. Raw values were processed using HfTrax software (Payne, 2010). Each spot represents a mean value created from the number of values analysed. Standard values for MudTank (Woodhead and Hergt, 2005) and Plesovice (Slama et al., 2008) were used to analyse the precision of the Multicollector. Raw 176Lu/177Hf values were used to calculate 176Hf/177Hf model values based on the 176Lu decay constant (1.87x10-11) after Scherer et al. (2001). The 176Lu decay constant and 206Pb/238U absolute age are used to calculate model ages TDM and TDMcrust with an average crustal composition of 0.015 (Griffin et al., 2002).
206Pb/238U 176Hf/177Hf TDM TDM 176Hf/177Hf 176Hf/177Hf Analysis No. 176Hf/177Hf 2σ 176Lu/177Hf 2σ 176Yb/177Hf 2σ 178Hf/177Hf 2σ No. Values ɛHf (T) 2σ (Ma) (T) (Ga) (Ga) of CHUR (T) of DM (T) Al Bad Granite Super Suite (abg)-sample abg179 Hf Spot1 0.282648 0.000036 0.001427 0.000035 0.061275 0.001414 1.467258 0.000082 116 of 116 611.9 0.282632 8.52 1.27 0.87 1.01 0.282391 0.282810 Hf Spot2 0.282673 0.000038 0.001996 0.000021 0.096566 0.001699 1.467288 0.000097 85 of 85 599.3 0.282651 8.92 1.31 0.84 0.98 0.282399 0.282819 Hf Spot3 0.282603 0.000034 0.000806 0.000016 0.035113 0.000811 1.467212 0.000081 72 of 72 604.1 0.282594 7.02 1.20 0.91 1.10 0.282396 0.282816 Hf Spot4 0.282675 0.000048 0.002108 0.000105 0.094144 0.005636 1.467292 0.000090 65 of 65 606.7 0.282651 9.11 1.66 0.84 0.97 0.282394 0.282814 Hf Spot5 0.282640 0.000031 0.001224 0.000058 0.051298 0.001701 1.467280 0.000108 98 of 98 600.1 0.282626 8.06 1.08 0.87 1.03 0.282398 0.282819 Hf Spot6 0.282644 0.000034 0.001221 0.000039 0.051487 0.001887 1.467232 0.000085 115 of 115 596.1 0.282630 8.12 1.19 0.87 1.03 0.282401 0.282822 Hf Spot7 0.282655 0.000031 0.001408 0.000045 0.059057 0.001644 1.467226 0.000084 114 of 114 587.2 0.282639 8.24 1.08 0.86 1.01 0.282406 0.282828 Hf Spot8 0.282633 0.000037 0.002590 0.000081 0.130946 0.004718 1.467289 0.000086 96 of 96 593.7 0.282604 7.13 1.31 0.92 1.09 0.282402 0.282823 Hf Spot9 0.282653 0.000045 0.002559 0.000082 0.128143 0.002635 1.467263 0.000114 83 of 83 601.4 0.282624 8.02 1.56 0.89 1.04 0.282398 0.282818 Hf Spot10 0.282621 0.000061 0.002979 0.000121 0.155211 0.008174 1.467341 0.000126 58 of 58 588.5 0.282588 6.45 2.14 0.94 1.12 0.282406 0.282827 Hf Spot11 0.282703 0.000043 0.003211 0.000109 0.165141 0.005700 1.467249 0.000087 89 of 90 608.3 0.282667 9.69 1.51 0.83 0.94 0.282393 0.282813 Hf Spot12 0.282685 0.000040 0.002144 0.000075 0.110493 0.005364 1.467235 0.000109 78 of 78 600 0.282660 9.28 1.39 0.83 0.96 0.282398 0.282819 Hf Spot13 0.282719 0.000045 0.002695 0.000221 0.109859 0.005136 1.467337 0.000149 73 of 74 607.7 0.282688 10.43 1.58 0.79 0.89 0.282394 0.282813 Hf Spot14 0.282640 0.000039 0.002255 0.000112 0.101171 0.003430 1.467237 0.000115 60 of 60 584.7 0.282616 7.35 1.37 0.90 1.07 0.282408 0.282830 Hf Spot15 0.282650 0.000036 0.002347 0.000051 0.112864 0.001018 1.467230 0.000101 100 of 100 607 0.282623 8.11 1.24 0.89 1.03 0.282394 0.282814
abg average 0.282656 0.000040 0.002065 0.000078 0.097518 0.003398 1.467265 0.000101 599.8 0.282633 8.30 1.39 0.87 1.02 0.282399 0.282819
MudTank 181 0.282502 0.000022 0.000017 0.000000 0.000884 0.000017 1.467254 0.000078 102 of 102
MT. Std. 0.282507 0.000006
Plesovice 231 0.282483 0.000021 0.000116 0.000002 0.007279 0.000055 1.467277 0.000124 111 of 111 Plesovice 232 0.282465 0.000018 0.000100 0.000002 0.006131 0.000083 1.467277 0.000131 98 of 98 Ples. Std. 0.282482 0.000013
441 Table 18: Lu-Hf isotope data for zircons from the Al Hawiyah Suite (hwg) analysed by Multicollector-ICPMS. Raw values were processed using HfTrax software (Payne, 2010). Each spot represents a mean value created from the number of values analysed. Standard values for (Woodhead and Hergt, 2005) and Plesovice (Slama et al., 2008) were used to analyse the precision of the Multicollector. Raw 176Lu/177Hf values were used to calculate 176Hf/177Hf model values based on the 176Lu decay constant (1.87x10-11) after Scherer et al. (2001). The 176Lu decay constant and 206Pb/238U absolute age are used to calculate model ages TDM and TDMcrust with an average crustal composition of 0.015 (Griffin et al., 2002).
206Pb/238U 176Hf/177Hf TDM TDM 176Hf/177Hf 176Hf/177Hf Analysis No. 176Hf/177Hf 2σ 176Lu/177Hf 2σ 176Yb/177Hf 2σ 178Hf/177Hf 2σ No. Values ɛHf (T) 2σ (Ma) (T) (Ga) (Ga) of CHUR (T) of DM (T) Al Hawiyah Suite (hwg)-sample hwg07 Hf Spot1 0.282662 0.000035 0.001680 0.000050 0.083865 0.002729 1.467079 0.000094 41 of 41 613.6 0.282643 8.95 1.24 0.85 0.99 0.282390 0.282809 Hf Spot2 0.282623 0.000034 0.001789 0.000118 0.081658 0.003909 1.467265 0.000097 76 of 76 622.0 0.282603 7.72 1.17 0.91 1.07 0.282385 0.282803 Hf Spot3 0.282636 0.000031 0.001390 0.000048 0.064869 0.002745 1.467343 0.000097 77 of 77 603.4 0.282621 7.94 1.09 0.88 1.04 0.282396 0.282816 Hf Spot4 0.282621 0.000031 0.001168 0.000062 0.053655 0.002251 1.467254 0.000101 68 of 69 601.1 0.282607 7.43 1.08 0.90 1.07 0.282398 0.282818 Hf Spot5 0.282676 0.000029 0.001551 0.000097 0.072057 0.003942 1.467205 0.000078 81 of 81 597.1 0.282658 9.14 1.01 0.83 0.96 0.282400 0.282821 Hf Spot6 0.282670 0.000047 0.003395 0.000161 0.173802 0.007272 1.467175 0.000103 76 of 76 594.4 0.282632 8.16 1.64 0.88 1.02 0.282402 0.282823 Hf Spot7 0.282614 0.000043 0.002586 0.000138 0.119149 0.006572 1.467201 0.000121 73 of 73 588.8 0.282585 6.37 1.52 0.94 1.13 0.282405 0.282827 Hf Spot8 0.282640 0.000031 0.000810 0.000050 0.036156 0.001854 1.467232 0.000095 83 of 83 591.9 0.282631 8.07 1.09 0.86 1.03 0.282403 0.282825 Hf Spot9 0.282606 0.000036 0.001698 0.000198 0.065879 0.004921 1.467236 0.000165 74 of 75 587.8 0.282588 6.43 1.27 0.93 1.13 0.282406 0.282828 Hf Spot10 0.282618 0.000032 0.001660 0.000101 0.079645 0.003809 1.467281 0.000138 58 of 59 585.3 0.282600 6.80 1.14 0.91 1.10 0.282408 0.282830 Hf Spot11 0.282623 0.000026 0.001597 0.000107 0.067626 0.003273 1.467252 0.000101 82 of 82 592.6 0.282605 7.15 0.92 0.91 1.08 0.282403 0.282824 Hf Spot12 0.282623 0.000023 0.000638 0.000017 0.028219 0.000453 1.467282 0.000069 103 of 103 598.5 0.282616 7.66 0.81 0.88 1.06 0.282399 0.282820 Hf Spot13 0.282627 0.000027 0.001217 0.000075 0.050712 0.002353 1.467168 0.000097 68 of 69 566.0 0.282614 6.87 0.94 0.89 1.08 0.282420 0.282844 Hf Spot14 0.282665 0.000038 0.002337 0.000067 0.105739 0.001579 1.467273 0.000090 79 of 79 575.5 0.282640 8.01 1.33 0.86 1.02 0.282414 0.282837
hwg average 0.282636 0.000033 0.001680 0.000092 0.077359 0.003404 1.467232 0.000103 594.1 0.282617 7.62 1.16 0.89 1.06 0.282402 0.282823
MudTank 181 0.282502 0.000022 0.000017 0.000000 0.000884 0.000017 1.467254 0.000078 102 of 102
MT. Std. 0.282507 0.000006
Plesovice 233 0.282485 0.000020 0.000107 0.000001 0.006361 0.000046 1.467274 0.000136 100 of 100 Plesovice 234 0.282484 0.000020 0.000088 0.000002 0.005221 0.000159 1.467233 0.000147 99 of 99 Ples. Std. 0.282482 0.000013
442 Table 19: Lu-Hf isotope data for zircons from the Mardabah Complex (mr) analysed by Multicollector-ICPMS. Raw values were processed using HfTrax software (Payne, 2010). Each spot represents a mean value created from the number of values analysed. Standard values for (Woodhead and Hergt, 2005) and Plesovice (Slama et al., 2008) were used to analyse the precision of the Multicollector. Raw 176Lu/177Hf values were used to calculate 176Hf/177Hf model values based on the 176Lu decay constant (1.87x10-11) after Scherer et al. (2001). The 176Lu decay constant and 206Pb/238U absolute age are used to calculate model ages TDM and TDMcrust with an average crustal composition of 0.015 (Griffin et al., 2002).
206Pb/238U 176Hf/177Hf TDM TDM 176Hf/177Hf 176Hf/177Hf Analysis No. 176Hf/177Hf 2σ 176Lu/177Hf 2σ 176Yb/177Hf 2σ 178Hf/177Hf 2σ No. Values ɛHf (T) 2σ (Ma) (T) (Ga) (Ga) of CHUR (T) of DM (T) Mardabah Complex (mr)-sample mr191 Hf Spot1 0.282733 0.000050 0.001427 0.000029 0.077979 0.000812 1.467268 0.000089 112 of 112 526.7 0.282719 9.73 1.7 0.74 0.87 0.282444 0.282872 Hf Spot2 0.282665 0.000041 0.000522 0.000004 0.026965 0.000442 1.467281 0.000093 106 of 106 534.8 0.282660 7.80 1.4 0.82 1.00 0.282439 0.282866 Hf Spot3 0.282650 0.000045 0.000633 0.000012 0.031523 0.000382 1.467296 0.000080 102 of 103 542 0.282644 7.40 1.6 0.84 1.03 0.282435 0.282861 Hf Spot4 0.282659 0.000050 0.001387 0.000016 0.069242 0.001078 1.467254 0.000095 102 of 102 532.1 0.282645 7.23 1.7 0.85 1.03 0.282441 0.282868 Hf Spot5 0.282709 0.000035 0.000506 0.000010 0.025548 0.000677 1.467288 0.000091 101 of 102 531 0.282704 9.31 1.2 0.76 0.90 0.282442 0.282869 Hf Spot6 0.282653 0.000041 0.000477 0.000001 0.024314 0.000170 1.467301 0.000109 98 of 98 514.9 0.282648 6.97 1.4 0.84 1.04 0.282452 0.282880 Hf Spot7 0.282705 0.000043 0.000595 0.000037 0.031593 0.002407 1.467255 0.000080 107 of 108 520.9 0.282699 8.90 1.5 0.77 0.92 0.282448 0.282876 Hf Spot8 0.282669 0.000044 0.001024 0.000103 0.058227 0.006578 1.467273 0.000097 83 of 83 522.9 0.282659 7.51 1.5 0.83 1.01 0.282447 0.282875 Hf Spot9 0.282691 0.000044 0.001596 0.000137 0.091872 0.008827 1.467239 0.000089 108 of 108 524.4 0.282675 8.11 1.6 0.81 0.97 0.282446 0.282874 Hf Spot10 0.282632 0.000050 0.001206 0.000004 0.064219 0.000536 1.467259 0.000083 112 of 112 529.1 0.282620 6.27 1.8 0.88 1.09 0.282443 0.282870 Hf Spot11 0.282586 0.000040 0.000513 0.000009 0.026744 0.000346 1.467250 0.000092 112 of 112 521.5 0.282581 4.74 1.4 0.93 1.18 0.282448 0.282876 Hf Spot12 0.282658 0.000048 0.001124 0.000023 0.057758 0.001757 1.467238 0.000083 106 of 107 509.9 0.282648 6.83 1.7 0.84 1.04 0.282455 0.282884 Hf Spot13 0.282655 0.000044 0.000540 0.000001 0.027714 0.000341 1.467301 0.000098 97 of 98 518.9 0.282650 7.12 1.6 0.84 1.03 0.282449 0.282878 Hf Spot14 0.282672 0.000050 0.001632 0.000040 0.085527 0.001565 1.467294 0.000103 101 of 102 522.9 0.282656 7.41 1.8 0.84 1.01 0.282447 0.282875 Hf Spot15 0.282663 0.000043 0.001447 0.000030 0.076075 0.001144 1.467240 0.000098 109 of 109 523.7 0.282649 7.18 1.5 0.84 1.03 0.282446 0.282874
mr average 0.282667 0.000045 0.000975 0.000030 0.051687 0.001804 1.467269 0.000092 525.0 0.282657 7.50 1.56 0.83 1.01 0.282445 0.282873
MudTank 181 0.282502 0.000022 0.000017 0.000000 0.000884 0.000017 1.467254 0.000078 102 of 102
MT. Std. 0.282507 0.000006
Plesovice 236 0.282472 0.000026 0.000088 0.000003 0.005667 0.000223 1.467241 0.000138 102 of 102 Plesovice 234 0.282467 0.000027 0.000108 0.000002 0.006821 0.000078 1.467265 0.000104 106 of 106 Ples. Std. 0.282482 0.000013
443 Appendix 5: Whole Rock Major and Trace Element Data; Ferrous Iron Determination
444 Table 1: Arabian Shield samples analysed for major elements by X-Ray Fluorescence (XRF). These analyses were preformed on a Philips PW 1480 X-ray Fluorescence Spectrometer using an analysis program calibrated against several international (BHVO-1and BCR-1) and local (TASBAS) standard reference materials. The analysis method is described in Appendix a3. A complementary sample catalogue is displayed in Appendix 1.
Sample Map unit SiO2 % Al2O3 % Fe2O3T % MnO % MgO % CaO % Na2O % K2O % TiO2 % P2O5 % SO3 % LOI % Total %
aa 166 74.38 10.76 4.19 0.04 0.10 0.29 3.80 4.91 0.42 0.01 0.01 0.48 99.39 aa 167 Abanat Suite 75.12 10.64 3.65 0.03 0.10 0.27 3.67 4.86 0.34 0.01 0.01 0.50 99.20 aa 168 75.61 10.10 4.05 0.05 0.10 0.29 3.68 4.66 0.32 0.01 0.01 0.41 99.28 abg 171 76.52 12.88 0.61 0.09 0.12 0.38 4.38 4.30 0.06 0.00 0.01 0.41 99.74 abg 172 76.02 12.85 0.67 0.06 0.09 0.36 4.43 4.29 0.05 0.01 0.01 0.43 99.26 abg 173 Al Bad Granite 75.99 12.76 0.70 0.07 0.11 0.33 4.52 4.33 0.05 0.00 0.01 0.39 99.28 abg 178 Super Suite 78.14 11.42 0.93 0.02 0.13 0.08 3.84 4.07 0.09 0.01 0.01 0.40 99.15 abg 179 76.23 12.49 0.98 0.03 0.15 0.28 4.18 4.59 0.12 0.01 0.01 0.40 99.47 abg 180 76.21 12.56 0.85 0.06 0.15 0.25 4.23 4.55 0.12 0.01 0.01 0.41 99.39 ad 194 60.82 18.37 3.24 0.07 0.93 2.27 5.08 5.99 0.89 0.24 0.02 0.31 98.21 ad 195 61.18 18.49 3.14 0.06 0.87 2.18 5.06 6.12 0.85 0.22 0.01 0.31 98.50 Admar Suite ad 196 60.68 18.45 3.54 0.07 1.01 2.27 5.10 5.91 0.93 0.24 0.02 0.31 98.52 ad 197 61.04 18.56 3.31 0.06 0.94 2.17 5.10 6.04 0.84 0.20 0.02 0.32 98.58 ao 83 76.08 12.29 1.13 0.04 0.20 0.66 3.42 4.85 0.09 0.02 0.01 0.58 99.35 ao 85 76.00 12.36 1.15 0.04 0.19 0.68 3.45 4.89 0.09 0.02 0.01 0.62 99.50 ao 87 50.67 16.67 9.27 0.16 8.10 10.09 2.01 0.61 0.51 0.13 0.02 1.96 100.19 Al Hafoor Suite ao 88 50.23 17.09 9.10 0.15 7.78 9.92 2.05 0.65 0.47 0.14 0.02 2.24 99.83 ao 98 68.70 15.58 1.71 0.03 1.26 2.98 4.62 2.98 0.22 0.08 0.01 1.12 99.29 ao 101 68.80 15.67 1.67 0.03 1.21 2.77 4.71 2.96 0.22 0.08 0.01 0.92 99.04 ay 186 62.23 16.35 5.75 0.08 4.15 2.39 5.69 0.80 0.64 0.16 0.01 1.45 99.68 ay 187 Al Ays Group 62.81 15.59 5.39 0.10 3.93 3.72 5.45 0.58 0.69 0.16 0.01 1.04 99.49 ay 206 49.63 16.04 11.13 0.17 6.85 10.25 2.99 0.36 1.34 0.27 0.01 0.77 99.80 CV 192 Mardabah 59.76 16.83 7.51 0.24 1.03 3.20 6.55 2.87 0.88 0.24 0.01 0.25 99.37 CV 193 Complex 59.55 16.76 7.51 0.24 1.00 3.24 6.42 2.85 0.87 0.23 0.01 0.24 98.92 dm 01a 54.13 15.47 9.46 0.16 4.89 7.26 3.35 1.69 1.32 0.45 0.02 1.48 99.67 dm 01b Makkah Suite 51.81 15.97 10.82 0.17 6.25 8.51 3.01 1.03 1.21 0.26 0.04 0.96 100.03 dm 01c 64.34 15.74 5.59 0.08 1.36 3.82 4.41 2.18 0.73 0.25 0.01 0.63 99.15 hla 109 67.89 16.05 2.45 0.06 0.73 1.99 4.66 4.62 0.33 0.09 0.01 0.38 99.27 hla 110 68.04 15.96 2.43 0.06 0.71 2.00 4.58 4.75 0.33 0.10 0.01 0.41 99.38 Haml Suite hla 111 71.24 14.39 2.13 0.05 0.61 1.52 3.98 4.69 0.29 0.08 0.01 0.30 99.27 hla 112 70.39 14.72 2.21 0.06 0.67 1.77 4.11 4.70 0.29 0.08 0.01 0.38 99.39
445 Table 1 (continued): Arabian Shield samples analysed for major elements by X-Ray Fluorescence (XRF). These analyses were preformed on a Philips PW 1480 X-ray Fluorescence Spectrometer using an analysis program calibrated against several international (BHVO-1and BCR-1) and local (TASBAS) standard reference materials. The analysis method is described in Appendix a3. A complementary sample catalogue is displayed in Appendix 1.
Sample Map Unit SiO2 % Al2O3 % Fe2O3T % MnO % MgO % CaO % Na2O % K2O % TiO2 % P2O5 % SO3 % LOI % Total %
hn 160 68.78 14.89 3.61 0.07 0.55 2.11 5.00 3.15 0.65 0.16 0.01 0.60 99.56 Hadn Formation hn 162 75.20 10.35 4.19 0.07 0.06 0.36 4.20 4.63 0.27 0.01 0.01 0.25 99.59 hwg 03 76.51 12.62 0.76 0.01 0.10 0.73 3.31 5.24 0.04 0.01 0.01 0.33 99.66 hwg 04 65.51 15.03 5.00 0.10 1.21 2.86 3.76 3.82 0.98 0.44 0.02 0.62 99.35 hwg 07 Al Hawiyah Suite 71.43 14.00 2.31 0.05 0.43 1.19 3.15 5.92 0.25 0.10 0.02 0.61 99.43 hwg 08 72.45 14.00 1.82 0.04 0.26 1.09 3.50 5.63 0.16 0.05 0.01 0.44 99.44 hwg 09 72.94 14.08 1.82 0.04 0.26 1.05 3.67 5.27 0.17 0.04 0.01 0.39 99.74 id 155 74.92 13.50 1.02 0.05 0.12 0.56 4.18 5.00 0.08 0.02 0.01 0.34 99.79 id 156 75.27 13.34 1.03 0.05 0.12 0.57 4.14 4.79 0.09 0.02 0.01 0.35 99.77 id 159 Idah Suite 75.43 12.95 1.24 0.06 0.14 0.58 4.15 4.48 0.10 0.02 0.01 0.36 99.52 id 163 76.28 12.87 0.86 0.03 0.08 0.40 4.20 4.54 0.05 0.01 0.01 0.33 99.65 id 164 76.24 12.91 0.96 0.03 0.07 0.43 4.25 4.47 0.05 0.01 0.01 0.33 99.74 ih 66 74.48 12.40 2.19 0.04 0.35 0.80 2.78 5.92 0.38 0.06 0.01 0.43 99.83 ih 68 74.71 12.39 1.90 0.04 0.23 0.63 2.82 6.24 0.31 0.04 0.01 0.28 99.61 ih 73 71.92 14.67 1.45 0.03 0.44 1.58 3.74 4.75 0.25 0.08 0.01 0.49 99.40 Ibn Hashbal Suite ih 74 71.86 14.66 1.52 0.03 0.46 1.58 3.77 4.73 0.26 0.07 0.01 0.49 99.43 ih 76 71.62 14.82 1.54 0.03 0.48 1.58 3.85 4.67 0.27 0.07 0.01 0.45 99.39 ih 79 71.99 14.63 1.43 0.03 0.44 1.41 3.71 4.83 0.25 0.07 0.01 0.56 99.35 kg 142 74.34 14.12 0.88 0.25 0.15 1.31 3.34 4.90 0.01 0.02 0.01 0.19 99.51 kg 145 74.00 14.45 0.27 0.07 0.10 1.07 3.13 6.14 0.01 0.03 0.01 0.24 99.51 kg 146 Malik Granite 74.99 13.96 0.22 0.06 0.09 1.23 3.31 5.20 0.01 0.03 0.01 0.21 99.32 kg 148 74.56 14.06 0.71 0.02 0.18 0.82 3.43 5.45 0.07 0.04 0.01 0.42 99.77 kg 150 74.01 13.92 1.07 0.03 0.24 0.97 3.40 5.12 0.11 0.04 0.01 0.56 99.49 ku 121 75.29 13.12 1.05 0.02 0.09 0.70 3.75 4.98 0.06 0.01 0.01 0.53 99.60 ku 122 75.82 12.86 1.01 0.02 0.09 0.71 3.65 4.87 0.06 0.01 0.02 0.53 99.63 Ar Ruwaydah Suite ku 123 75.18 12.99 1.20 0.02 0.09 0.59 3.74 4.89 0.07 0.01 0.01 0.50 99.27 ku 139 74.27 13.93 0.78 0.01 0.17 1.07 3.15 5.93 0.06 0.03 0.01 0.29 99.68 kw 10 60.78 15.52 5.70 0.10 4.59 8.26 2.47 0.23 0.44 0.08 0.01 1.72 99.89 kw 11 56.98 16.16 6.75 0.12 5.54 9.03 2.30 0.27 0.53 0.09 0.02 2.35 100.12 kw 13 Kawr Suite 75.53 11.16 3.12 0.07 0.06 0.42 3.92 4.83 0.27 0.01 0.01 0.14 99.55 kw 14 44.90 22.42 4.84 0.07 11.05 10.70 2.04 0.10 0.08 0.06 0.04 3.99 100.29 kw 15 45.97 25.04 3.39 0.05 8.00 11.62 2.51 0.16 0.08 0.06 0.03 3.69 100.60
446 Table 1 (continued): Arabian Shield samples analysed for major elements by X-Ray Fluorescence (XRF). These analyses were preformed on a Philips PW 1480 X-ray Fluorescence Spectrometer using an analysis program calibrated against several international (BHVO-1and BCR-1) and local (TASBAS) standard reference materials. The analysis method is described in Appendix a3. A complementary sample catalogue is displayed in Appendix 1.
Sample Map Unit SiO2 % Al2O3 % Fe2O3T % MnO % MgO % CaO % Na2O % K2O % TiO2 % P2O5 % SO3 % LOI % Total %
kw 16 46.06 25.31 3.52 0.05 7.48 12.06 2.32 0.27 0.08 0.06 0.06 3.30 100.54 kw 18 43.94 21.19 5.14 0.07 13.35 9.98 1.85 0.12 0.06 0.05 0.03 4.24 100.02 kw 19 45.52 22.30 4.70 0.07 11.40 11.09 2.08 0.04 0.10 0.06 0.04 2.82 100.21 kw 21 74.46 11.44 3.34 0.07 0.07 0.44 4.01 5.00 0.30 0.02 0.01 0.15 99.30 kw 22 74.86 11.14 3.50 0.07 0.07 0.44 3.93 4.92 0.31 0.01 0.01 0.15 99.41 kw 23 75.14 11.07 3.40 0.07 0.07 0.42 3.93 4.83 0.30 0.01 0.01 0.10 99.33 kw 24 76.02 10.77 3.23 0.06 0.06 0.34 3.85 4.58 0.30 0.01 0.01 0.13 99.36 kw 29 74.87 12.47 1.84 0.01 0.21 0.52 3.31 5.41 0.22 0.02 0.01 0.56 99.45 kw 30b 60.35 13.93 7.74 0.13 3.41 4.73 3.59 2.84 1.55 0.32 0.02 1.23 99.84 kw 30p 74.72 12.37 1.69 0.01 0.48 0.85 3.06 5.24 0.25 0.03 0.01 0.60 99.31 kw 31 75.35 12.32 1.68 0.01 0.19 0.48 3.29 5.36 0.18 0.02 0.01 0.49 99.39 kw 32 57.43 14.19 8.85 0.15 3.98 5.48 3.66 2.41 1.80 0.38 0.02 1.27 99.60 kw 33 59.85 13.88 7.92 0.13 3.56 4.98 3.47 2.79 1.56 0.31 0.01 1.21 99.65 kw 35 69.45 13.22 3.85 0.05 1.26 1.91 3.71 4.22 0.67 0.11 0.01 0.60 99.06 kw 36 Kawr Suite 73.62 12.97 2.04 0.02 0.33 0.75 3.35 5.49 0.27 0.03 0.01 0.34 99.20 kw 38 74.65 12.18 2.33 0.04 0.21 0.52 3.84 5.07 0.24 0.02 0.01 0.23 99.34 kw 40 76.15 12.74 0.89 0.03 0.13 0.59 3.86 4.57 0.09 0.02 0.01 0.12 99.20 kw 41 74.74 13.44 1.10 0.03 0.30 1.06 3.96 4.12 0.16 0.03 0.01 0.36 99.32 kw 42 67.05 14.03 5.56 0.10 1.47 2.47 5.04 2.26 0.76 0.27 0.02 0.36 99.38 kw 43 54.77 15.60 8.22 0.28 4.28 16.40 0.55 0.04 0.81 0.28 0.01 0.00 101.12 kw 44 72.21 14.65 1.40 0.05 0.39 1.38 4.34 4.24 0.19 0.05 0.01 0.58 99.47 kw 45 71.92 14.66 1.46 0.04 0.41 1.46 4.33 4.07 0.20 0.06 0.01 0.58 99.20 kw 46 74.93 12.72 1.71 0.02 0.25 0.54 3.38 5.51 0.22 0.02 0.01 0.28 99.59 kw 50 71.34 14.75 1.57 0.04 0.47 1.53 4.37 4.02 0.23 0.07 0.01 0.62 99.02 kw 51b 71.83 14.77 1.59 0.03 0.46 1.44 4.36 3.94 0.22 0.05 0.01 0.53 99.23 kw 51p 75.60 12.93 0.87 0.02 0.13 0.61 3.74 5.00 0.13 0.01 0.01 0.26 99.30 kw 52b 71.90 14.73 1.52 0.03 0.45 1.44 4.35 3.93 0.21 0.05 0.01 0.52 99.13 kw 52p 75.36 12.98 0.96 0.02 0.15 0.61 3.68 5.19 0.14 0.02 0.01 0.26 99.37 kw 55 57.16 15.85 8.22 0.18 4.33 12.38 0.84 0.13 0.89 0.27 0.02 0.14 100.39 ky 124 70.93 15.47 0.76 0.01 0.28 1.63 5.32 3.53 0.10 0.03 0.01 1.17 99.25 Al Khushaymiyah Suite ky 125 71.33 15.09 0.74 0.01 0.27 1.72 5.22 3.36 0.10 0.03 0.01 1.26 99.14
447 Table 1 (continued): Arabian Shield samples analysed for major elements by X-Ray Fluorescence (XRF). These analyses were preformed on a Philips PW 1480 X-ray Fluorescence Spectrometer using an analysis program calibrated against several international (BHVO-1and BCR-1) and local (TASBAS) standard reference materials. The analysis method is described in Appendix a3. A complementary sample catalogue is displayed in Appendix 1.
Sample Map Unit SiO2 % Al2O3 % Fe2O3T % MnO % MgO % CaO % Na2O % K2O % TiO2 % P2O5 % SO3 % LOI % Total %
ky 126 Al Khushaymiyah 71.63 15.18 0.78 0.01 0.28 1.64 5.24 3.31 0.10 0.03 0.01 1.19 99.41 ky 129 64.18 17.72 2.73 0.04 0.96 2.56 4.96 4.71 0.45 0.20 0.01 0.39 98.91 ky 130 Suite 63.57 17.91 2.84 0.04 1.02 2.72 4.96 4.56 0.47 0.23 0.01 0.43 98.74 MCR 104 47.21 15.63 10.53 0.21 9.14 9.01 2.14 2.12 1.21 0.23 0.01 2.51 99.95 Bani Ghayy Group MCR 105 49.77 16.13 9.39 0.17 6.43 9.31 3.88 1.08 1.05 0.22 0.01 2.10 99.54 MD 93 69.43 16.03 1.60 0.03 0.83 2.51 5.02 2.73 0.27 0.10 0.02 0.63 99.19 Al Hafoor Suite MD 95 69.69 16.09 1.59 0.03 0.85 2.56 5.12 2.75 0.27 0.10 0.02 0.68 99.74 mr 188 60.08 18.49 4.40 0.14 0.91 2.96 6.66 3.13 0.76 0.19 0.01 1.02 98.76 mr 189 59.80 18.53 4.24 0.14 0.89 3.16 6.76 3.01 0.77 0.20 0.02 1.18 98.69 Mardabah Complex mr 190 60.01 18.26 4.48 0.16 0.77 3.09 6.75 3.10 0.79 0.20 0.02 0.98 98.59 mr 191 60.35 18.06 4.53 0.16 0.78 3.01 6.65 3.14 0.72 0.18 0.02 1.12 98.70 mu 131 52.80 16.48 8.49 0.10 4.44 6.20 4.00 2.28 1.48 0.45 0.14 2.55 99.41 mu 132 53.36 16.61 8.07 0.10 4.12 5.77 4.32 2.31 1.33 0.44 0.04 2.79 99.26 Murdama Group mv 134 68.62 14.51 3.31 0.04 0.93 1.82 3.72 3.91 0.38 0.13 0.03 2.05 99.44 mv 135 70.41 14.89 3.06 0.03 0.91 2.23 3.77 3.47 0.37 0.12 0.02 0.13 99.42 nr 117 73.93 13.35 1.56 0.03 0.28 0.97 3.27 5.33 0.15 0.08 0.01 0.36 99.32 nr 119 74.33 13.18 1.46 0.03 0.27 0.98 3.17 5.30 0.15 0.08 0.01 0.44 99.39 Najirah Granite nr 120 74.44 13.25 1.48 0.03 0.27 0.98 3.21 5.38 0.15 0.07 0.01 0.39 99.65 nr 136 75.12 12.16 2.15 0.02 0.11 0.39 2.29 6.80 0.14 0.01 0.01 0.24 99.43 rt 181 56.53 17.92 8.38 0.14 3.98 7.17 3.33 0.56 0.65 0.15 0.01 1.48 100.29 rt 182 56.72 17.82 8.36 0.14 3.97 7.24 3.38 0.56 0.65 0.16 0.01 1.48 100.48 Rithmah Complex rt 183 57.19 17.77 8.16 0.13 3.86 7.24 3.40 0.52 0.64 0.16 0.01 1.39 100.47 rt 185 54.11 17.53 9.15 0.14 4.76 7.39 3.07 0.86 0.67 0.14 0.01 2.62 100.45 js 200 73.61 13.84 2.17 0.07 0.53 2.02 4.46 2.08 0.21 0.07 0.01 0.42 99.48 js 201 73.26 14.10 2.32 0.07 0.58 2.43 4.55 1.67 0.23 0.08 0.01 0.51 99.82 Jar-Salajah Complex js 202 72.78 14.53 2.26 0.07 0.53 2.00 4.85 1.89 0.23 0.07 0.01 0.47 99.68 js 203 74.94 13.52 1.82 0.06 0.43 1.53 4.54 2.24 0.19 0.06 0.00 0.25 99.57 sf 208 77.23 12.34 1.02 0.03 0.17 0.60 4.43 3.10 0.10 0.02 0.01 0.36 99.41 sf 209 75.35 12.98 1.41 0.03 0.13 0.16 4.40 4.06 0.12 0.01 0.01 0.63 99.27 Subh Suite sf 211 75.42 12.89 1.41 0.03 0.13 0.41 4.24 4.41 0.11 0.01 0.01 0.37 99.44 sf 213 57.95 16.15 7.44 0.14 3.42 6.34 3.63 1.68 0.80 0.20 0.02 1.93 99.69
448 Table 1 (continued): Arabian Shield samples analysed for major elements by X-Ray Fluorescence (XRF). These analyses were preformed on a Philips PW 1480 X-ray Fluorescence Spectrometer using an analysis program calibrated against several international (BHVO-1and BCR-1) and local (TASBAS) standard reference materials. The analysis method is described in Appendix a3. A complementary sample catalogue is displayed in Appendix 1.
Sample Map Unit SiO2 % Al2O3 % Fe2O3T % MnO % MgO % CaO % Na2O % K2O % TiO2 % P2O5 % SO3 % LOI % Total %
si 114 72.59 13.54 1.93 0.06 0.35 0.60 3.63 5.39 0.29 0.05 0.02 1.02 99.46 Siham Group si 116 74.72 13.11 1.26 0.05 0.19 0.67 3.62 5.11 0.15 0.02 0.01 0.39 99.29 su 214 65.08 15.76 4.59 0.07 1.99 4.01 4.06 2.18 0.62 0.16 0.01 1.16 99.68 su 215 Shufayyah Complex 65.44 15.65 4.41 0.07 1.89 4.07 4.14 2.22 0.59 0.16 0.01 1.13 99.77 su 216 64.98 15.96 4.47 0.07 1.88 4.04 4.14 2.23 0.60 0.16 0.01 1.22 99.76 tfv 02 At Ta'if Group 42.21 11.43 11.49 0.19 19.80 7.47 0.59 0.51 0.63 0.16 0.02 4.92 99.41 VG 198 Admar Suite 75.77 12.75 0.73 0.02 0.11 0.61 3.90 4.80 0.10 0.01 0.03 0.75 99.57 wb 61 71.55 13.04 3.75 0.09 0.12 1.00 3.71 5.64 0.31 0.04 0.01 0.37 99.63 wb 62 71.47 13.17 3.85 0.09 0.13 1.03 3.73 5.65 0.31 0.04 0.02 0.35 99.83 Wadbah Suite wb 63 71.58 13.14 3.48 0.08 0.13 0.93 3.69 5.66 0.27 0.03 0.01 0.55 99.55 wb 65 72.65 12.98 3.07 0.07 0.12 0.84 3.69 5.65 0.25 0.03 0.01 0.37 99.73 154(d) Abanat Suite 76.28 12.03 1.43 0.02 0.16 0.38 4.33 3.74 0.07 0.00 0.02 0.67 99.13
449 Table 2: Arabian Shield samples analysed for trace elements by X-Ray Fluorescence (XRF). These analyses were preformed on a Philips PW 1480 X-ray Fluorescence Spectrometer using an analysis program calibrated against several international (BHVO-1and BCR-1) and local (TASBAS) standard reference materials. Negative values are displayed as 0 and element concentrations >10ppm are rounded to the nearest whole number. This statistical process together with the analytical method is described in Appendix a3.
Zr Nb Y Sr Rb U Th Pb Ga Zn Cu Ni Ba Sc Co V Ce Nd La Cr SAMPLE Map Unit ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm aa 166 589 68 64 9.9 148 5.4 13 20 34 134 1.0 0.0 23 0.5 117 1.0 292 127 155 1.0 aa 167 Admar Suite 627 69 69 9.3 147 4.8 16 20 31 129 24 0.0 26 1.5 133 2.0 273 124 143 1.0 aa 168 1097 77 81 5.1 141 7.6 18 23 28 136 1.0 0.0 23 1.5 127 4.0 247 114 127 2.0 abg 171 115 54 40 13 333 21 37 32 25 26 0.0 0.0 55 4.0 111 3.0 30 8.0 12 2.0 abg 172 110 44 37 9.2 299 7.1 31 29 25 79 0.0 0.0 22 2.9 111 4.0 31 9.0 12 2.0 abg 172 Al Bad Granite 163 26 35 10.4 151 3.4 19 18 18 32 3.0 0.0 30 2.1 134 5.0 52 15 22 2.0 abg 173 Super Suite 116 42 33 8.3 301 5.9 32 29 25 64 3.0 0.0 20 3.0 104 2.0 31 10 13 2.0 abg 179 194 23 45 9.3 159 6.1 18 17 19 22 0.0 0.0 38 2.7 119 5.0 59 25 26 1.0 abg 180 186 24 41 8.7 160 10 17 16 19 24 4.0 0.0 43 2.2 130 4.0 56 24 24 2.0 ad 194 907 6.8 12 894 41 1.6 0.6 16 16 49 3.0 2.0 2936 8.3 39 44 81 33 45 2.0 ad 195 858 8.1 10 900 41 1.0 2.2 17 17 46 2.0 2.0 2981 8.3 48 42 103 40 55 0.0 Admar Suite ad 196 911 6.2 11 884 41 1.5 1.7 16 16 51 2.0 1.0 2886 8.6 56 47 91 37 49 2.0 ad 197 797 7.3 12 900 41 2.8 1.7 18 16 48 6.0 2.0 2910 7.1 37 47 108 41 56 3.0 ao 101 104 4.3 3.3 620 70 2.4 7.2 18 21 28 11 10 723 4.5 76 21 30 9.0 13 51 ao 83 98 8.5 14 45 177 5.3 22 25 13 14 15 0.0 170 2.0 123 5.0 48 14 26 2.0 ao 85 102 7.6 15 44 179 6.2 26 24 15 13 1.0 0.0 159 1.7 115 5.0 51 15 27 1.0 Al Hafoor Suite ao 87 37 2.5 12 453 16 0.5 1.3 6.3 18 75 24 75 248 38 62 227 14 11 5.0 321 ao 88 35 1.8 10 455 16 2.6 1.4 4.4 19 78 9.0 70 228 36 55 218 17 10 5.0 292 ao 98 106 5.0 3.3 609 70 2.3 5.9 17 21 28 9.0 9.0 708 4.9 74 21 28 12 13 50 ay 186 132 2.5 18 198 18 0.0 0.4 5.6 15 60 33 36 291 14 41 99 21 11 7.0 52 ay 187 Al Ays Group 130 3.9 20 236 13 0.0 1.9 4.8 15 67 26 42 177 16 42 113 19 15 6.0 60 ay 206 82 4.0 25 440 9.1 0.7 0.6 1.3 17 86 44 30 248 44 59 293 13 16 6.0 140 CV 192 Mardabah 567 79 53 506 29 1.2 1.3 7.3 25 118 0 1.0 1450 11 39 6.0 146 66 70 0.0 CV 193 Complex 584 79 54 503 28 1.4 1.8 5.9 26 117 10 0.0 1449 11 55 5.0 149 71 72 0.0 dm 01a 110 5.6 30 826 40 1.3 0.9 2.2 19 119 12 50 672 26 62 219 35 25 12 109 dm 01b Makkah Suite 97 2.2 32 373 22 1.6 0.2 5.9 18 86 38 55 323 32 58 220 20 18 7.0 66 dm 01c 336 7.8 50 447 40 1.1 2.0 4.9 19 59 5.0 2.0 1268 13 81 48 47 26 15 3.0 hla 109 242 6.9 18 256 124 4.5 7.5 19 17 32 10 2.0 1305 6.7 87 20 39 15 18 6.0 hla 110 277 7.0 19 248 125 8.1 11 17 17 31 1.0 2.0 1280 6.7 74 20 60 20 29 4.0 Haml Suite hla 111 194 6.3 14 221 128 4.4 11 18 15 26 13 1.0 1107 5.8 86 19 38 12 17 5.0 hla 112 193 6.6 18 220 123 6.8 10 13 14 27 2.0 2.0 1090 6.9 84 18 50 18 22 6.0
450 Table 2 (continued): Arabian Shield samples analysed for trace elements by X-Ray Fluorescence (XRF). These analyses were preformed on a Philips PW 1480 X-ray Fluorescence Spectrometer using an analysis program calibrated against several international (BHVO-1and BCR-1) and local (TASBAS) standard reference materials. Negative values are displayed as 0 and element concentrations >10ppm are rounded to the nearest whole number. This statistical process together with the analytical method is described in Appendix a3.
Zr Nb Y Sr Rb U Th Pb Ga Zn Cu Ni Ba Sc Co V Ce Nd La Cr SAMPLE Map Unit ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm hn 160 238 8.9 29 265 65 2.3 5.2 13 19 58 1.0 0.0 727 9.1 75 19 52 28 24 1.0 Hadn Formation hn 162 995 70 107 2.1 164 12 23 31 33 196 0.0 0.0 6 0.8 73 2.0 228 111 103 2.0 hwg 03 83 59 45 29 204 12 18 26 23 8 32 0.0 72 1.7 114 8.0 18 8.0 4.0 0.0 hwg 04 483 36 59 198 211 4.5 5.8 19 23 145 125 6.0 405 7.4 66 60 102 48 49 11 Al Hawiyah Suite hwg 07 256 28 46 181 200 7.1 21 21 21 62 23 0.0 860 2.6 83 20 115 47 57 1.0 hwg 08 216 35 41 107 174 5.1 13 20 24 52 10 0.0 400 2.9 100 9.0 69 34 28 1.0 hwg 09 236 40 42 115 166 6.3 15 22 22 50 9.0 0.0 460 2.2 107 7.0 78 36 33 1.0 id 155 145 13 26 34 149 7.3 19 21 18 27 6.0 0.0 263 2.9 102 5.0 59 23 27 1.0 id 156 140 18 25 33 140 9.0 18 21 18 32 0.0 0.0 268 3.3 101 4.0 84 32 40 1.0 id 159 Idah Suite 164 14 27 33 136 13 20 20 17 36 6.0 0.0 237 2.7 116 4.0 58 22 27 1.0 id 163 101 11 25 5.0 156 7.1 18 25 18 36 0.0 0.0 26 3.0 105 3.0 30 17 10 1.0 id 164 99 11 23 5.2 154 6.6 17 27 20 35 0.0 0.0 24 3.0 101 3.0 33 16 10 0.0 ih 66 498 14 33 83 74 0.7 5.7 19 19 53 11 0.0 312 4.3 108 8.0 167 79 77 2.0 ih 68 496 15 30 44 61 2.0 6.4 17 20 54 10 0.0 178 4.1 109 4.0 284 115 140 1.0 ih 73 208 6.3 12 232 158 6.4 17 19 19 32 3.0 0.0 761 3.5 97 19 59 19 27 2.0 Ibn Hashbal Suite ih 74 190 5.9 10 233 161 5.3 18 21 19 33 17 0.0 750 3.3 90 20 64 21 32 2.0 ih 76 195 7.4 12 228 176 6.6 18 19 20 36 10 0.0 746 3.5 97 19 61 23 31 2.0 ih 79 199 5.9 10 229 162 3.5 16 18 20 31 2.0 0.0 778 3.5 102 18 63 22 32 3.0 kg 142 68 2.0 48 179 75 3.1 2.8 32 15 0.0 8.0 0.0 490 7.0 124 3.0 4.0 0.0 1.0 1.0 kg 145 64 1.1 14 201 98 1.5 1.9 37 13 0.0 0.0 0.0 627 2.7 120 3.0 8.0 0.0 1.0 1.0 kg 146 Malik Granite 87 1.0 13 196 84 2.5 3.8 32 13 0.0 8.0 0.0 577 1.6 130 3.0 11 4.0 1.0 0.0 kg 148 54 8.8 12 115 168 2.4 11 36 21 20 1.0 0.0 446 3.1 104 5.0 28 11 11 1.0 kg 150 102 11 17 102 165 4.4 26 32 18 32 12 0.0 337 3.9 84 5.0 59 23 24 1.0 ku 121 102 34 204 5.5 241 10 22 29 30 40 4.0 1.0 18 10 113 4.0 58 46 20 6.0 ku 122 104 34 227 4.8 231 7.6 24 30 29 38 11 0.0 17 10 104 4.0 61 49 19 1.0 Ar Ruwaydah Suite ku 123 117 41 214 4.3 237 8.8 25 30 29 48 2.0 0.0 21 11 116 3.0 70 51 21 2.0 ku 139 88 1.4 5.6 296 88 4.8 20 28 15 7.0 4.0 2.0 632 2.0 88 8.0 37 12 18 9.0 kw 10 57 1.3 9.4 206 2.9 0.8 0.9 0.0 13 49 24 37 206 26 73 149 6.0 4.0 2.0 96 kw 11 32 0.7 12 219 2.9 0.0 0.0 1.9 13 52 42 45 183 32 69 181 11 6.0 1.0 122 kw 13 Kawr Suite 507 38 66 5.8 92 3.7 7.2 13 28 106 7.0 0.0 49 1.8 92 2.0 120 63 51 2.0 kw 14 4.2 0.0 0.3 429 2.0 1.0 0.8 1.6 10 22 78 323 48 8.4 56 17 1.0 0.0 0.0 161 kw 15 5.2 1.3 0.0 430 2.7 0.0 0.2 1.9 13 17 23 197 85 7.2 48 12 5.0 0.0 0.0 45
451 Table 2 (continued): Arabian Shield samples analysed for trace elements by X-Ray Fluorescence (XRF). These analyses were preformed on a Philips PW 1480 X-ray Fluorescence Spectrometer using an analysis program calibrated against several international (BHVO-1and BCR-1) and local (TASBAS) standard reference materials. Negative values are displayed as 0 and element concentrations >10ppm are rounded to the nearest whole number. This statistical process together with the analytical method is described in Appendix a3.
Zr Nb Y Sr Rb U Th Pb Ga Zn Cu Ni Ba Sc Co V Ce Nd La Cr SAMPLE Map Unit ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm kw 16 5.7 0.1 0.0 439 6.0 1.2 0.2 1.6 15 15 106 226 28 6.4 46 14 3.0 0.0 9.0 76 kw 18 7.0 0.0 0.0 386 1.5 0.0 0.5 0.0 13 23 106 452 196 8.0 66 13 2.0 0.0 0.0 79 kw 19 6.2 0.5 0.6 338 0.5 0.0 1.7 0.7 13 24 105 341 8 10 74 23 4.0 9.0 0.0 222 kw 21 520 38 68 5.8 99 3.6 7.9 12 29 114 0.0 0.0 46 0.9 92 1.0 146 77 66 1.0 kw 22 529 42 71 5.3 105 3.4 8.8 16 29 123 0.0 0.0 48 0.9 87 3.0 148 75 65 1.0 kw 23 512 37 67 5.2 104 3.7 5.9 14 29 117 1.0 0.0 40 1.7 86 2.0 146 76 63 0.0 kw 24 822 52 100 3.7 96 5.6 12 18 30 128 14 0.0 30 1.1 100 2.0 227 114 108 1.0 kw 29 251 28 73 33 152 6.4 18 16 24 21 9.0 0.0 180 2.7 107 6.0 127 55 58 2.0 kw 30b 156 21 56 258 105 6.5 10 14 21 100 7.0 22 264 18 59 144 70 42 29 77 kw 30p 206 25 54 85 137 10 21 23 22 32 7.0 2.0 234 2.8 128 18 106 42 47 6.0 kw 31 221 26 65 35 148 7.1 18 11 22 18 15 0.0 174 2.3 113 5.0 111 47 49 2.0 kw 32 187 18 46 298 98 2.2 7.5 8.8 22 109 13 26 276 23 51 177 70 41 29 96 kw 33 185 19 48 269 98 4.2 7.5 6.9 20 94 9.0 23 259 19 58 151 71 38 31 88 kw 35 249 27 63 112 118 6.2 17 12 24 55 4.0 10 238 7.5 92 52 110 48 49 26 kw 36 Kawr Suire 274 30 72 53 138 8.7 22 16 23 21 0.0 1.0 241 3.2 105 12 112 48 50 4.0 kw 38 462 36 98 26 142 6.4 15 23 25 96 9.0 0.0 134 2.5 106 7.0 150 74 67 2.0 kw 40 242 8.8 18 20 103 4.0 9 14 18 18 12 0.0 87 1.2 110 3.0 22 12 7.0 1.0 kw 41 229 13 44 93 89 4.7 16 21 19 15 0.0 0.0 356 3.6 112 10 98 41 46 2.0 kw 42 296 30 79 97 97 11 12 8.8 24 97 21 5.0 151 18 65 53 165 102 66 17 kw 43 152 10 37 235 0.8 3.7 6.0 8.6 20 112 12 50 91 23 65 150 54 29 23 94 kw 44 180 14 22 206 118 5.5 16 13 21 35 5.0 0.0 688 3.9 89 12 84 30 41 3.0 kw 45 183 13 24 238 116 5.9 17 16 21 35 5.0 0.0 749 4.1 104 12 50 23 22 3.0 kw 46 248 29 70 36 153 6.0 22 11 21 19 3.0 0.0 198 2.9 98 8.0 129 53 59 2.0 kw 50 188 10 18 279 103 4.9 13 13 20 52 2.0 0.0 876 3.6 111 14 79 30 40 3.0 kw 51b 141 9.1 16 238 95 3.1 10 17 20 34 1.0 1.0 756 2.7 86 14 85 34 42 3.0 kw 51p 143 8.6 12 47 110 2.5 4.5 18 19 17 0.0 0.0 171 1.8 97 4.0 51 19 21 0.0 kw 52b 162 10 16 224 98 4.6 12 16 21 38 1.0 0.0 751 4.4 90 13 95 38 47 2.0 kw 52p 164 9.1 12 55 111 2.8 3.4 19 18 17 1.0 0.0 198 1.0 110 6.0 39 16 17 0.0 kw 55 164 12 42 276 2.1 3.2 5.6 6.5 19 95 102 51 177 24 64 155 50 33 22 102 ky 124 Al Khushaymiyah 91 3.3 1.0 552 93 2.2 4.8 27 25 41 1.0 0.0 851 2.2 64 7.0 24 12 9.0 1.0 ky 125 Suite 94 4.1 1.5 526 91 2.1 5.1 28 26 42 2.0 0.0 740 2.3 52 7.0 24 8.0 8.0 1.0
452 Table 2 (continued): Arabian Shield samples analysed for trace elements by X-Ray Fluorescence (XRF). These analyses were preformed on a Philips PW 1480 X-ray Fluorescence Spectrometer using an analysis program calibrated against several international (BHVO-1and BCR-1) and local (TASBAS) standard reference materials. Negative values are displayed as 0 and element concentrations >10ppm are rounded to the nearest whole number. This statistical process together with the analytical method is described in Appendix a3.
Zr Nb Y Sr Rb U Th Pb Ga Zn Cu Ni Ba Sc Co V Ce Nd La Cr SAMPLE Map Unit ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ky 126 Al Khushaymiyah 98 3.4 2.0 516 90 3.4 6.5 27 26 41 2.0 0.0 720 2.0 42 7.0 24 9.0 10 2.0 ky 129 694 4.8 10 673 107 4.8 16 22 18 32 0.0 2.0 1982 2.2 71 29 35 10 20 4.0 ky 130 Suite 803 4.7 9.1 687 107 3.7 18 22 18 35 0.0 2.0 1907 3.3 58 32 35 8.0 21 5.0 MCR 104 73 3.1 17 405 48 0.2 1.2 4.2 17 112 22 160 418 29 58 238 28 15 8.0 421 Bani Ghayy Group MCR 105 68 2.4 17 567 21 1.3 1.1 7.7 17 80 2.0 73 354 30 60 241 15 14 6.0 224 MD 93 102 3.3 2.5 1030 69 3.1 3.7 19 19 32 2.0 2.0 994 4.0 70 28 31 11 12 11 Al Hafoor Suite MD 95 105 2.5 2.2 1024 69 2.8 5.4 21 19 31 2.0 2.0 989 3.2 73 28 28 11 13 11 mr 188 182 70 30 613 50 3.0 10 3.8 20 75 1.0 0.0 2706 7.3 30 6.0 107 43 56 0.0 mr 189 314 64 32 625 45 3.2 5.8 4.2 22 68 1.0 0.0 2656 6.6 33 7.0 102 44 51 0.0 Mardabah Complex mr 190 1116 59 32 594 41 3.0 4.2 3.3 22 65 13 1.0 2220 7.3 30 5.0 106 42 52 0.0 mr 191 236 56 29 571 41 1.2 4.3 5.4 22 71 10 0.0 2185 7.0 55 8.0 90 39 46 0.0 mu 131 183 9.2 19 817 60 2.6 4.6 8.3 22 87 28 57 892 17 54 194 54 32 23 110 mv 132 183 8.5 16 886 60 2.3 4.9 9.1 21 82 43 50 1453 16 43 176 57 30 22 111 Murdama Group mu 134 253 7.4 23 162 104 3.4 6.6 3.4 18 62 77 3.0 1031 6.2 57 61 68 32 32 5.0 mv 135 253 8.4 22 143 106 2.0 8.7 19 17 37 172 2.0 624 7.0 41 53 72 31 32 3.0 nr 117 164 15 83 56 185 4.7 16 29 23 30 1.0 0.0 320 7.1 117 11 87 49 33 3.0 nr 119 177 16 94 55 182 4.1 18 28 23 28 1.0 1.0 336 6.1 119 7.0 101 54 39 2.0 Najirah Granite nr 120 172 15 93 58 182 5.4 18 27 23 27 22 0.0 369 5.6 102 9.0 92 52 36 3.0 nr 136 383 6.1 51 151 111 2.3 16 27 16 39 29 0.0 185 0.5 108 5.0 166 76 77 0.0 rt 181 59 2.4 15 364 11 0.2 1.5 2.5 20 80 39 17 154 24 51 175 14 12 3.0 41 rt 182 58 3.3 16 367 11 0.5 2.1 0.1 19 78 41 18 117 23 43 181 11 14 3.0 42 Rithmah Complex rt 183 62 2.2 15 356 10 1.4 0.0 4.0 18 76 44 18 94 23 55 174 17 11 2.0 39 rt 185 51 2.7 14 338 16 0.4 0.8 2.8 19 78 49 20 149 29 44 225 15 14 3.0 38 js 200 144 4.5 24 193 31 2.0 3.5 7.1 17 37 10 0.0 348 5.8 99 14 35 13 12 2.0 js 201 128 4.7 18 231 27 0.4 4.2 4.0 16 40 12 0.0 410 6.1 105 15 31 14 12 1.0 Jar-Salajah Complex js 202 131 3.1 22 208 26 0.9 3.6 8.9 15 41 0.0 0.0 403 5.8 87 13 33 15 14 2.0 js 203 145 3.7 23 161 31 1.3 3.7 6.0 14 33 1.0 0.0 430 4.6 98 12 40 18 17 0.0 sf 208 89 3.6 19 76 39 1.2 3.9 11 13 17 4.0 0.0 813 2.9 115 6.0 39 15 16 2.0 sf 209 205 8.5 54 33 67 4.5 7.2 2.7 18 25 7.0 0.0 689 6.1 109 4.0 56 27 21 1.0 Subh Suite sf 211 221 9.4 58 30 96 5.1 6.7 12 17 41 7.0 0.0 791 5.9 116 3.0 61 30 23 1.0 sf 213 145 3.9 30 307 30 2.3 2.1 0.9 16 75 16 6.0 406 22 50 136 31 21 11 52
453 Table 2 (continued): Arabian Shield samples analysed for trace elements by X-Ray Fluorescence (XRF). These analyses were preformed on a Philips PW 1480 X-ray Fluorescence Spectrometer using an analysis program calibrated against several international (BHVO-1and BCR-1) and local (TASBAS) standard reference materials. Negative values are displayed as 0 and element concentrations >10ppm are rounded to the nearest whole number. This statistical process together with the analytical method is described in Appendix a3.
Zr Nb Y Sr Rb U Th Pb Ga Zn Cu Ni Ba Sc Co V Ce Nd La Cr SAMPLE Map Unit ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm si 114 363 35 45 97 185 5.7 20 21 20 74 4.0 0.0 1020 4.8 64 7.0 166 68 72 1.0 Siham Group si 116 186 31 42 71 204 7.6 27 42 22 39 0.0 0.0 402 3.4 88 4.0 138 55 62 0.0 su 214 Shufayyah 168 3.9 25 349 41 0.1 0.9 6.1 18 44 6.0 10 459 13 68 75 30 19 10 32 su 215 165 4.7 25 343 41 1.9 1.9 6.0 16 42 4.0 1.0 476 13 66 70 30 16 11 24 su 216 Complex 166 4.5 25 351 43 0.8 4.5 5.9 16 44 5.0 17 469 13 78 74 30 16 12 57 tfv 02 At Ta'if Group 33 6.5 12 22 11 0.0 0.8 2.0 14 77 46 771 78 33 81 193 26 19 10 1673 VG 198 Admar Suite 92 8.6 10 124 60 5.4 14 16 17 5 14 0.0 495 2.1 86 5.0 55 18 25 0.0 wb 61 839 20 39 26 63 2.8 4.1 14 25 129 2.0 0.0 305 3.6 74 5.0 122 69 53 1.0 wb 63 730 19 37 20 64 4.8 6.4 14 24 122 23 0.0 265 3.7 80 5.0 131 74 58 2.0 Wadbah Suite wb 65 630 16 31 22 63 3.2 5.8 14 21 108 12 0.0 318 3.3 103 3.0 133 72 63 2.0 wb 62 793 21 40 25 61 2.6 5.4 17 25 131 10 0.0 295 3.5 69 4.0 131 73 57 1.0 154(d) Abanat Suite 521 160 132 4.5 199 15 22 107 35 136 27 0.0 10 0.8 98 2.0 72 32 32 0.0
454 Table 3: Arabian Shield samples analysed for Rare Earth Elements (REE) using Solution-Inductively Coupled Mass Spectrometry (ICPMS). These analyses were preformed on an Agilent 7500 Spectrometer and were fitted to a calibration curve using a series of multi-element standards of known concentration. Corrections were conducted using an Indium-Rhenium standard solution. International standards G2, GSP2 and BCR2 were analysed routinely for instrument and data reliability (see below). This process is described in detail in Appendix a4.
Be Cs Dy Eu Hf Sm Yb Er Gd Ho Lu Pr Ta Tb Mo Sample Map Unit ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm aa 166 6.04 2.09 11.07 1.02 16.90 21.87 6.00 5.96 17.47 2.15 0.90 41.95 1.96 2.16 1.93 aa 167 Abanat Suite 6.22 2.27 12.58 1.13 17.18 23.94 6.69 6.76 19.39 2.43 0.97 44.42 2.25 2.40 1.68 aa 168 5.57 1.98 12.88 1.01 25.09 20.63 7.77 7.60 17.50 2.63 1.14 35.44 2.25 2.33 1.74 abg 171 5.32 10.84 2.90 0.11 7.63 1.97 5.96 3.13 2.07 0.78 1.06 3.50 2.46 0.40 0.56 abg 172 4.73 8.34 2.44 0.07 6.99 1.54 4.39 2.66 1.70 0.67 0.73 3.27 1.89 0.32 0.73 abg 173 Al Bad Granite Super 4.19 8.76 2.35 0.07 7.25 1.55 4.33 2.61 1.70 0.65 0.71 3.51 1.91 0.32 0.65 abg 178 Suite 3.51 1.97 3.88 0.11 7.05 3.21 4.06 3.10 3.29 0.93 0.62 5.02 0.63 0.58 0.96 abg 179 4.19 2.69 6.03 0.22 7.69 5.95 4.47 4.02 5.86 1.31 0.67 7.43 0.74 0.97 0.94 abg 180 3.47 2.62 5.31 0.19 7.49 5.12 4.21 3.58 4.92 1.18 0.63 6.62 0.71 0.83 0.88 ad 194 0.76 0.48 2.57 3.84 19.28 7.20 1.34 1.36 5.29 0.49 0.24 12.47 0.40 0.57 0.69 ad 195 0.69 0.47 2.63 3.92 17.31 7.87 1.31 1.36 5.76 0.49 0.24 15.14 0.40 0.59 0.74 Admar Suite ad 196 0.66 0.50 2.69 3.85 17.94 7.66 1.35 1.38 5.77 0.52 0.24 13.67 0.45 0.60 0.72 ad 197 0.68 0.50 2.76 3.90 15.84 8.70 1.31 1.37 6.21 0.51 0.23 17.07 0.36 0.63 0.67 ao 83 2.36 7.83 1.95 0.17 3.66 2.82 1.51 1.25 2.45 0.40 0.22 5.13 1.03 0.34 0.78 ao 85 2.38 7.62 1.99 0.16 4.07 2.80 1.56 1.26 2.54 0.43 0.23 5.21 0.95 0.35 0.74 ao 87 2.32 4.00 2.00 0.60 3.12 2.63 1.34 1.28 2.49 0.39 0.23 5.30 0.98 0.35 0.69 Al Hafoor Suite ao 88 0.58 0.57 1.48 0.62 0.98 1.73 0.93 0.90 1.65 0.32 0.13 1.71 0.14 0.25 0.21 ao 98 2.42 2.05 0.73 0.63 3.28 2.25 0.33 0.33 1.65 0.13 0.05 3.45 0.59 0.17 0.34 ao 101 2.42 1.94 0.65 0.61 3.09 2.00 0.30 0.31 1.48 0.12 0.04 3.17 0.58 0.15 0.31 ay 186 0.60 1.19 3.09 0.88 3.09 3.35 1.86 1.84 3.34 0.67 0.27 3.01 0.25 0.52 0.31 ay 187 Al Ays Group 0.71 0.70 3.35 0.85 3.50 3.45 2.03 2.05 3.53 0.73 0.31 2.96 0.29 0.55 0.26 ay 206 0.35 0.17 3.55 1.05 2.02 3.30 1.98 2.07 3.55 0.73 0.29 2.32 0.18 0.58 0.20 CV 192 1.71 0.13 8.63 4.45 12.12 12.26 3.49 4.20 11.29 1.63 0.49 17.32 3.65 1.62 3.79 Mardabah Complex CV 193 1.82 0.15 9.53 4.78 12.70 13.51 3.87 4.57 12.50 1.80 0.54 18.69 3.77 1.75 4.07 dm 01a 1.15 1.30 4.63 1.45 3.44 5.53 2.47 2.64 5.13 0.95 0.35 5.27 0.45 0.79 0.68 dm 01b Makkah Suite 0.62 0.48 4.49 1.22 2.71 3.85 2.65 2.73 4.25 0.96 0.38 2.73 0.24 0.72 0.44 dm 01c 1.27 3.21 7.46 1.89 8.66 7.59 4.05 4.34 7.69 1.56 0.58 6.35 0.66 1.23 0.60 hla 109 1.38 8.68 2.80 0.77 6.63 3.56 1.73 1.68 3.19 0.59 0.27 4.25 0.69 0.48 0.51 hla 110 1.21 8.33 2.81 0.71 7.18 3.89 1.71 1.66 3.44 0.58 0.26 5.78 0.64 0.49 0.49 Haml Suite hla 111 1.20 8.97 2.26 0.63 6.52 2.98 1.47 1.38 2.62 0.47 0.23 3.92 0.63 0.38 0.62 hla 112 1.24 8.21 2.86 0.66 6.07 3.66 1.74 1.73 3.29 0.59 0.26 4.88 0.59 0.48 0.54
455 Table 3 (continued): Arabian Shield samples analysed for Rare Earth Elements (REE) using Solution-Inductively Coupled Mass Spectrometry (ICPMS). These analyses were preformed on an Agilent 7500 Spectrometer and were fitted to a calibration curve using a series of multi-element standards of known concentration. Corrections were conducted using an Indium-Rhenium standard solution. International standards G2, GSP2 and BCR2 were analysed routinely for instrument and data reliability (see below). This process is described in detail in Appendix a4.
Be Cs Dy Eu Hf Sm Yb Er Gd Ho Lu Pr Ta Tb Mo Sample Map Unit ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm hn 160 1.84 1.20 4.93 1.43 6.28 6.37 2.92 2.93 5.81 1.02 0.43 7.84 0.77 0.86 1.54 Hadn Formation hn 162 6.95 1.90 19.11 1.42 26.30 25.03 10.16 10.74 22.67 3.90 1.45 32.33 3.97 3.38 4.42 hwg 03 3.12 2.20 7.28 0.28 4.88 3.72 5.14 4.63 4.76 1.55 0.74 1.88 3.44 1.06 1.75 hwg 04 3.01 3.89 7.69 1.92 11.98 10.90 4.84 4.64 9.25 1.57 0.68 14.03 1.89 1.35 1.87 hwg 07 Al Hawiyah Suite 2.93 4.10 6.34 1.05 7.89 9.11 3.95 3.73 7.81 1.27 0.60 15.31 2.08 1.13 1.14 hwg 08 3.15 3.72 5.88 0.84 6.95 7.26 3.88 3.52 6.45 1.21 0.59 8.61 1.58 1.01 0.77 hwg 09 4.24 3.94 6.85 0.93 8.43 8.36 4.41 4.14 7.53 1.41 0.66 9.93 1.94 1.18 0.85 id 155 2.61 8.14 3.97 0.26 5.72 5.26 2.72 2.40 4.55 0.82 0.40 7.57 1.46 0.68 0.71 id 156 1.81 5.83 3.63 0.25 5.45 4.51 2.49 2.22 3.90 0.75 0.37 6.15 1.06 0.60 1.15 id 159 Idah Suite 1.80 5.71 3.79 0.24 6.41 4.81 2.65 2.32 4.22 0.79 0.39 6.87 1.03 0.65 1.07 id 163 2.61 7.38 3.72 0.07 4.65 4.36 2.17 2.07 3.94 0.74 0.31 4.04 0.94 0.63 0.91 id 164 2.67 8.14 3.54 0.07 4.11 4.50 1.96 1.92 3.94 0.69 0.28 4.54 0.79 0.62 0.88 ih 66 1.47 1.23 5.96 1.18 9.86 13.54 2.83 3.12 10.16 1.15 0.37 27.10 0.88 1.21 1.16 ih 68 1.11 0.99 6.81 1.28 9.90 19.79 2.43 3.11 14.61 1.21 0.33 45.43 0.57 1.53 2.27 ih 73 1.62 5.58 1.92 0.77 5.94 3.76 0.98 0.97 3.12 0.36 0.15 6.33 0.81 0.40 0.49 Ibn Hashbal Suite ih 74 1.33 3.78 1.42 0.63 4.60 3.17 0.73 0.71 2.54 0.26 0.11 5.70 0.66 0.29 0.49 ih 76 1.92 5.13 2.08 0.75 5.45 3.73 1.18 1.10 3.23 0.40 0.17 6.45 1.01 0.40 0.45 ih 79 1.60 5.20 1.75 0.70 5.47 3.68 0.85 0.89 3.01 0.33 0.12 6.46 0.80 0.36 0.46 kg 142 0.98 8.12 2.05 0.49 3.62 0.51 2.70 3.45 1.17 1.64 1.75 0.42 0.33 0.46 0.45 kg 145 1.36 5.67 1.61 0.67 2.82 0.70 3.89 2.01 0.77 0.49 0.71 0.66 0.35 0.18 0.50 kg 146 Malik Granite 1.40 4.95 1.59 0.64 3.84 1.24 3.38 1.78 1.16 0.45 0.61 1.23 0.37 0.21 0.50 kg 148 2.29 8.62 1.84 0.37 2.00 3.05 0.85 0.91 2.47 0.34 0.12 3.73 1.19 0.37 0.51 kg 150 2.36 6.64 3.20 0.38 3.98 6.55 1.33 1.44 5.14 0.56 0.18 8.24 1.17 0.68 0.43 ku 121 5.49 9.18 32.63 0.07 5.61 20.28 16.05 18.61 25.69 6.79 2.11 10.11 1.03 5.13 0.53 ku 122 5.25 8.23 36.32 0.06 6.13 21.83 18.24 20.95 28.35 7.66 2.41 10.38 1.21 5.70 0.49 Ar Ruwaydah Suite ku 123 5.33 8.84 35.55 0.07 6.67 22.75 17.76 20.39 28.56 7.47 2.33 11.45 1.03 5.69 0.50 ku 139 1.10 1.09 0.97 0.48 3.11 2.93 0.46 0.45 2.18 0.17 0.07 4.15 0.28 0.23 0.41 kw 10 0.27 0.65 1.51 0.45 1.46 1.27 1.05 0.95 1.38 0.33 0.16 1.11 0.35 0.24 0.00 kw 11 0.28 0.05 1.76 0.51 1.03 1.46 1.11 1.07 1.61 0.37 0.17 1.19 0.26 0.28 0.00 kw 13 Kawr Suite 2.48 1.09 11.41 1.01 12.87 15.43 6.34 6.34 13.78 2.28 0.95 18.95 1.26 2.04 8.33 kw 14 0.06 0.38 0.15 0.21 0.04 0.19 0.08 0.09 0.17 0.03 0.01 0.12 0.03 0.03 0.04 kw 15 0.06 0.14 0.14 0.23 0.04 0.19 0.08 0.07 0.15 0.03 0.01 0.13 0.05 0.03 0.06
456 Table 3 (continued): Arabian Shield samples analysed for Rare Earth Elements (REE) using Solution-Inductively Coupled Mass Spectrometry (ICPMS). These analyses were preformed on an Agilent 7500 Spectrometer and were fitted to a calibration curve using a series of multi-element standards of known concentration. Corrections were conducted using an Indium-Rhenium standard solution. International standards G2, GSP2 and BCR2 were analysed routinely for instrument and data reliability (see below). This process is described in detail in Appendix a4.
Be Cs Dy Eu Hf Sm Yb Er Gd Ho Lu Pr Ta Tb Mo Sample Map Unit ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm kw 16 0.06 0.67 0.16 0.23 0.05 0.20 0.10 0.10 0.18 0.05 0.03 0.14 0.06 0.04 0.06 kw 18 0.05 0.25 0.11 0.21 0.04 0.15 0.07 0.06 0.14 0.03 0.02 0.13 0.04 0.03 0.13 kw 19 0.06 0.34 0.24 0.23 0.07 0.22 0.13 0.13 0.22 0.05 0.02 0.13 0.15 0.04 0.00 kw 21 2.66 1.29 1.13 0.07 13.25 1.09 0.84 0.69 1.26 0.23 0.14 1.00 2.55 0.18 0.04 kw 22 2.98 1.12 11.34 0.97 12.23 16.03 6.04 6.18 14.12 2.27 0.92 21.80 0.83 2.06 3.90 kw 23 3.04 1.03 11.39 0.97 11.68 16.76 6.20 6.32 14.62 2.31 0.95 22.79 0.44 2.08 4.97 kw 24 3.65 0.75 15.59 1.06 19.92 22.37 8.56 8.81 19.31 3.17 1.25 30.92 1.65 2.81 0.01 kw 29 3.39 2.83 9.71 0.50 8.78 10.90 6.35 6.11 10.00 2.08 0.94 15.92 0.76 1.62 2.54 kw 30b 2.42 3.12 7.83 1.25 5.37 8.15 4.91 4.77 7.87 1.65 0.70 8.93 1.49 1.29 0.02 kw 30p 3.81 3.38 7.91 0.68 9.02 8.86 5.60 5.13 8.19 1.69 0.80 13.03 1.73 1.30 0.02 kw 31 3.31 2.63 8.54 0.47 7.60 9.42 5.64 5.48 8.83 1.84 0.83 13.01 1.16 1.42 1.67 kw 32 1.95 2.61 7.19 1.53 6.04 8.00 4.19 4.20 7.75 1.49 0.61 8.63 1.25 1.22 0.02 kw 33 2.14 2.77 7.43 1.40 6.25 8.12 4.54 4.43 7.80 1.56 0.66 9.23 1.41 1.24 0.01 kw 35 4.14 3.62 8.96 0.84 9.37 9.61 6.23 5.67 9.14 1.91 0.90 12.85 2.41 1.48 0.02 kw 36 Kawr Suite 4.12 3.45 10.05 0.70 10.10 10.63 6.93 6.47 10.03 2.16 1.01 15.35 1.14 1.65 4.62 kw 38 4.36 4.76 14.72 0.83 14.17 15.58 9.09 9.07 15.13 3.13 1.31 20.20 0.86 2.45 1.89 kw 40 1.90 2.15 2.64 0.25 8.76 2.91 1.80 1.63 2.76 0.56 0.28 2.79 0.45 0.45 0.88 kw 41 1.95 2.84 6.89 0.72 6.90 9.06 4.06 3.61 7.93 1.31 0.60 13.74 0.95 1.24 0.81 kw 42 2.97 1.74 15.04 0.50 9.47 22.90 5.22 6.74 19.54 2.77 0.70 23.30 1.59 2.86 0.09 kw 43 1.19 0.01 5.28 1.12 4.01 5.77 3.22 3.18 5.64 1.12 0.48 5.98 0.79 0.89 0.01 kw 44 2.38 2.77 3.42 0.82 5.79 5.83 2.05 1.92 4.69 0.68 0.31 9.54 0.77 0.63 0.00 kw 45 2.79 2.83 3.91 0.86 5.54 6.13 2.21 2.18 5.21 0.78 0.32 9.33 1.09 0.73 0.00 kw 46 3.21 3.20 10.52 0.62 10.31 11.47 7.05 6.66 10.84 2.27 1.01 16.64 1.27 1.77 1.43 kw 50 2.19 3.37 3.06 0.91 5.38 5.22 1.57 1.63 4.37 0.59 0.24 8.67 0.77 0.58 0.00 kw 51b 1.77 2.49 3.12 0.86 4.64 7.08 1.17 1.42 5.51 0.56 0.17 11.58 0.69 0.67 0.01 kw 51p 1.34 2.57 2.27 0.31 5.26 3.61 1.10 1.16 3.01 0.43 0.16 5.61 0.46 0.43 0.01 kw 52b 1.75 1.92 2.93 0.88 3.67 5.96 1.20 1.42 4.72 0.55 0.19 9.72 0.52 0.60 0.68 kw 52p 1.34 1.82 2.08 0.35 5.29 3.13 1.04 1.08 2.79 0.40 0.16 4.77 0.53 0.38 0.85 kw 55 1.42 0.08 5.79 1.22 4.41 6.17 3.51 3.46 6.02 1.22 0.51 6.42 0.89 0.98 0.01 ky 124 2.83 6.75 0.42 0.67 3.34 2.35 0.09 0.11 1.61 0.05 0.01 2.73 0.37 0.14 0.28 Al Khushaymiyah Suite ky 125 2.88 6.42 0.44 0.67 3.54 2.40 0.09 0.11 1.59 0.05 0.01 2.67 0.38 0.15 0.33
457 Table 3 (continued): Arabian Shield samples analysed for Rare Earth Elements (REE) using Solution-Inductively Coupled Mass Spectrometry (ICPMS). These analyses were preformed on an Agilent 7500 Spectrometer and were fitted to a calibration curve using a series of multi-element standards of known concentration. Corrections were conducted using an Indium-Rhenium standard solution. International standards G2, GSP2 and BCR2 were analysed routinely for instrument and data reliability (see below). This process is described in detail in Appendix a4.
Be Cs Dy Eu Hf Sm Yb Er Gd Ho Lu Pr Ta Tb Mo Sample Map Unit ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ky 126 2.99 6.90 0.46 0.70 3.54 2.53 0.09 0.12 1.67 0.05 0.01 2.92 0.33 0.15 0.25 ky 129 Al Khushaymiyah Suite 1.86 8.49 1.57 1.20 17.59 2.58 1.54 1.15 2.15 0.35 0.27 4.16 0.57 0.28 0.91 ky 130 1.92 8.23 1.23 1.12 17.83 2.04 1.38 0.98 1.70 0.29 0.25 3.54 0.43 0.23 0.86 MCR 104 0.45 0.90 2.63 1.12 1.68 3.00 1.39 1.47 3.00 0.53 0.19 2.62 0.16 0.44 0.39 Bani Ghayy Group MCR 105 0.68 0.70 2.75 1.07 1.68 3.10 1.49 1.60 3.02 0.57 0.22 2.75 0.23 0.47 0.45 MD 93 1.54 5.56 0.65 0.65 2.69 2.00 0.28 0.30 1.44 0.11 0.04 3.58 0.46 0.14 0.30 Al Hafoor Suite MD 95 1.39 4.76 0.60 0.58 2.63 1.78 0.24 0.28 1.29 0.11 0.03 3.34 0.43 0.13 0.28 mr 188 2.06 0.73 5.34 5.80 4.51 8.51 2.05 2.49 7.67 0.97 0.29 12.97 4.37 1.04 1.45 mr 189 1.91 0.70 5.76 5.96 6.55 8.85 2.19 2.72 7.99 1.05 0.30 12.50 4.16 1.09 1.69 Mardabah Complex mr 190 1.61 0.63 5.44 5.38 5.62 8.23 2.52 2.76 7.33 1.05 0.37 11.30 3.58 1.02 1.59 mr 191 1.73 0.77 5.37 5.56 5.04 8.05 2.15 2.53 7.38 0.99 0.29 11.03 3.64 1.02 1.68 mu 131 1.16 1.59 3.74 1.95 4.05 7.32 1.50 1.77 5.99 0.68 0.21 8.50 0.55 0.74 0.57 mu 132 1.32 1.43 3.30 1.93 4.37 7.01 1.31 1.53 5.54 0.60 0.19 8.58 0.51 0.69 0.45 Murdama Group mv 134 1.35 1.60 3.82 1.34 6.38 6.10 2.14 2.16 5.31 0.77 0.33 8.97 0.66 0.71 1.09 mv 135 1.79 2.45 3.83 1.28 6.68 6.28 2.18 2.16 5.28 0.78 0.33 9.39 0.63 0.72 1.79 nr 117 3.47 8.50 15.51 0.62 6.61 17.23 8.68 8.74 16.21 3.33 1.07 18.59 1.20 2.81 0.49 nr 119 3.11 8.67 15.09 0.67 6.74 17.09 8.46 8.51 16.03 3.03 1.16 18.41 1.34 2.58 0.54 Najirah Granite nr 120 3.08 8.45 15.93 0.68 6.97 17.31 9.09 9.15 16.20 3.24 1.26 18.32 1.13 2.67 0.48 nr 136 0.67 3.63 10.29 0.44 12.00 16.02 3.68 4.98 13.61 1.93 0.45 25.07 0.80 1.89 0.77 rt 181 0.35 0.45 2.16 0.67 1.57 2.11 1.38 1.32 2.11 0.46 0.21 1.59 0.24 0.34 0.23 rt 182 0.36 0.37 2.27 0.68 1.66 2.16 1.41 1.40 2.24 0.49 0.22 1.67 0.20 0.37 0.24 Rithmah Complex rt 183 0.35 0.43 2.25 0.68 1.72 2.25 1.41 1.39 2.28 0.48 0.21 1.72 0.32 0.37 0.31 rt 185 0.32 0.24 2.07 0.63 1.40 2.00 1.28 1.29 2.06 0.45 0.19 1.50 0.15 0.34 0.12 js 200 1.08 0.79 3.32 0.54 4.58 3.40 2.67 2.24 3.20 0.73 0.41 4.00 0.58 0.52 0.59 js 201 0.95 0.88 2.69 0.70 3.69 3.25 2.10 1.80 2.99 0.59 0.33 4.32 0.62 0.45 0.84 Jar-Salajah Complex js 202 0.92 0.53 3.06 0.62 4.29 3.38 2.48 2.05 3.10 0.68 0.39 4.26 0.57 0.50 0.63 js 203 0.99 0.66 2.97 0.64 3.88 3.36 2.37 1.61 3.07 0.65 0.27 4.25 0.57 0.56 0.59 sf 208 0.95 0.18 3.07 0.49 2.96 4.04 2.56 2.14 3.48 0.69 0.41 5.81 0.68 0.52 0.83 sf 209 1.21 0.47 8.31 0.63 7.46 7.55 6.00 5.53 7.50 1.85 0.90 8.04 0.95 1.30 1.32 Subh Suite sf 211 2.09 0.56 8.97 0.55 7.90 8.09 6.80 6.10 8.07 2.02 1.02 8.82 0.95 1.40 3.18 sf 213 0.75 0.52 4.98 1.24 3.69 4.88 3.21 3.11 5.00 1.08 0.49 4.47 0.36 0.81 1.36
458 Table 3 (continued): Arabian Shield samples analysed for Rare Earth Elements (REE) using Solution-Inductively Coupled Mass Spectrometry (ICPMS). These analyses were preformed on an Agilent 7500 Spectrometer and were fitted to a calibration curve using a series of multi-element standards of known concentration. Corrections were conducted using an Indium-Rhenium standard solution. International standards G2, GSP2 and BCR2 were analysed routinely for instrument and data reliability (see below). This process is described in detail in Appendix a4.
Be Cs Dy Eu Hf Sm Yb Er Gd Ho Lu Pr Ta Tb Mo Sample Map Unit ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm si 114 3.40 2.21 7.97 2.19 10.06 13.97 4.41 4.42 11.13 1.56 0.64 21.23 2.27 1.48 0.80 Siham Group si 116 5.74 3.22 7.00 1.18 6.65 11.44 4.38 4.10 9.21 1.42 0.63 18.17 2.54 1.30 4.80 su 214 0.84 0.92 4.20 1.04 4.69 4.55 2.67 2.59 4.39 0.90 0.40 4.51 0.48 0.70 0.83 su 215 Shufayyah Complex 0.95 1.07 4.01 0.97 4.90 4.40 2.61 2.50 4.28 0.86 0.40 4.49 0.47 0.67 0.65 su 216 1.02 0.86 4.12 1.05 4.59 4.60 2.69 2.62 4.35 0.90 0.40 4.60 0.53 0.70 0.59 tfv 02 At Ta'if Group 0.38 0.43 2.13 0.73 0.56 2.68 1.19 1.25 2.44 0.45 0.17 3.16 0.23 0.36 0.08 VG 198 Admar Suite 1.46 0.59 1.74 0.54 3.25 3.74 0.99 0.96 2.77 0.34 0.15 7.01 0.89 0.33 0.77 wb 61 1.69 3.37 7.32 3.05 19.30 13.93 3.76 3.78 11.17 1.39 0.60 20.57 1.08 1.44 2.70 wb 62 1.82 3.30 7.70 3.05 19.29 14.97 3.94 3.93 11.91 1.46 0.60 22.68 1.06 1.52 2.65 Wadbah Suite wb 63 1.77 3.45 7.11 2.94 18.31 14.21 3.65 3.57 11.19 1.33 0.56 22.47 0.99 1.40 2.12 wb 65 1.51 2.81 5.77 2.82 14.88 13.10 2.92 2.92 9.95 1.07 0.46 22.25 1.03 1.18 2.35 154(d) Abanat Suite 6.45 1.43 15.64 0.07 27.89 9.46 11.39 10.74 10.93 3.53 1.53 9.19 6.71 2.27 5.78
459 Table 3 (continued): International standard reference materials analysed for Rare Earth Elements (REE) using Solution-Inductively Coupled Mass Spectrometry (ICPMS). These analyses were preformed on an Agilent 7500 Spectrometer in conjunction with the above unknown Saudi Arabian samples. The standards are all individual powdered samples prepared in a similar fashion and were analysed at random to gauge instrument and data reliability. Elements such as Hf and Zr (zircon) are used as a benchmark for complete dissolution of the powders. Both standards and unknown samples were cross-checked with XRF data, thus confirming the reliability of REE for unknown samples. This process is described in detail in Appendix a4.
Be Cs Dy Eu Hf Sm Yb Er Gd Ho Lu Pr Ta Tb Mo Sample ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm G2 1.87 1.80 2.11 1.47 7.40 7.16 0.76 0.94 4.97 0.36 0.11 16.92 0.78 0.50 0.23 G2 1.88 1.78 2.10 1.43 7.36 7.07 0.73 0.92 5.03 0.37 0.10 17.13 0.76 0.49 0.21 G2 1.87 2.09 2.25 1.50 8.08 7.60 0.82 1.00 5.39 0.39 0.11 17.32 0.85 0.54 0.00 GSP2 1.10 1.48 5.88 2.30 14.94 27.10 1.81 2.62 16.46 1.01 0.25 55.32 0.89 1.52 2.46 GSP2 1.11 1.82 5.96 2.28 14.92 26.98 1.80 2.59 16.33 1.00 0.25 54.99 0.89 1.53 0.01 GSP2 1.13 1.69 5.92 2.38 13.88 27.55 1.81 2.61 16.37 1.01 0.26 58.84 0.88 1.54 2.05 GSP2 1.01 1.44 5.50 2.19 13.28 25.45 1.65 2.42 15.05 0.93 0.23 54.13 0.82 1.42 1.87 GSP2 1.25 1.22 5.77 2.25 14.75 26.98 1.77 2.59 16.04 1.00 0.26 54.28 0.89 1.49 2.19 GSP2 1.16 2.11 6.20 2.39 15.45 28.45 1.88 2.66 16.84 1.04 0.26 57.85 0.97 1.58 2.08 GSP2 1.32 2.34 5.64 2.15 15.54 25.84 1.70 2.46 15.70 0.95 0.23 57.15 0.87 1.43 1.96 GSP2 1.15 2.80 6.04 2.33 15.25 27.76 1.87 2.66 16.40 1.03 0.26 61.58 0.91 1.56 1.98 GSP2 1.19 2.60 5.88 2.24 15.66 27.08 1.79 2.57 16.04 0.99 0.25 59.09 0.89 1.48 2.27 GSP2 1.25 2.20 6.21 2.38 14.42 28.16 1.88 2.69 17.10 1.04 0.26 62.12 0.90 1.57 2.02 BCR2 1.62 1.16 6.18 1.89 4.52 6.58 3.44 3.57 6.77 1.31 0.51 6.79 0.76 1.07 224.79 BCR2 1.52 0.62 5.19 1.69 4.21 5.44 2.65 3.05 5.85 1.05 0.38 5.79 0.67 0.88 229.90 BCR2 1.42 0.74 5.16 1.64 4.14 5.32 2.62 3.01 5.63 1.04 0.39 5.60 0.67 0.86 225.42 BCR2 1.13 0.76 4.97 1.54 4.41 4.95 2.61 2.90 5.35 1.00 0.38 5.16 0.84 0.84 209.16 BCR2 1.58 0.53 5.22 1.64 4.06 5.30 2.72 3.08 5.74 1.07 0.40 5.50 0.72 0.88 239.95 BCR2 2.59 0.41 4.71 1.55 3.89 4.91 2.41 2.75 5.29 0.95 0.35 5.21 0.62 0.80 242.76 BCR2 2.38 0.39 4.52 1.51 3.79 4.80 2.25 2.63 5.23 0.91 0.32 5.25 0.60 0.77 249.57 BCR2 2.62 0.41 4.78 1.57 3.82 5.01 2.41 2.75 5.48 0.96 0.35 5.49 0.61 0.82 240.88 BCR2 3.12 0.48 4.65 1.50 3.85 4.80 2.37 2.70 5.17 0.94 0.35 5.05 0.62 0.79 223.20
G2 Av. 1.87±0.1 1.89±0.17 2.15±0.08 1.47±0.03 7.62±0.4 7.28±0.29 0.77±0.04 0.96±0.04 5.13±0.23 0.37±0.01 0.11±0.0 17.13±0.2 0.8±0.05 0.51±0.03 0.15±0.13 GSP2 Av. 1.17±0.09 1.97±0.53 5.90±0.22 2.29±0.08 14.81±0.76 27.13±0.94 1.80±0.08 2.59±0.09 16.23±0.58 1.00±0.04 0.25±0.01 57.53±2.89 0.89±0.04 1.51±0.05 1.89±0.68 BCR2 Av. 2.0±0.69 0.61±0.25 5.04±0.49 1.61±0.12 4.08±0.27 5.24±0.56 2.61±0.35 2.94±0.29 5.61±0.49 1.02±0.12 0.38±0.06 5.54±0.53 0.68±0.08 0.86±0.09 231.74±12.57
G2 (USGS) 2.5±0.4 1.34±0.16 2.4±0.3 1.4±0.12 7.9±0.7 7.2±0.7 0.8±0.2 0.92±N/A 4.3±N/A 0.4±N/A 0.11±N/A 18±N/A 0.5±N/A 0.48±N/A N/A GSP2 (USGS) 1.5±0.2 1.2±0.1 6.1±N/A 2.3±0.1 14±1.0 27±1.0 1.6±0.2 2.2±N/A 12±2.0 1.0±0.1 0.23±0.03 51±5.0 N/A N/A 2.1±0.6 BCR2 (USGS) 1.75±N/A 1.1±0.1 6.35±N/A 2.0±0.7 4.8±0.2 6.7±0.3 3.5±0.2 3.67±N/A 6.8±0.3 1.33±0.06 0.51±0.02 6.8±0.3 0.8±N/A 1.07±0.4 248±17
460 Ferrous Iron Determination
461 Table 4: Arabian Shield samples analysed for Ferric and Ferrous iron components using acid dissolution and titration. Whole rock powders were dissolved in a series of oxidising agents (ammonium metavanadate and ammonium ferrous sulphate) which are used to oxidise all Fe2+ to Fe3+ and V4+ to V5+ respectively. The derivation of ferrous iron (FeO) is calculated using a ‘blank’ solution of ammonium metavanadate (no FeO), the concentration of ammonium ferrous sulphate (0.00164459M) and the molar mass of FeO (71.8446). This procedure is described in detail in Appendix a5. An in house standard ‘TASBAS’ was frequently analysed to gauge data reliability (see below). Note the sum of FeO+Fe2O3 does differ slightly from Fe2O3T, which is the result of <100% recovery of all iron from powder dissolution.
Wt% Fe2O3T Sample Weight Sample Burette Sample Burette End Blank Burette Blank Burette Sample Map unit Sample Titre (ml) Blank Titre (ml) Wt% FeO Wt% Fe2O3 (XRF) (mg) Start (ml) (ml) Start (ml) End (ml) aa 166 4.19 61.35 25.20 46.30 21.10 0.20 25.20 25.00 0.72 3.39 aa 167 Abanat Suite 3.65 67.02 15.60 36.20 20.60 20.60 45.50 24.90 0.73 2.84 aa 168 4.05 69.96 0.50 20.60 20.10 20.60 45.50 24.90 0.78 3.19 abg 171 0.61 97.18 13.90 36.50 22.60 22.30 48.10 25.80 0.37 0.19 abg 172 Al Bad Granite Super 0.67 95.62 0.30 22.30 22.00 22.30 48.10 25.80 0.45 0.17 abg 173 Suite 0.70 95.47 0.20 21.20 21.00 22.70 46.00 23.30 0.27 0.40 abg 178 0.93 93.90 21.20 42.70 21.50 22.70 46.00 23.30 0.22 0.69 abg 179 0.98 93.51 18.60 40.50 21.90 0.20 25.30 25.10 0.39 0.55 abg 180 0.85 94.23 0.50 22.70 22.20 22.70 46.00 23.30 0.13 0.70 ad 194 3.24 71.47 3.40 18.60 15.20 0.20 25.30 25.10 1.57 1.49 ad 195 3.14 72.22 0.10 16.70 16.60 17.30 42.70 25.40 1.38 1.60 Admar Suite ad 196 3.54 71.74 16.70 31.90 15.20 17.30 42.70 25.40 1.61 1.75 ad 197 3.31 72.21 0.40 17.20 16.80 17.30 42.70 25.40 1.35 1.81 ao 83 1.13 91.42 0.10 17.40 17.30 19.10 44.00 24.90 0.94 0.08 ao 85 1.15 91.26 27.30 44.90 17.60 14.10 39.00 24.90 0.91 0.14 ao 87 9.27 28.79 0.20 8.30 8.10 0.70 25.60 24.90 6.62 1.91 Al Hafoor Suite ao 88 9.10 27.00 13.70 23.80 10.10 23.80 48.70 24.90 6.22 2.19 ao 98 1.71 85.43 0.70 16.60 15.90 0.70 25.20 24.50 1.14 0.44 ao 101 1.67 85.48 13.40 29.30 15.90 16.50 41.30 24.80 1.18 0.36 ay 186 5.75 45.71 1.10 9.50 8.40 4.10 28.90 24.80 4.07 1.23 ay 187 Al Ays Group 5.39 48.61 24.20 32.40 8.20 0.20 24.80 24.60 3.83 1.14 ay 206 11.13 25.25 4.60 15.20 10.60 0.10 24.70 24.60 6.29 4.14 CV 192 7.51 34.58 13.30 26.10 12.80 1.40 26.30 24.90 3.97 3.10 Mardabah Complex CV 193 7.51 34.94 0.50 13.20 12.70 13.20 38.50 25.30 4.09 2.96 dm 01a 9.46 27.61 0.10 13.60 13.50 0.20 25.20 25.00 4.72 4.21 dm 01b Makkah Suite 10.82 24.55 33.90 46.20 12.30 0.10 24.70 24.60 5.68 4.50 dm 01c 5.59 24.74 0.40 9.10 8.70 0.40 22.30 21.90 6.05 4.09 hla 109 2.45 46.53 9.60 24.00 14.40 4.10 28.90 24.80 2.54 2.77 hla 110 2.43 78.71 0.70 16.60 15.90 0.10 25.50 25.40 1.37 0.93 Haml Suite hla 111 2.13 78.22 9.00 24.20 15.20 0.20 24.80 24.60 1.36 0.92 hla 112 2.21 81.27 16.70 33.20 16.50 0.10 25.50 25.40 1.24 0.75
462 Table 4 (continued): Arabian Shield samples analysed for Ferric and Ferrous iron components using acid dissolution and titration. Whole rock powders were dissolved in a series of oxidising agents (ammonium metavanadate and ammonium ferrous sulphate) which are used to oxidise all Fe2+ to Fe3+ and V4+ to V5+ respectively. The derivation of ferrous iron (FeO) is calculated using a ‘blank’ solution of ammonium metavanadate (no FeO), the concentration of ammonium ferrous sulphate (0.00164459M) and the molar mass of FeO (71.8446). This procedure is described in detail in Appendix a5. An in house standard ‘TASBAS’ was frequently analysed to gauge data reliability (see below). Note the sum of FeO+Fe2O3 does differ slightly from Fe2O3T, which is the result of <100% recovery of all iron from powder dissolution.
Wt% Fe2O3T Sample Weight Sample Burette Start Sample Burette End Blank Burette Blank Burette Sample Map Unit Sample Titre (ml) Blank Titre (ml) Wt% FeO Wt% Fe2O3 (XRF) (mg) (ml) (ml) Start (ml) End (ml) hn 160 3.61 68.49 13.60 35.40 21.80 0.20 25.20 25.00 0.53 3.02 Hadn Formation hn 162 4.19 61.61 18.70 33.20 14.50 2.20 27.30 25.10 1.95 2.02 hwg 03 0.76 95.23 24.00 43.60 19.60 1.30 25.70 24.40 0.57 0.12 hwg 04 5.00 52.19 16.30 24.00 7.70 1.30 25.70 24.40 3.63 0.97 hwg 07 Al Hawiyah Suite 2.31 78.54 0.20 14.10 13.90 14.10 39.00 24.90 1.59 0.54 hwg 08 1.82 84.81 11.90 25.70 13.80 0.20 23.90 23.70 1.32 0.35 hwg 09 1.82 84.32 25.70 38.10 12.40 0.20 23.90 23.70 1.52 0.13 id 155 1.02 92.65 18.80 38.70 19.90 0.20 26.20 26.00 0.75 0.19 id 156 1.03 92.71 25.30 43.70 18.40 0.00 25.30 25.30 0.84 0.09 id 159 Idah Suite 1.24 90.18 12.40 29.50 17.10 0.80 25.30 24.50 0.93 0.21 id 163 0.86 93.8 0.30 21.60 21.30 0.20 26.20 26.00 0.57 0.23 id 164 0.96 94.05 21.60 43.40 21.80 0.20 26.20 26.00 0.51 0.40 ih 66 2.19 80.67 0.30 16.30 16.00 1.30 25.70 24.40 1.18 1.40 ih 68 1.90 83.65 25.50 42.20 16.70 2.10 26.80 24.70 1.08 0.69 ih 73 1.45 88.69 16.80 32.90 16.10 0.70 25.20 24.50 1.07 0.26 Ibn Hashbal Suite ih 74 1.52 87.14 0.40 16.50 16.10 16.50 41.30 24.80 1.13 0.26 ih 76 1.54 87.34 0.40 16.20 15.80 0.60 25.40 24.80 1.17 0.24 ih 79 1.43 884.2 17.40 34.60 17.20 19.10 44.00 24.90 0.10 1.32 kg 142 0.88 93.78 8.30 23.90 15.60 0.70 25.60 24.90 1.12 - kg 145 0.27 101.64 28.50 47.50 19.00 0.60 25.40 24.80 0.65 - kg 146 Malik Granite 0.22 101.4 23.90 44.10 20.20 0.70 25.60 24.90 0.53 - kg 148 0.71 90.7 0.10 19.10 19.00 19.10 44.00 24.90 0.74 - kg 150 1.07 93.31 0.80 25.30 24.50 2.20 26.80 24.60 0.01 1.06 ku 121 1.05 92.23 0.10 16.30 16.20 0.90 25.20 24.30 1.00 - ku 122 1.01 92.64 16.30 32.60 16.30 0.90 25.20 24.30 0.98 - Ar Ruwaydah Suite ku 123 1.20 92.31 32.60 47.80 15.20 0.90 25.20 24.30 1.12 - ku 139 0.78 95.05 0.40 20.50 20.10 20.50 45.30 24.80 0.56 0.16 kw 10 5.70 45.43 21.00 33.90 12.90 0.40 25.70 25.30 3.10 2.26 kw 11 6.75 38.63 2.70 15.30 12.60 0.40 25.70 25.30 3.73 2.61 kw 13 Kawr Suite 3.12 73.41 25.70 37.30 11.60 0.40 25.70 25.30 2.12 0.77 kw 14 4.84 54.44 0.30 8.10 7.80 0.10 24.70 24.60 3.50 0.95 kw 15 3.39 70.71 8.10 17.50 9.40 0.10 24.70 24.60 2.44 0.68
463 Table 4 (continued): Arabian Shield samples analysed for Ferric and Ferrous iron components using acid dissolution and titration. Whole rock powders were dissolved in a series of oxidising agents (ammonium metavanadate and ammonium ferrous sulphate) which are used to oxidise all Fe2+ to Fe3+ and V4+ to V5+ respectively. The derivation of ferrous iron (FeO) is calculated using a ‘blank’ solution of ammonium metavanadate (no FeO), the concentration of ammonium ferrous sulphate (0.00164459M) and the molar mass of FeO (71.8446). This procedure is described in detail in Appendix a5. An in house standard ‘TASBAS’ was frequently analysed to gauge data reliability (see below). Note the sum of FeO+Fe2O3 does differ slightly from Fe2O3T, which is the result of <100% recovery of all iron from powder dissolution.
Wt% Fe2O3T Sample Weight Sample Burette Sample Burette End Blank Burette Blank Burette Sample Map Unit Sample Titre (ml) Blank Titre (ml) Wt% FeO Wt% Fe2O3 (XRF) (mg) Start (ml) (ml) Start (ml) End (ml) kw 16 3.52 68.72 1.00 10.20 9.20 0.10 24.50 24.40 2.51 0.73 kw 18 5.14 50.62 0.10 14.00 13.90 14.00 39.10 25.10 2.51 2.35 kw 19 4.70 55.74 0.70 9.00 8.30 1.10 26.50 25.40 3.48 0.83 kw 21 3.34 70.45 9.00 20.40 11.40 1.10 26.50 25.40 2.25 0.84 kw 22 3.50 68.26 29.60 41.20 11.60 0.90 26.00 25.10 2.24 1.01 kw 23 3.40 69.24 1.70 12.90 11.20 0.70 24.70 24.00 2.10 1.07 kw 24 3.23 71.37 13.50 26.30 12.80 0.30 25.60 25.30 1.99 1.02 kw 29 1.84 84.29 28.90 46.70 17.80 0.10 24.50 24.40 0.89 0.85 kw 30b 7.74 85.64 13.20 29.80 16.60 1.20 25.80 24.60 1.06 0.51 kw 30p 1.69 33.85 29.80 39.10 9.30 1.20 25.80 24.60 5.13 2.04 kw 31 1.68 85.33 10.20 28.90 18.70 0.10 24.50 24.40 0.76 0.84 kw 32 8.85 29.59 1.40 11.20 9.80 1.70 26.40 24.70 5.71 2.50 kw 33 7.92 33.31 12.70 21.00 8.30 0.70 25.80 25.10 5.72 1.56 kw 35 3.85 65.60 25.80 37.60 11.80 0.70 25.80 25.10 2.30 1.29 kw 36 Kawr Suite 2.04 82.67 0.30 17.20 16.90 12.90 37.40 24.50 1.04 0.88 kw 38 2.33 79.14 12.90 27.60 14.70 0.70 24.70 24.00 1.33 0.85 kw 40 0.89 93.50 11.40 29.60 18.20 0.90 26.00 25.10 0.84 - kw 41 1.10 91.35 27.60 43.50 15.90 0.70 24.70 24.00 1.01 - kw 42 5.56 45.20 25.30 33.40 8.10 0.20 25.30 25.10 4.27 0.82 kw 43 8.22 31.52 12.70 20.70 8.00 2.70 27.30 24.60 5.97 1.58 kw 44 1.40 88.35 26.30 42.90 16.60 0.30 25.60 25.30 1.12 0.16 kw 45 1.46 88.19 20.40 36.20 15.80 1.10 26.50 25.40 1.23 0.09 kw 46 1.71 85.31 17.20 35.70 18.50 12.90 37.40 24.50 0.80 0.82 kw 50 1.57 86.56 26.60 41.50 14.90 1.70 26.40 24.70 1.28 0.14 kw 51b 1.59 86.47 11.20 26.60 15.40 1.70 26.40 24.70 1.22 0.16 kw 51p 0.87 93.64 0.50 19.70 19.20 22.60 48.00 25.40 0.75 0.04 kw 52b 1.52 92.86 11.40 28.70 17.30 0.40 25.00 24.60 0.89 - kw 52p 0.96 88.04 28.70 46.80 18.10 0.40 25.00 24.60 0.84 0.59 kw 55 8.22 32.59 0.20 11.40 11.20 0.90 26.00 25.10 4.84 2.84 ky 124 Al Khushaymiyah 0.76 95.52 2.60 11.70 9.10 14.00 39.10 25.10 1.90 - ky 125 Suite 0.74 95.57 1.60 18.50 16.90 18.50 42.30 23.80 0.82 -
464 Table 4 (continued): Arabian Shield samples analysed for Ferric and Ferrous iron components using acid dissolution and titration. Whole rock powders were dissolved in a series of oxidising agents (ammonium metavanadate and ammonium ferrous sulphate) which are used to oxidise all Fe2+ to Fe3+ and V4+ to V5+ respectively. The derivation of ferrous iron (FeO) is calculated using a ‘blank’ solution of ammonium metavanadate (no FeO), the concentration of ammonium ferrous sulphate (0.00164459M) and the molar mass of FeO (71.8446). This procedure is described in detail in Appendix a5. An in house standard ‘TASBAS’ was frequently analysed to gauge data reliability (see below). Note the sum of FeO+Fe2O3 does differ slightly from Fe2O3T, which is the result of <100% recovery of all iron from powder dissolution.
Wt% Fe2O3T Sample Weight Sample Burette Sample Burette Blank Burette Blank Burette Sample Map Unit Sample Titre (ml) Blank Titre (ml) Wt% FeO Wt% Fe2O3 (XRF) (mg) Start (ml) End (ml) Start (ml) End (ml) ky 126 0.78 94.90 2.80 22.70 19.90 18.50 42.30 23.80 0.47 0.26 ky 129 Al Khushaymiyah Suite 2.73 75.50 1.70 17.30 15.60 20.50 45.30 24.80 1.38 1.19 ky 130 2.84 74.36 11.70 31.60 19.90 14.00 39.10 25.10 0.79 1.96 MCR 104 10.53 25.46 13.70 26.60 12.90 0.40 25.70 25.30 5.52 4.39 Bani Ghayy Group MCR 105 9.39 27.66 25.60 42.50 16.90 23.80 48.70 24.90 3.28 5.74 MD 93 1.60 86.48 17.50 28.80 11.30 0.70 25.90 25.20 1.82 - Al Hafoor Suite MD 95 1.59 87.53 0.50 17.80 17.30 1.40 26.30 24.90 0.98 0.50 mr 188 4.40 59.57 28.80 42.70 13.90 0.20 25.40 25.20 2.15 2.01 mr 189 4.24 60.48 1.10 13.60 12.50 0.20 25.40 25.20 2.38 1.59 Mardabah Complex mr 190 4.48 58.21 13.60 26.80 13.20 0.20 25.40 25.20 2.34 1.88 mr 191 4.53 57.51 12.50 25.50 13.00 2.10 26.80 24.70 2.31 1.97 mu 131 8.49 31.32 0.20 17.50 17.30 0.70 25.90 25.20 2.86 5.31 mu 132 8.07 33.59 0.60 13.70 13.10 23.80 48.70 24.90 3.98 3.64 Murdama Group mv 134 3.31 70.05 14.80 30.00 15.20 0.60 24.70 24.10 1.44 1.71 mv 135 3.06 73.37 30.00 44.70 14.70 0.60 24.70 24.10 1.45 1.45 nr 117 1.56 87.67 0.30 14.80 14.50 0.60 24.70 24.10 1.24 0.18 nr 119 1.46 87.72 12.40 27.10 14.70 0.80 25.10 24.30 1.24 0.08 Najirah Granite nr 120 1.48 87.35 0.30 15.40 15.10 2.20 26.80 24.60 1.23 0.11 nr 136 2.15 80.80 27.10 46.20 19.10 0.80 25.10 24.30 0.73 1.34 rt 181 8.38 31.66 28.20 37.30 9.10 3.00 28.20 25.20 5.77 1.97 rt 182 8.36 31.53 0.40 8.40 8.00 3.00 28.20 25.20 6.19 1.48 Rithmah Complex rt 183 8.16 32.56 8.40 16.50 8.10 3.00 28.20 25.20 5.96 1.54 rt 185 9.15 28.21 29.50 38.40 8.90 0.80 25.30 24.50 6.27 2.18 js 200 2.17 80.16 25.10 40.60 15.50 0.40 24.90 24.50 1.27 0.75 js 201 2.32 79.68 24.90 39.20 14.30 0.40 24.90 24.50 1.45 0.71 Jar-Salajah Complex js 202 2.26 80.48 17.30 32.50 15.20 20.50 45.30 24.80 1.35 0.76 js 203 1.82 84.75 1.50 17.80 16.30 0.40 24.90 24.50 1.10 0.60 sf 208 1.02 92.33 1.90 20.40 18.50 1.30 26.00 24.70 0.76 0.17 sf 209 1.41 88.14 26.80 48.60 21.80 2.20 26.80 24.60 0.36 1.01 Subh Suite sf 211 1.41 88.99 20.40 38.90 18.50 1.30 26.00 24.70 0.79 0.53 sf 213 7.44 35.12 1.60 12.70 11.10 0.60 25.20 24.60 4.36 2.59
465 Table 4 (continued): Arabian Shield samples analysed for Ferric and Ferrous iron components using acid dissolution and titration. Whole rock powders were dissolved in a series of oxidising agents (ammonium metavanadate and ammonium ferrous sulphate) which are used to oxidise all Fe2+ to Fe3+ and V4+ to V5+ respectively. The derivation of ferrous iron (FeO) is calculated using a ‘blank’ solution of ammonium metavanadate (no FeO), the concentration of ammonium ferrous sulphate (0.00164459M) and the molar mass of FeO (71.8446). This procedure is described in detail in Appendix a5. An in house standard ‘TASBAS’ was frequently analysed to gauge data reliability (see below). Note the sum of FeO+Fe2O3 does differ slightly from Fe2O3T, which is the result of <100% recovery of all iron from powder dissolution.
Wt% Fe2O3T Sample Weight Sample Burette Sample Burette Sample Titre Blank Burette Blank Burette Sample Map Unit Blank Titre (ml) Wt% FeO Wt% Fe2O3 (XRF) (mg) Start (ml) End (ml) (ml) Start (ml) End (ml) si 114 1.93 83.7 0.60 18.70 18.10 2.20 27.30 25.10 0.95 0.88 Siham Group si 116 1.26 90.29 12.00 29.90 17.90 1.00 25.60 24.60 0.84 0.32 su 214 Shufayyah 4.59 56.59 12.70 24.30 11.60 0.60 25.20 24.60 2.61 1.69 su 215 4.41 58.39 24.30 35.70 11.40 0.60 25.20 24.60 2.56 1.56 su 216 Complex 4.47 57.7 0.20 12.00 11.80 1.00 25.60 24.60 2.52 1.67 tfv 02 At Ta'if Group 11.49 23.33 24.80 33.90 9.10 0.20 24.80 24.60 7.54 3.12 VG 198 Admar Suite 0.73 95.37 0.60 18.80 18.20 13.20 38.50 25.30 0.84 - wb 61 3.75 65.45 25.70 37.10 11.40 4.10 28.90 24.80 2.32 1.17 wb 62 3.85 65.24 3.60 14.00 10.40 7.20 31.60 24.40 2.43 1.15 Wadbah Suite wb 63 3.48 68.15 14.00 24.90 10.90 7.20 31.60 24.40 2.25 0.98 wb 65 3.07 73.57 20.70 32.90 12.20 2.70 27.30 24.60 1.91 0.95 154(d) Abanat Suite 1.43 88.52 1.50 19.60 18.10 0.00 25.30 25.30 0.92 0.40
466 Table 4 (continued): In house standards analysed for Ferric and Ferrous iron components using acid dissolution and titration. These are individual whole rock powders routinely analysed in conjunction with the above unknown Saudi Arabian samples to gauge data reliability. The ferrous iron content is calculated in exactly the same manner as described above. The reproducibility of these standards provides confidence in the technique, but also the reliability of the unknown Saudi Arabian samples. This procedure is described in detail in Appendix a5. Note* the sum of FeO+Fe2O3 does differ slightly from Fe2O3T, which is the result of <100% recovery of all iron from powder dissolution.
Sample Weight Sample Burette Sample Burette End Blank Burette Blank Burette End Sample Wt% Fe2O3T (XRF) Sample Titre (ml) Blank Titre (ml) Wt% FeO Wt% Fe2O3 (mg) Start (ml) (ml) Start (ml) (ml) TASBAS#1 [standard] 12.71 15.15 24.70 33.90 9.20 0.10 24.70 24.60 11.53 - TASBAS#2 [standard] 12.71 15.51 25.20 37.30 12.10 7.20 31.60 24.40 9.00 2.71 TASBAS#3 [standard] 12.71 15.59 0.20 12.40 12.20 0.80 25.30 24.50 8.95 2.77 TASBAS#4 [standard] 12.71 15.67 15.40 27.30 11.90 14.10 39.00 24.90 9.41 2.25 TASBAS#5 [standard] 12.71 15.35 0.90 13.30 12.40 1.40 26.30 24.90 9.24 2.45 TASBAS#6 [standard] 12.71 16.29 0.60 12.50 11.90 2.10 26.80 24.70 8.91 2.81 TASBAS#7 [standard] 12.71 15.00 32.40 45.30 12.90 1.00 25.60 24.60 8.85 2.88 TASBAS#8 [standard] 12.71 15.25 0.30 12.70 12.40 2.70 27.30 24.60 9.07 2.63 TASBAS#9 [standard] 12.71 14.61 19.70 32.70 13.00 1.00 25.60 24.60 9.01 2.70 TASBAS#10 [standard] 12.71 15.11 27.60 40.70 13.10 0.40 25.70 25.30 9.16 2.53 TASBAS#11 [standard] 12.71 15.76 28.90 40.90 12.00 2.20 27.30 25.10 9.43 2.23 TASBAS#12 [standard] 12.71 15.31 16.50 28.80 12.30 0.00 25.30 25.30 9.63 2.01 TASBAS#13 [standard] 12.71 15.78 2.90 15.60 12.70 20.60 45.50 24.90 8.77 2.96 TASBAS#14 [standard] 12.71 15.69 25.50 38.40 12.90 13.20 38.50 25.30 8.96 2.75 TASBAS#15 [standard] 12.71 15.17 0.60 13.90 13.30 22.30 48.10 25.80 9.35 2.32 TASBAS#16 [standard] 12.71 15.42 0.50 11.90 11.40 0.20 23.90 23.70 9.05 2.66 TASBAS#17 [standard] 12.71 15.31 1.40 13.40 12.00 16.50 41.30 24.80 9.48 2.17 TASBAS#18 [standard] 12.71 16.03 25.60 37.30 11.70 0.70 25.20 24.50 9.06 2.64 TASBAS#19 [standard] 12.71 15.12 16.20 28.50 12.30 0.60 25.40 24.80 9.38 2.29 TASBAS#20 [standard] 12.71 15.86 0.50 12.40 11.90 0.80 25.10 24.30 8.87 2.85 TASBAS#21 [standard] 12.71 14.81 17.80 30.10 12.30 1.30 26.00 24.70 9.50 2.16 TASBAS#22 [standard] 12.71 15.82 25.90 38.00 12.10 0.70 25.90 25.20 9.39 2.27 TASBAS#23 [standard] 12.71 15.65 22.70 33.70 11.00 18.50 42.30 23.80 9.28 2.40 TASBAS#24 [standard] 12.71 15.33 0.20 11.40 11.20 0.40 25.00 24.60 9.91 1.69 TASBAS#25 [standard] 12.71 14.97 0.50 12.90 12.40 12.90 37.40 24.50 9.17 2.52 TASBAS#26 [standard] 12.71 15.45 24.70 36.40 11.70 0.10 24.70 24.60 9.47 2.19 TASBAS#27 [standard] 12.71 15.27 1.70 13.20 11.50 1.20 25.80 24.60 9.73 1.90 TASBAS#28 [standard] 12.71 15.74 0.90 12.70 11.80 0.70 25.80 25.10 9.58 2.06 TASBAS#29 [standard] 12.71 15.91 0.90 13.50 12.60 0.30 25.60 25.30 9.05 2.65 TASBAS#30 [standard] 12.71 15.72 22.30 34.90 12.60 0.40 22.30 21.90 6.71 5.25 TASBAS AV. 12.71 15.46 12.09 24.61 9.34 2.33
467 Appendix 6: Whole Rock Sm-Nd and Sr Isotope Data
468 Table1: Nd isotopes of sampled granitic units from the Arabian Shield analysed by TIMS (Finnigan MAT262). Sample weights are calculated based on a nominal 2µg of Nd and corresponding Nd XRF concentration (Appendix 5). Isotope dilution is measured with a nominal 0.4g of 150Nd/147Sm enriched spike (samples with elevated Nd values have the spike weight ratio adjusted). 150Nd/144Nd is measured to calculate the Nd concentration (µgg-1) in the sample, hence the amount of spike. This is then applied as a correction on the measured 143Nd/144Nd and produces the unmixed 143Nd/144Nd (Table 1 continued). A more detailed explanation of this procedure is seen in Appendix a6. Analysed samples were run in conjunction with internal standards (JNdi1, Tanaka et al., 2000) and international standards (G2, USGS) to determine machine accuracy and reliability of results respectively.
Sample Weight Sm-Nd Spike Outliers in 2σ test Outliers in 2σ test (50 Sample+Map Unit 143Nd/144Nd 2σ 2σ [%] 150Nd/144Nd 2σ 2σ [%] Nd (µgg-1) (g) Weight (g) (100 values) values) Abanat Suite [aa166] 0.04904 1.20773 0.512512 8.3 0.0016 2 0.443651 28.7 0.0065 2 138.61 Admar Suite [ad194] 0.06541 0.41803 0.512467 11.1 0.0022 7 0.412202 32.2 0.0078 2 42.42 Al Bad Suite [abg179] 0.08197 0.40295 0.512688 8.1 0.0016 5 0.459139 29.8 0.0065 2 25.74 Al Hafoor Suite [ao85] 0.13398 0.42601 0.512457 13.3 0.0026 7 0.464887 33.4 0.0072 2 16.23 Al Hawiyah Suite [hwg07] 0.04900 0.45746 0.512570 8.3 0.0016 3 0.464897 57.1 0.0123 2 47.65 Al Khuashaymiyah Suite [ky129] 0.20200 0.41565 0.512375 7.7 0.0015 6 0.395179 25.9 0.0065 1 15.12 Ar Ruwaydah Suite [ku139] 0.16899 0.41076 0.512491 7.5 0.0015 4 0.438202 36.1 0.0082 4 14.05 Haml Suite [hla110] 0.10036 0.41703 0.512527 7.1 0.0014 6 0.461619 45.4 0.0098 2 21.52 Ibn Hashbal Suite [ih68] 0.05418 1.21097 0.512463 9.3 0.0018 1 0.441822 29.3 0.0066 1 126.92 Idah Suite [id159] 0.09097 0.41195 0.512559 8.0 0.0016 3 0.449785 38.3 0.0085 3 24.75 Jar-Salajrah Complex [js202] 0.13339 0.41770 0.512631 7.5 0.0015 4 0.460054 39.7 0.0086 1 16.33 Kawr Suite [kw42] 0.05293 1.03360 0.512678 8.0 0.0016 8 0.463567 25.9 0.0056 2 100.25 Kawr Suite [kw51p] 0.12798 0.42605 0.512577 6.7 0.0013 6 0.442612 31.6 0.0071 3 18.83 Makkah Suite [dm01a] 0.08003 0.41712 0.512646 11.2 0.0022 3 0.482656 71.4 0.0148 1 24.68 Malik Granite [kg150] 0.09134 0.40913 0.512535 9.8 0.0019 2 0.416533 25.4 0.0061 2 29.01 Mardabah Complex [mr191] 0.06045 0.40340 0.512571 9.2 0.0018 3 0.427952 46.3 0.0108 3 40.64 Najirah Granite [nr120] 0.05575 0.46119 0.512665 9.0 0.0018 3 0.392761 41.9 0.0107 3 61.75 Rithmah Complex [rt185] 0.14518 0.41919 0.512886 7.9 0.0015 4 0.673919 40.7 0.0060 3 7.68 Shufayyah Complex [su216] 0.12580 0.42171 0.512703 7.6 0.0015 4 0.465696 39.8 0.0085 2 17.05 Subh Suite [sf209] 0.07435 0.41616 0.512715 9.5 0.0019 2 0.463132 35.3 0.0076 3 28.79 Wadbah Suite [wb65] 0.05875 0.84753 0.512524 8.1 0.0016 5 0.442634 37.7 0.0085 1 81.59 G2#9 [USGS Standard] 0.05475 0.61277 0.512262 8.6 0.0017 6 0.485373 24.7 0.0051 3 52.41 G2#10 [USGS Standard] 0.05060 0.61275 0.512253 8.7 0.0017 4 0.504008 35.4 0.007 2 52.75 - 51.2±3.9 G2 Sm/Nd Spike F (n=11). UofA Av. 0.05451 0.68699 0.512266 8.7 - - 0.526271 32.4 - G2 [USGS] 55±6 Blank#1562 [Procedural] - 0.05138 - - - - - 3.6 - - 92 (pg) Blank#1563 [Procedural] - 0.05436 - - - - - 4 - - 87(pg) JNdi1#145 [Standard] - - 0.512079 8.4 0.0016 5 JNdi1#145 [Standard] - - 0.512079 9.6 0.0019 5 - - - - - JNdi1#145 [Standard] - - 0.512081 9.6 0.0019 4 - - - - - JNdi1#145 [Standard] - - 0.512076 7.2 0.0014 7 - - - - - JNdi1#146 [Standard] - - 0.512079 32.4 0.0063 16 *Note University of Adelaide Finnigan MAT262 JNdi1 average =0.512085±9.5 (n=650). JNdi1 Tanaka et al. (2000) - - 0.512115 7 - - See methods for explaination
469 Table1 (continued): Sm isotopes of sampled granitic units from the Arabian Shield analysed by TIMS (Finnigan MAT262). Similarly as above (Table 1), 147Sm/149Sm is measured to calculate the concentration of Sm (µgg-1) in the sample, hence the amount of 147Sm in the spike. 152Sm/149Sm is measured to correct for fractionation caused by the mass spectrometer. 147Sm/144Nd is calculated from the measured concentrations of Sm and Nd in the sample. A more detailed explanation of this procedure is seen in Appendix a6. Analysed samples were run in conjunction with international standards (G2, USGS) to determine machine accuracy and reliability of results respectively.
Outliers in 2σ test Outliers in 2σ test Unmixed Sample+Map Unit 147Sm/149Sm 1σ 1σ [%] 152Sm/149Sm 1σ 1σ [%] Sm(µgg-1) 147Sm/144Nd (20 values) (20 values) 143Nd/144Nd Abanat Suite [aa166] 5.673169 0.0004548 0.0080 1 1.885007 0.0002181 0.0116 0 21.11 0.512466 0.0147 Admar Suite [ad194] 5.181494 0.0006742 0.0130 0 1.898857 0.0007821 0.0412 0 6.12 0.512428 0.0506 Al Bad Suite [abg179] 4.545009 0.0008655 0.0190 0 1.898976 0.0003520 0.0185 0 5.60 0.512639 0.0553 Al Hafoor Suite [ao85] 5.756123 0.0013031 0.0226 1 1.897434 0.0006457 0.0340 1 2.66 0.512406 0.1166 Al Hawiyah Suite [hwg07] 5.467048 0.0008018 0.0147 1 1.895073 0.0002871 0.0151 0 8.35 0.512520 0.0371 Al Khuashaymiyah Suite [ky129] 4.424315 0.0013400 0.0303 0 1.896999 0.0005438 0.0287 3 2.44 0.512340 0.1272 Ar Ruwaydah Suite [ku139] 4.667148 0.0012864 0.0276 0 1.896432 0.0004794 0.0253 0 2.68 0.512446 0.1158 Haml Suite [hla110] 5.308848 0.0007713 0.0145 0 1.895383 0.0001809 0.0095 0 3.86 0.512478 0.0803 Ibn Hashbal Suite [ih68] 6.356705 0.0011176 0.0176 1 1.880912 0.0002896 0.0154 1 16.61 0.512417 0.0187 Idah Suite [id159] 4.854929 0.0015741 0.0324 1 1.892925 0.0020020 0.1058 0 4.74 0.512512 0.0654 Jar-Salajrah Complex [js202] 4.948575 0.0005603 0.0113 1 1.889652 0.0008525 0.0451 0 3.20 0.512582 0.0969 Kawr Suite [kw42] 4.511326 0.0005760 0.0128 1 1.900780 0.0009821 0.0517 0 22.47 0.512628 0.0138 Kawr Suite [kw51p] 4.964150 0.0020876 0.0421 0 1.898209 0.0005849 0.0308 1 3.37 0.512532 0.0919 Makkah Suite [dm01a] 4.857291 0.0018513 0.0381 0 1.894055 0.0011075 0.0585 0 5.45 0.512592 0.0569 Malik Granite [kg150] 3.934045 0.0006273 0.0159 1 1.898430 0.0003763 0.0198 1 6.24 0.512495 0.0497 Mardabah Complex [mr191] 4.568744 0.0006542 0.0143 4 1.893287 0.0002805 0.0148 5 7.58 0.512529 0.0409 Najirah Granite [nr120] 3.220440 0.0004118 0.0128 0 1.911109 0.0003646 0.0191 1 15.38 0.512630 0.0202 Rithmah Complex [rt185] 6.586285 0.0021786 0.0331 0 1.882154 0.0007136 0.0379 1 2.05 0.512790 0.1513 Shufayyah Complex [su216] 4.566352 0.0002388 0.0052 2 1.890679 0.0003333 0.0176 1 3.81 0.512653 0.0813 Subh Suite [sf209] 4.527382 0.0017313 0.0382 0 1.894462 0.0008379 0.0442 0 6.43 0.512665 0.0482 Wadbah Suite [wb65] 5.496425 0.0025590 0.0466 1 1.890941 0.0006602 0.0349 0 12.84 0.512479 0.0241 G2#9 [USGS Standard] 7.376797 0.0015740 0.0213 1 1.881962 0.0003704 0.0197 0 6.90 0.512206 0.0797 G2#10 [USGS Standard] 7.850400 0.0013838 0.0176 2 1.876037 0.0006784 0.0362 0 6.94 0.512194 0.0795 - 6.7±0.5 0.512201±20 0.0796 G2 Sm/Nd Spike F (n=11). UofA Av. 8.349698 - 0.0237 - 1.883186 - 0.0425 G2 [USGS] 7.2±0.7 Blank#1562 [Procedural] 43.015123 9.57473463 22.26 1 - - - - 20.14 pg - 0.1317 Blank#1563 [Procedural] 40.080727 2.79540365 6.974 0 - - - - 23.37 pg - 0.1620
470 Table1 (continued): Sr isotopes of sampled granitic units from the Arabian Shield analysed by TIMS (Finnigan MAT262). The amount of Sr in the powdered sample is determined using the Sr XRF concentrations (Appendix 5) and the sample weight (see above). Samples with ~<2g were analysed using a Rhenium filament. A more detailed explanation of this procedure is seen in Appendix a6. Analysed samples were run in conjunction with internal standards (SRM987, University of Adelaide) and international standards (G2, USGS) to determine machine accuracy and reliability of results respectively.
Outliers in 2σ test (100 Sample+Map Unit Sample Weight (g) Amount of Sr 87Sr/86Sr 1σ 1σ [%] 2σ 2σ [%] Sr (ppm) Rb (ppm) values) Abanat Suite [aa166] 0.04904 0.48550 0.990950 69.4 0.007 14.2 0.0014 4 9.9 148 Admar Suite [ad194] 0.06541 58.49616 0.703946 58.7 0.0083 12 0.0017 5 894.3 41 Al Bad Suite [abg179] 0.08197 0.76232 1.089832 73.8 0.0068 15.1 0.0014 4 9.3 159 Al Hafoor Suite [ao85] 0.13398 5.88172 0.806404 63.2 0.0078 12.8 0.0016 2 43.9 179 Al Hawiyah Suite [hwg07] 0.04900 8.86410 0.729219 52.8 0.0072 10.8 0.0015 5 180.9 200 Al Khuashaymiyah Suite [ky129] 0.20200 135.90560 0.707630 50.9 0.0072 10.5 0.0015 5 672.8 107 Ar Ruwaydah Suite [ku139] 0.16899 50.00414 0.710556 56.4 0.0079 11.6 0.0016 5 295.9 88 Haml Suite [hla110] 0.10036 24.88928 0.715626 58.9 0.0082 12 0.0017 2 248.0 125 Idah Suite [id159] 0.09097 2.99291 0.803196 61.6 0.0077 12.4 0.0015 2 32.9 61 Ibn Hashbal Suite [ih68] 0.05418 2.37850 0.735379 57.7 0.0078 11.8 0.0016 4 43.9 136 Jar-Salajrah Complex [js202] 0.13339 27.71844 0.706122 57.1 0.0081 11.6 0.0016 4 207.8 26 Kawr Suite [kw42] 0.05293 5.14480 0.727509 64.2 0.0088 13.2 0.0018 5 97.2 97 Kawr Suite [kw51p] 0.12798 7.06450 0.760414 62.3 0.0082 127 0.0017 4 55.2 110 Makkah Suite [dm01a] 0.08003 66.12879 0.704364 49.8 0.0071 10.2 0.0015 5 826.3 40 Malik Granite [kg150] 0.09134 9.32581 0.742676 62.2 0.0084 12.6 0.0017 3 102.1 165 Mardabah Complex [mr191] 0.06045 34.49277 0.704534 46.4 0.0066 9.5 0.0014 5 570.6 41 Najirah Granite [nr120] 0.05575 3.21678 0.779715 95.6 0.0123 19.4 0.0025 3 57.7 182 Rithmah Complex [rt185] 0.14518 48.99825 0.704028 50.6 0.0072 10.3 0.0015 4 337.5 16 Shufayyah Complex [su216] 0.12580 44.13064 0.706177 50.5 0.0072 10.4 0.0015 5 350.8 43 Subh Suite [sf209] 0.07435 2.45355 0.752144 54.2 0.0072 11.1 0.0015 4 33.0 67 Wadbah Suite [wb65] 0.05875 1.28663 0.762602 52.4 0.0069 10.7 0.0014 4 21.9 63 G2#9 [USGS Standard] 0.05475 26.17050 0.709729 62.3 0.0088 12.7 0.0018 4 478 - G2#10 [USGS Standard] 0.05060 24.18680 0.709743 58.1 0.0082 11.7 0.0016 1 478 - 0.709741 G2 Sr (n=11). UofA Av. - 58.0 0.0082 11.8 0.0017 - - - [G2 USGS] 0.709770±7 Blank#1562 [Procedural] - Spike F 0.12293 g 0.84 - - - - - 719 pg - Blank#1563 [Procedural] - Spike F 0.12771 g 0.63 - - - - - 1034 pg - SRM987#398 [Standard] - - 0.710225 51.6 0.0073 10.6 0.0015 5 SRM987#398 [Standard] *Note Finnigan Recommended 87Sr/86Sr 0.710224 67.0 0.0094 13.7 0.0019 4 - - SRM987#398 [Standard] 0.710234 58.3 0.0082 11.8 0.0017 3 - - SRM987#398 [Standard] =0.710220-0.710260 0.710235 60.0 0.0085 12.2 0.0017 3 - - SRM987#398 [Standard] - - 0.710233 63.1 0.0089 12.8 0.0018 3 - SRM987#398 [Standard] - - 0.710232 59.5 0.0084 12.0 0.0017 2 - SRM987 [Standard] n=744 Adelaide University MAT262 0.710268 84.0 0.0118 17.2 0.0024 - -
471 Table 2: Calculated model ages for Arabian Shield granitic suites analysed by TIMS (Finnigan MAT262). Values were processed using a Sm-Nd isotopic spreadsheet (University of Adelaide) with 143Nd/144Nd CHUR (t=0): 0.512638; 147Sm/144Nd (t=0): 0.1966; 143Nd/144Nd DM (t=0): 0.513150 and 147Sm/144Nd DM (t=0): 0.2145 ratios taken from Goldstein et al. (1984). Model ages are calculated based on these ratio values. A more detailed explanation of this procedure is seen in Appendix a6. The age of the granitic suites is the weighted average age directly dated in Chapter 3.2. However, the Abanat Suite and Rithmah Complex are not directly dated, so values obtained from Johnson (2006) are used. Calculated error values are 2σ.
Unmixed Age of Depleted Sample+Map Unit Nd µgg-1 147Sm/144Nd Sm µgg-1 Present Day ɛNd Age Ma (t) 143Nd/144Nd (t) ɛNd (t) CHUR (t) 87Sr/86Sr (t) 143Nd/144Nd Mantle (t) 585 0.512113 4.47±0.13 851±7 251±9 0.619404 Abanat Suite [aa166] 0.512466 138.61 0.0921 21.11 -3.35 570 0.512122 4.27±0.13 851±7 251±9 - Admar Suite [ad194] 0.512428 42.42 0.0873 6.12 -4.09 599.2±3.8 0.512086±6 4.29±0.12 865±7 293±8 0.702819 Al Bad Suite [abg179] 0.512639 25.74 0.1317 5.60 0.02 597.4±4.8 0.512124±7 4.99±0.14 940±10 (-)2±14 0.652145 Al Hafoor Suite [ao85] 0.512406 16.23 0.0991 2.66 -4.51 636±4 0.511994±7 3.42±0.13 982±7 362±9 0.698286 Al Hawiyah Suite [hwg07] 0.512520 47.65 0.1060 8.35 -2.31 591.9±5.2 0.512109±7 4.55±0.14 886±8 200±10 0.702226 Al Khuashaymiyah Suite [ky129] 0.512340 15.12 0.0974 2.44 -5.81 601.2±5.2 0.511956±7 1.81±0.13 1054±7 459±9 0.703679 Ar Ruwaydah Suite [ku139] 0.512446 14.05 0.1153 2.68 -3.74 612.1±4.9 0.511984±7 2.64±0.14 1079±9 359±11 0.702783 Haml Suite [hla110] 0.512478 21.52 0.1086 3.86 -3.13 608.6±8.1 0.512045±8 3.73±0.16 967±8 279±10 0.702543 Ibn Hashbal Suite [ih68] 0.512417 126.92 0.0791 16.61 -4.30 617.6±5.2 0.512098±7 4.99±0.13 825±6 286±8 0.753914 Idah Suite [id159] 0.512512 24.75 0.1158 4.74 -2.46 607.9±6.6 0.512051±8 3.83±0.15 985±9 238±11 0.654438 Jar-Salajrah Complex [js202] 0.512582 16.33 0.1186 3.20 -1.10 693.2±6.3 0.512043±8 5.84±0.15 902±9 110±12 0.702826 Kawr Suite [kw42] 0.512628 100.25 0.1356 22.47 -0.39 611.7±6.5 0.512075±8 4.39±0.16 1027±11 50±15 0.701513 Kawr Suite [kw51p] 0.512532 18.83 0.1084 3.37 -2.08 608±12 0.512100±7 4.79±0.14 888±8 184±10 0.707887 Makkah Suite [dm01a] 0.512592 24.68 0.1336 5.45 -0.90 845.6±4.9 0.511852±7 5.94±0.14 1050±10 112±15 0.703102 Malik Granite [kg150] 0.512495 29.01 0.1301 6.24 -2.78 599.6±5 0.511985±7 2.33±0.14 1180±10 327±14 0.700113 Mardabah Complex [mr191] 0.512529 40.64 0.1128 7.58 -2.13 525.6±4.7 0.512141±7 3.51±0.14 930±8 199±11 0.702662 Najirah Granite [nr120] 0.512630 61.75 0.1506 15.38 -0.14 607±7.9 0.512032±10 3.44±0.19 1236±13 24±20 0.696248 Rithmah Complex [rt185] 0.512790 7.68 0.1615 2.05 2.97 600.0 0.512157 5.67±0.16 1033±15 (-)662±26 0.702784 Shufayyah Complex [su216] 0.512653 17.05 0.1353 3.81 0.29 715.4±3.6 0.512019±7 5.91±0.13 956±11 (-)36±15 0.703013 Subh Suite [sf209] 0.512665 28.79 0.1351 6.43 0.53 698.7±5.5 0.512047±8 6.04±0.15 930±10 (-)68±15 0.699021 Wadbah Suite [wb65] 0.512479 81.59 0.0952 12.84 -3.11 615.9±4.9 0.512094±7 4.88±0.13 858±7 240±9 0.687647
472 Table3: Nd isotopes of sampled country rocks and mafic autolith units from the Arabian Shield analysed by TIMS (Finnigan MAT262). Sample weights are calculated based on a nominal 2µg of Nd and corresponding Nd XRF concentration (Appendix 5). Isotope dilution is measured with a nominal 0.4g of 150Nd/147Sm enriched spike (samples with elevated Nd values have the spike weight ratio adjusted). 150Nd/144Nd is measured to calculate the Nd concentration (µgg-1) in the sample, hence the amount of spike. This is then applied as a correction on the measured 143Nd/144Nd and produces the unmixed 143Nd/144Nd (Table 3 continued). A more detailed explanation of this procedure is seen in Appendix a6. Analysed samples were run in conjunction with internal standards (JNdi1, Tanaka et al., 2000) and international standards (G2, USGS) to determine machine accuracy and reliability of results respectively.
Sample Sm-Nd Spike Outliers in 2σ test Outliers in 2σ test Sample+Map Unit 143Nd/144Nd 2σ 2σ [%] 150Nd/144Nd 2σ 2σ [%] Nd (µgg-1) Weight (g) Weight (g) (100 values) (50 values) Al Hafoor Suite [ao88] 0.20020 0.41900 0.512600 7.9 0.0015 8 0.554830 43.4 0.0078 3 7.7 Al Ays Group [ay187] 0.13440 0.42390 0.512791 8.1 0.0016 4 0.544316 30.6 0.0056 18 11.9 Mardabah Complex [CV192] 0.04990 0.71190 0.512591 9.7 0.0019 2 0.481763 45.0 0.0093 15 67.8 Hadn Formation [hn160] 0.07240 0.40860 0.512662 8.0 0.0016 6 0.472895 49.9 0.0105 2 27.8 Kawr Suite [kw43] 0.06970 0.41820 0.512537 8.0 0.0016 3 0.508105 23.2 0.0046 2 25.7 Bani Ghayy Group [MCR105] 0.14380 0.40380 0.512685 8.1 0.0016 5 0.483904 33.2 0.0069 4 13.2 Al Hafoor Suite [MD95] 0.18410 0.42240 0.512457 7.8 0.0015 3 0.478437 90.9 0.0190 23 11.1 Murdama Group [mu132] 0.06770 0.40180 0.512469 7.9 0.0016 4 0.450507 92.3 0.0205 23 32.3 Siham Group [si116] 0.05540 0.64020 0.512264 7.7 0.0015 3 0.473747 30.6 0.0065 4 56.8 At Ta'if Group [tfv02] 0.12770 0.61640 0.512514 7.8 0.0015 6 0.699700 48.7 0.0070 1 12.1 G2#21 [USGS Standard] 0.05180 0.61690 0.512258 8.6 0.0017 2 0.499907 30.8 0.0062 1 52.7 - 51.2±3.9 G2 Sm/Nd Spike F (n=11). UofA Av. 0.05451 0.68699 0.512266 8.7 - - 0.526271 32.4 - G2 [USGS] 55±6 Blank#1621 [Procedural] - 0.04823 - - - - 2 - - - 167 pg JNdi1#147 [Standard] - - 0.512094 8.5 0.0017 3 - - - - - JNdi1#147 [Standard] - - 0.512089 9.1 0.0018 6 - - - - - *Note University of Adelaide Finnigan MAT262 JNdi1 average =0.512085±9.5 JNdi1 Tanaka et al. (2000) - - 0.512115 7 - - (n=650). See methods for explaination
473 Table3 (continued): Sm isotopes of sampled country rocks and mafic autolith units from the Arabian Shield analysed by TIMS (Finnigan MAT262). Similarly as above (Table 3), 147Sm/149Sm is measured to calculate the concentration of Sm (µgg-1) in the sample, hence the amount of 147Sm in the spike. 152Sm/149Sm is measured to correct for fractionation caused by the mass spectrometer. 147Sm/144Nd is calculated from the measured concentrations of Sm and Nd in the sample. A more detailed explanation of this procedure is seen in Appendix a6. Analysed samples were run in conjunction with international standards (G2, USGS) to determine machine accuracy and reliability of results.
Outliers in 2σ test Outliers in 2σ test Unmixed Sample+Map Unit 147Sm/149Sm 1σ 1σ [%] 152Sm/149Sm 1σ 1σ [%] Sm(µgg-1) 147Sm/144Nd (20 values) (20 values) 143Nd/144Nd Al Hafoor Suite [ao88] 5.743701 0.0039003 0.0679 1 1.901669 0.0011713 0.0616 1 1.8 .512530 0.1384 Al Ays Group [ay187] 5.304033 0.0004731 0.0089 1 1.914344 0.0013050 0.0682 0 2.9 .512724 0.1474 Mardabah Complex [CV192] 5.372742 0.0011625 0.0216 1 1.916143 0.0011110 0.0580 0 12.9 .512537 0.1154 Hadn Formation [hn160] 5.110063 0.0005482 0.0107 0 1.903689 0.0017612 0.0925 0 5.5 .512610 0.1194 Kawr Suite [kw43] 5.186755 0.0027490 0.0530 1 1.896171 0.0012040 0.0635 0 5.7 .512477 0.1350 Bani Ghayy Group [MCR105] 4.610734 0.0030918 0.0671 0 1.923303 0.0043487 0.2261 0 3.1 .512630 0.1420 Al Hafoor Suite [MD95] 6.409263 0.0059502 0.0928 0 1.892201 0.0008821 0.0466 1 1.7 .512403 0.0918 Murdama Group [mu132] 4.865651 0.0011612 0.0239 0 1.901148 0.0013125 0.0690 0 6.2 .512421 0.1154 Siham Group [si116] 5.721040 0.0008695 0.0152 1 1.922484 0.0005860 0.0305 0 9.6 .512211 0.1026 At Ta'if Group [tfv02] 9.127484 0.0017181 0.0188 1 1.870917 0.0007938 0.0424 1 2.3 .512412 0.1151 G2#21 [USGS Standard] 7.765779 0.0013506 0.0174 0 1.892957 0.0012111 0.0640 0 6.9 .512220 0.0788 - 6.7±0.5 0.512201±20 0.0796 G2 Sm/Nd Spike F (n=11). UofA Av. 8.349698 - 0.0237 - 1.883186 - 0.0425 G2 [USGS] 7.2±0.7 Blank#1621 [Procedural] 38.127440 6.7584630 25.53 - -- - - 22.0 pg - 0.0802
474 Table3 (continued): Sr isotopes of sampled country rocks and mafic autoliths from the Arabian Shield analysed by TIMS (Finnigan MAT262).The amount of Sr in the powdered sample is determined using the Sr XRF concentrations (Appendix 5) and the sample weight (see above). Samples with ~<2g were analysed using a Rhenium filament. A more detailed explanation of this procedure is seen in Appendix a6. Analysed samples were run in conjunction with internal standards (SRM987, University of Adelaide) and international standards (G2, USGS) to determine machine accuracy and reliability of results respectively.
Outliers in 2σ test (100 Sample+Map Unit Sample Weight (g) Sr Weight (g) 87Sr/86Sr 1σ 1σ [%] 2σ 2σ [%] Sr (ppm) Rb (ppm) values) Al Hafoor Suite [ao88] 0.20020 91.03094 0.704720 62.1 0.0088 12.6 0.0018 3 454.7 16 Al Ays Group [ay187] 0.13440 31.70496 0.704543 55.2 0.0078 11.2 0.0016 3 235.9 13 Mardabah Complex [CV192] 0.04990 25.25439 0.704383 52.6 0.0075 10.8 0.0015 5 506.1 29 Hadn Formation [hn160] 0.07240 19.1498 0.708841 75.4 0.0106 15.5 0.0022 5 264.5 65 Kawr Suite [kw43] 0.06970 16.40041 0.705530 51.1 0.0072 10.6 0.0015 7 235.3 0.8 Bani Ghayy Group [MCR105] 0.14380 81.56336 0.703967 57.9 0.0082 11.9 0.0017 5 567.2 21 Al Hafoor Suite [MD95] 0.18410 188.5184 0.704789 51.2 0.0073 10.6 0.0015 6 1024 69 Murdama Group [mu132] 0.06770 59.97543 0.705698 62.3 0.0088 12.7 0.0018 4 885.9 60 Siham Group [si116] 0.05540 3.9057 0.772496 75.2 0.0097 15.5 0.0020 6 70.5 185 At Ta'if Group [tfv02] 0.12770 2.84771 0.715381 115.0 0.0161 25.6 0.0036 9 22.3 11 G2#21 [USGS Standard] 0.05180 24.7604 0.709770 53.6 0.0076 10.9 0.0015 4 478 - 0.709741 G2 Sm/Nd (n=11). UofA Av. - 58.0 0.0082 11.8 0.0017 - - - [G2 USGS] 0.709770±7 Blank#1621 [Procedural] - Spike F 0.11460 0.713658 - - - - - 808 pg - SRM987#407 *Note Finnigan Recommended 87Sr/86Sr 0.710239 53.6 0.0075 10.9 0.0015 3 - - SRM987#407 0.710232 59.5 0.0084 12.0 0.0017 1 - - SRM987#407 =0.710220-0.710260 0.710242 52.9 0.0074 10.8 0.0015 2 - - SRM987 [Standard] n=744 Adelaide University MAT262 0.710268 84.0 0.0118 17.2 0.0024 - - -
475 Table 4: Calculated model ages for Arabian Shield country rocks and mafic autoliths analysed by TIMS (Finnigan MAT262). Values were processed using a Sm-Nd isotopic spreadsheet (University of Adelaide) with 143Nd/144Nd CHUR (t=0): 0.512638; 147Sm/144Nd (t=0): 0.1966; 143Nd/144Nd DM (t=0): 0.513150 and 147Sm/144Nd DM (t=0): 0.2145 ratios taken from Goldstein et al. (1984). Model ages are calculated based on these ratio values. A more detailed explanation of this procedure is seen in Appendix a6. The assigned age of the mafic autoliths is assumed to be same as the weighted average age of the granitoids directly dated in Chapter 3.2. However, units such as the Al Ays group, Hadn Formation, Bani Ghayy, Murdama, Siham and At Ta’if Groups are not directly dated, so values obtained from Johnson (2006) are used. Calculated error values are 2σ, but are unreliable because the assigned age contained no error parameters. Aside from mafic autoliths, all suites not directly dated were assigned a default of ±10Ma.
Unmixed Age of Depleted Sample+Map Unit Nd µgg-1 147Sm/144Nd Sm µgg-1 Present Day ɛNd Age Ma (t) 143Nd/144Nd (t) ɛNd (t) CHUR (t) 87Sr/86Sr (t) 143Nd/144Nd Mantle (t) Al Hafoor Suite [ao88] .512530 7.7 0.1384 1.8 -2.11 636±4 0.511953±7 2.63±0.14 1240±11 283±16 0.703831 Al Ays Group [ay187] .512724 11.9 0.1474 2.9 1.67 700±10 0.512047±11 6.08±0.22 698±12 (-)266±19 0.703119 Mardabah Complex [CV192] .512537 67.8 0.1154 12.9 -1.97 525.6±4.7 0.512149±7 3.49±0.14 942±9 190±11 0.703145 Hadn Formation [hn160] .512610 27.8 0.1194 5.5 -0.55 598±10 0.512142±10 5.37±0.19 865±9 55±12 0.702814 Kawr Suite [kw43] .512477 25.7 0.1350 5.7 -3.14 611.7±6.5 0.511936±8 1.68±0.16 1288±10 399±15 0.705447 630±10 0.512045±11 4.27±0.22 1090±11 21±17 0.703062 Bani Ghayy Group [MCR105] .512630 13.2 0.1420 3.1 -0.14 620±10 0.512054±11 4.20±0.22 1090±11 21±17 - Al Hafoor Suite [MD95] .512403 11.1 0.0918 1.7 -4.57 636±4 0.512021±6 3.95±0.13 927±7 342±9 0.703144 Murdama Group [mu132] .512421 32.3 0.1154 6.2 -4.22 630±10 0.511945±10 2.33±0.19 1119±9 406±11 0.704010 750±10 0.511707±9 0.70±0.18 1276±8 691±10 0.707962 Siham Group [si116] .512211 56.8 0.1026 9.6 -8.32 685±10 0.511751±9 (-)0.09±0.18 1131±8 424±10 - 840±10 0.511778±10 4.36±0.19 1131±9 424±11 0.703585 At Ta'if Group [tfv02] .512412 12.1 0.1151 2.3 -4.42 815±10 0.511797±10 4.10±0.19 1131±9 424±11 -
476 Appendix 7: Zircon Rare Earth Element Geochemistry
477 Island Arc Magmatism (~950-750Ma) Pre-Arabian Shield Assembly
478 Table 1: Trace element data from Makkah Suite (dm) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.1, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Details of this procedure are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures. The symbol ‘MC’ donates the discrete zircon morphological group (Chapter 3.2.1a).
Sample Nist610a Nist610b Nist612a Nist612b Nist610c Nist610d REE1 MC1 REE2 MC1 REE3 MC1 REE4 MC1 REE5 MC3 REE6 MC3 REE7 MC3 REE8 MC3 REE9 MC3 Nist610e Nist610f dm01a Na23 95108 95072 99258 91180 93836 97257 992.93 1285 1414 1847 845.58 1906 1345 1501 1637 95367 96910 Mg24 444.02 437.45 57.90 35.11 456.24 498.58 28.34 169.32 234.14 587.49 41.54 6.40 0.00 43.25 182.75 500.79 447.50 Al27 9880 10409 9306 8418 9743 9741 60.21 402.02 136.62 700.30 67.43 99.81 87.83 97.25 350.62 10160 10172 Si29 328329 328329 335917 335917 328329 328329 151965 151965 151965 151965 151965 151965 151965 151965 151965 328329 328329 P31 359.51 501.68 437.53 292.91 564.29 519.31 726.28 2554 3967 2818 484.73 2961 4048 1184.78 4651 2525.54 2177.91 K39 532.30 506.77 115.41 97.95 391.09 526.70 111.28 153.52 160.46 131.16 102.64 158.38 143.67 136.40 326.97 512.32 478.37 Ca43 89244 83220 69432 66031 71460 88016 5137 8319 15361 7881 7049 8753 8748 13281 11348 81325 82646 Ti49 526.15 475.93 17.56 34.30 436.74 505.37 24.57 135.35 24.68 20.54 9.80 0.00 21.44 22.75 79.94 506.88 545.00 Fe57 464.41 408.80 103.31 100.29 373.51 292.96 81.80 1097 768.04 1286 62.71 0.00 46.32 507.15 424.78 1415.02 682.64 Rb85 424.04 413.65 33.53 33.81 434.38 459.73 0.00 0.35 0.46 0.18 0.21 0.37 0.09 0.23 0.45 430.39 433.83 Sr88 484.67 484.73 76.12 67.55 501.83 515.34 0.14 0.35 0.07 0.80 0.35 0.05 0.05 0.18 0.00 494.95 518.43 Y89 440.03 434.34 30.25 27.64 458.38 471.30 1940 1842 2185 1183 2218 587 269 1405 1115 459.40 466.09 Zr90 425.51 420.49 27.49 27.39 446.86 469.55 559277 497813 561732 535072 551862 546353 513278 593987 499893 442.11 449.80 Nb93 402.38 406.74 30.92 29.37 424.54 446.73 2.65 1.95 2.39 1.33 2.22 1.03 0.90 1.79 1.76 418.85 430.42 La139 425.53 425.63 31.28 31.05 473.10 496.59 0.05 0.05 0.05 0.03 0.07 0.01 0.02 0.07 0.04 455.07 462.11 Ce140 417.25 415.13 35.63 35.20 462.48 485.30 43.85 35.32 41.55 20.50 51.38 10.70 5.09 28.14 21.11 439.44 457.31 Pr141 401.03 395.37 32.41 31.70 444.86 463.19 0.13 0.33 0.33 0.20 0.45 0.07 0.02 0.25 0.21 425.39 436.84 Nd146 401.98 392.39 30.00 29.89 448.67 467.07 2.42 5.10 5.36 3.06 7.06 1.12 0.25 3.98 3.52 429.71 434.94 Sm147 420.81 408.38 30.39 30.88 472.46 486.73 5.05 8.47 9.76 4.97 12.13 1.81 0.55 7.34 5.73 451.94 457.19 Eu153 426.93 421.24 31.63 31.69 482.74 496.67 2.80 4.39 4.83 2.72 6.48 0.97 0.30 3.55 2.74 460.08 462.55 Gd157 388.58 381.60 28.62 28.52 439.48 455.58 29.88 38.82 43.27 23.32 53.59 9.10 3.22 31.55 22.81 423.64 419.13 Tb159 407.99 403.09 30.17 29.34 465.85 478.49 11.45 13.21 15.16 8.19 18.07 3.52 1.41 11.24 8.01 444.67 444.86 Dy163 393.84 384.68 27.58 27.15 447.80 464.73 156.64 162.30 189.10 101.02 213.19 45.30 19.29 134.45 95.63 429.46 427.04 Ho165 414.43 404.77 29.57 29.33 470.19 490.75 67.16 62.69 73.95 39.48 79.04 18.90 8.70 52.33 37.14 451.40 452.10 Er166 390.71 386.59 28.30 27.61 444.25 463.47 341.14 296.32 346.51 188.45 362.98 94.82 45.91 245.63 179.12 427.02 430.42 Tm169 384.46 382.20 27.70 27.33 438.62 454.73 92.06 75.28 87.15 48.97 92.19 25.79 13.14 62.00 47.23 421.15 425.97 Yb172 420.57 419.54 30.97 30.39 484.12 499.36 1125 872.55 1014 588.67 1070 317.98 168.27 724.45 577.50 462.97 467.03 Lu175 395.60 393.96 28.77 27.81 460.04 470.73 199.76 142.81 166.03 97.76 176.17 55.27 29.98 119.07 97.24 439.27 439.57 Hf178 379.21 378.62 28.18 26.63 442.13 455.40 6735 7065 7759 7525 7704 8392 9147 9271 7108 423.42 420.49 Pb208 376.44 367.52 38.17 37.36 438.06 446.93 25.39 18.19 21.17 10.10 26.56 3.44 1.38 13.42 10.90 400.27 421.01 Th232 405.28 401.83 29.33 29.34 480.71 491.82 321.43 224.29 271.09 116.04 344.08 43.02 14.70 174.44 137.36 454.85 450.93 U238 410.87 409.55 36.78 36.69 486.01 499.72 367.67 263.77 319.23 161.03 290.96 83.26 44.47 217.07 194.79 455.47 457.79
479 Table 1 (continued): Trace element data from Makkah Suite (dm) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.1, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Details of this procedure are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures. The symbol ‘MC’ donates the discrete zircon morphological group (Chapter 3.2.1a).
Sample REE10 REE11 REE12 REE13 REE14 REE15 REE16 REE17 Nist610g Nist610h Nist612c Nist612d Nist610i Nist610j Nist610k Nist610l dm01a MC2 MC2 MC3 MC3 MC2 MC2 MC2 MC2 Na23 96910 96449 96971 109210 96101 90063 1325 1348 815.15 895.89 1078 1115 1671 1200 95379 96482 Mg24 447.50 490.93 30.58 63.30 384.11 527.83 501.88 69.12 3.29 50.97 52.75 0.00 47.57 77.58 483.23 456.27 Al27 10172 9664 9086 9179 10237 9814 482.35 90.77 66.05 726.80 71.46 68.57 771.28 128.58 10224 9851 Si29 328329 328329 335917 335917 328329 328329 151965 151965 151965 151965 151965 151965 151965 151965 328329 328329 P31 2178 3058 3017 3686 3423 2366 1894 2756 567.21 638.77 865.81 1055.93 813.93 3423 5964 6597 K39 478.37 540.90 176.71 207.21 455.32 421.77 214.52 149.37 104.75 115.22 121.15 126.28 126.13 135.42 575.63 420.04 Ca43 82646 81091 66243 59290 86897 76607 8235 12389 4884 11778 9434 15985 6716 12531 86058 78658 Ti49 545.00 517.19 47.29 0.00 309.71 250.78 54.23 0.00 25.84 10.91 15.12 42.98 26.32 43.08 468.22 493.77 Fe57 682.64 762.39 389.97 625.67 435.97 553.37 376.83 301.13 17.67 2043 332.15 124.35 420.89 285.14 524.30 495.85 Rb85 433.83 445.84 29.25 37.94 427.52 412.75 0.80 0.00 0.04 0.22 0.23 0.00 0.00 0.61 437.92 430.73 Sr88 518.43 496.84 67.87 72.06 495.52 472.93 0.91 0.15 0.12 0.51 0.31 0.16 4.15 1.44 508.02 496.33 Y89 466.09 452.78 27.92 31.89 444.98 418.03 1099 668 2078 1077 915.57 134.34 1346 3059 464.10 449.74 Zr90 449.80 449.43 31.02 30.30 438.29 412.24 530786 501022 537545 507936 571076 395605 483412 497456 450.31 439.80 Nb93 430.42 424.72 30.90 32.66 415.38 400.78 0.97 1.18 2.34 1.94 1.37 0.66 1.58 3.32 425.80 420.32 La139 462.11 462.08 32.62 34.04 462.70 441.31 0.05 0.01 0.06 0.17 0.04 0.04 0.03 0.20 464.86 454.38 Ce140 457.31 455.63 35.86 37.75 451.34 430.43 18.30 12.04 42.08 22.60 21.92 2.42 32.39 69.01 454.05 446.16 Pr141 436.84 433.67 32.78 34.56 433.59 415.48 0.21 0.05 0.16 0.27 0.17 0.04 0.37 0.80 435.52 427.99 Nd146 434.94 432.41 30.88 32.01 438.72 415.84 3.06 0.70 2.58 2.67 2.86 0.46 6.23 11.94 434.84 430.14 Sm147 457.19 447.35 31.63 34.24 456.79 436.32 5.21 1.53 5.25 3.11 4.42 0.45 8.28 16.98 455.00 449.98 Eu153 462.55 464.83 31.69 33.65 468.37 447.89 2.50 0.97 2.92 1.73 2.19 0.32 3.96 8.54 463.80 461.04 Gd157 419.13 425.21 28.35 28.78 424.46 404.99 22.83 9.54 31.95 15.99 17.24 2.27 30.36 64.96 421.12 422.72 Tb159 444.86 448.67 29.99 31.76 448.20 424.09 7.69 3.64 12.40 6.29 6.32 0.83 10.31 22.03 449.42 441.72 Dy163 427.04 429.77 27.44 29.81 433.73 410.43 93.23 50.58 166.53 86.41 77.17 10.74 121.09 257.35 431.69 425.54 Ho165 452.10 451.08 29.74 31.37 456.22 433.59 36.26 21.91 70.50 37.74 31.67 4.56 45.99 99.20 453.60 449.37 Er166 430.42 426.92 28.29 29.86 432.75 409.94 171.65 114.34 349.96 189.69 159.58 22.77 222.75 483.21 430.72 425.62 Tm169 425.97 420.41 28.17 29.40 426.59 402.97 43.54 31.96 89.02 50.26 43.35 6.27 60.17 130.75 424.44 420.60 Yb172 467.03 463.05 31.61 32.97 469.73 441.05 512.70 403.73 1024 595.44 531.06 79.93 733.38 1599 468.41 460.44 Lu175 439.57 434.70 27.78 30.00 440.79 415.37 85.90 71.49 171.69 102.57 94.76 14.85 120.45 270.69 442.85 432.96 Hf178 420.49 418.11 27.81 29.91 422.18 400.95 7439 6987 7606 8118 8557 5298 6682 5938 424.88 416.30 Pb208 421.01 420.79 38.25 41.80 419.24 403.10 8.67 4.40 23.78 11.59 9.32 1.10 12.62 32.70 419.68 408.20 Th232 450.93 450.17 30.00 31.72 459.89 436.03 105.33 56.01 303.61 149.93 111.98 12.97 148.41 416.39 456.70 448.17 U238 457.79 457.13 37.34 39.46 469.45 446.02 141.35 110.61 358.22 201.28 149.30 31.05 183.08 427.00 462.84 452.60
480 Syncollisional Magmatism (~736-636 Ma) Arabian Shield Microplate Accretion and Suture Formation
481 Table 2: Trace element data from the Shufayyah Complex (su) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.2, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Details of this procedure are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures. The symbol ‘MC’ donates the discrete zircon morphological group (Chapter 3.2.1b).
Sample Nist610a Nist610b Nist612a Nist612b Nist610c Nist610d REE1 MC1 REE2 MC1 REE3 MC1 REE4 MC1 REE5 MC3 REE6 MC3 REE7 MC3 REE8 MC3 Nist610e Nist610f su216 Na23 95594 96085 95193 95539 92652 92735 53.18 113.02 57.19 94.58 121.42 42.62 70.96 171.24 96666 95739 Mg24 473.42 463.9 56.78 55.5 446.35 439.7 6.83 9.7 98.12 12.11 10.16 81.83 19.5 740.28 464.55 485.76 Al27 10166 9971 9636 9255 9586 9638 29.06 168.66 156.53 60.62 239.65 175.98 198.07 1078 10142 10209 Si29 328329 328329 335917 335917 328329 328329 151965 151965 151965 151965 151965 151965 151965 151965 328329 328329 P31 312.31 388.91 35.25 31.31 336.96 373.68 399.8 801.9 540.75 349.83 575.2 520.19 491.99 460.54 333.11 336.35 K39 482.48 473.44 61.55 62.43 475.91 477.63 24.38 37.25 16.28 15.1 14.94 71.76 21.07 91.97 493.32 490.8 Ca43 81876 80450 81129 83428 80507 80945 223.12 1614 569.78 845.44 1414 1683 641.43 364.35 82307 82597 Ti49 417.3 440.85 34.33 36.34 418.15 445.87 14.15 12.62 15.35 10.38 18.75 525.75 19.44 26.53 433.95 435.88 Fe57 453.2 431.88 113.2 147.16 452.93 463.76 53.47 286.95 313.74 176.25 536.95 834.21 116.29 1398 443.52 475.83 Rb85 419.51 393.49 31.2 31.52 438.94 437.4 0.103 0.169 0.186 0.17 0.162 0.199 0.273 0.404 435.72 431.71 Sr88 482.7 457.86 68.47 71.64 505.62 505.55 0.291 3.94 0.947 0.234 7.33 1.27 6.64 2.84 501.43 498.53 Y89 433.94 414.92 30.98 32.99 458.15 464.93 1659.08 2348 2033 1048 2777 1137 3770 2271 450.69 449.65 Zr90 421.77 404.08 32.59 33.96 448.7 453.74 513093 493588 544520 459317 513307 561849 589736 536389 426.47 452.29 Nb93 404.48 387.04 31.46 32.96 427.62 432.3 0.98 3.27 1.366 0.726 3 1.43 4.69 4.22 420.73 418.79 La139 446.33 413.02 32.79 34.38 467.32 472.31 0.66 4.01 0.661 0.303 2.33 2.06 5.29 0.526 460.6 457.75 Ce140 438.49 402.3 34.66 36.39 457.56 462.86 10.12 60.16 14.7 6.29 65.2 14.77 232.44 14.07 452.16 447.56 Pr141 423.12 384.35 31.91 33.39 435.83 441.08 0.38 2.29 0.439 0.109 1.88 0.796 5.64 0.405 435.62 431.77 Nd146 419.75 381.45 31.02 31.68 433.26 440.48 3.91 16.11 4.62 1.12 14.09 5.84 44.69 4.1 435.77 436.3 Sm147 438.5 397.99 31.38 33.17 454.4 460.4 6.98 9.69 7.45 2.11 11.16 4.32 25.14 6.83 458.15 453.73 Eu153 453.37 410.32 31.16 33.11 466.68 470.49 1.46 1.72 1.236 0.443 1.83 0.64 3.03 1.282 469.68 463.58 Gd157 407.77 370.11 28.64 30.66 424.01 430.82 37.09 38.99 40.96 14.71 46.23 20.27 76.74 37.59 427.83 421.64 Tb159 436.56 392.99 31.12 32.75 448.88 456.18 13.24 14 14.75 6.09 16.98 7.75 26.02 14.38 450.64 443.8 Dy163 418.6 376.08 28.69 30.78 429.58 437.17 161.92 183.59 184.46 82.09 220.06 101.33 320.01 183.82 433.38 430.46 Ho165 445.22 397.49 30.96 32.65 455.21 462.32 59.82 75.56 71.07 34.31 89.86 40.09 126.95 74.53 457.62 451.03 Er166 420.3 375.38 28.91 31 427.58 440.43 259.35 366.33 320.16 164.93 434.32 186.38 589.72 354.12 432.03 429.95 Tm169 417.29 371.36 28.92 30.66 423.15 432.52 59.73 84.55 73.52 38.17 100.23 42.54 133.71 80.72 427.51 422.97 Yb172 456.15 405.39 32.11 33.86 461.78 471.48 624.43 842.07 753.28 379.69 997.27 431.29 1314 809.24 472.12 465.57 Lu175 430.42 384.36 29.76 31.2 439.08 448.22 88.61 167.15 120.73 73.57 196.89 73.09 243.52 154.71 441.79 437.51 Hf178 407.99 361.96 29.02 30.95 422.31 429.29 8905 9745 9885 8359 10328 11103 12305 10331 425.35 420.89 Pb208 413.46 360.01 33.17 36.98 411.01 417.91 2.68 8.79 5.36 1.48 14.82 3.2 20.34 4.65 421.27 422.68 Th232 445.75 390.45 30.53 32.88 461.31 470.56 42.06 118.5 92.98 19.75 325.83 50.78 464.59 92.82 458.69 450.23 U238 452.88 396.47 32.29 35.25 469.09 474.6 111.02 402.55 264.42 73.44 903.09 127.29 869.55 557.88 464.68 458.63
482 Table 2 (continued): Trace element data from the Shufayyah Complex (su) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.2, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Procedure details are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures. The symbol ‘MC’ donates the discrete zircon morphological group (Chapter 3.2.1b).
Sample Nist610g Nist610h Nist612c Nist612d Nist610i Nist610j REE9 MC2 REE10 MC2 REE11 MC2 REE12 MC2 REE13 MC2 REE14 MC2 REE15 MC2 Nist610k Nist610l su216 Na23 95739 94626 98468 96940 96168 94463 100.36 145.70 193.07 75.96 71.05 71.78 50.77 96283 94181 Mg24 485.76 468.51 55.27 61.44 460.36 456.49 50.75 57.25 99.45 10.53 418.23 38.56 21.14 478.15 456.94 Al27 10209 9961 9942 9549 9980 10083 105.80 157.70 602.06 82.17 1143 118.02 54.53 10048 9948 Si29 328329 328329 335917 335917 328329 328329 151965 151965 151965 151964 151965 151965 151965 328329 328329 P31 336.35 320.90 98.51 31.51 347.38 349.55 651.54 374.38 549.52 475.58 310.98 367.67 377.38 377.58 307.90 K39 490.80 490.88 58.94 66.45 496.23 483.78 134.00 214.03 373.61 36.83 7.68 19.86 45.63 483.01 486.32 Ca43 82597 82666 79764 78511 80467 81406 144.90 856.78 902.26 806.49 1403 742.71 313.60 83738 80508 Ti49 435.88 436.42 44.07 40.04 442.48 424.76 20.24 85.87 33.13 94.18 24.74 20.06 17.38 439.84 428.65 Fe57 475.83 507.98 135.26 145.75 454.80 475.63 151.56 538.58 1928 132.56 1130 438.30 77.77 451.88 449.81 Rb85 431.71 433.01 33.64 32.06 426.20 423.07 0.41 0.55 1.28 0.30 0.22 0.11 0.09 433.44 433.41 Sr88 498.53 501.77 74.37 71.20 494.61 492.44 0.78 0.33 7.18 1.07 0.71 0.34 0.50 502.11 495.08 Y89 449.65 449.84 34.86 32.18 446.86 447.56 2446 2618 4105 1353 1994 2183 1516 453.06 448.57 Zr90 452.29 449.26 35.08 32.88 438.25 436.19 516575 566426 460214 529040 548240 492607 534088 438.87 441.01 Nb93 418.79 423.23 33.85 32.71 416.49 416.19 1.59 1.05 2.85 0.88 0.78 1.18 1.47 421.58 418.97 La139 457.75 461.75 35.73 34.12 451.16 450.84 0.50 0.64 2.30 1.26 0.03 0.07 0.47 460.96 458.15 Ce140 447.56 453.44 37.84 36.22 442.48 439.29 23.29 16.97 62.46 9.86 7.55 17.40 15.24 449.74 450.59 Pr141 431.77 433.49 35.84 33.43 424.29 423.87 0.32 0.36 1.50 0.57 0.18 0.25 0.29 432.27 431.23 Nd146 436.30 435.64 34.80 32.83 427.18 420.94 3.90 6.00 13.42 4.52 3.36 2.83 3.09 434.79 431.34 Sm147 453.73 454.89 36.97 33.82 445.96 441.99 6.87 11.22 15.31 5.40 7.29 5.65 4.76 453.77 451.70 Eu153 463.58 465.47 35.72 33.66 456.03 452.46 1.32 2.03 2.17 0.92 1.40 0.96 0.97 465.65 461.45 Gd157 421.64 424.46 34.14 31.29 414.36 411.02 42.89 60.35 77.05 26.71 41.10 32.81 26.97 425.99 418.95 Tb159 443.80 446.82 34.68 32.84 438.27 434.04 15.76 21.41 29.07 9.62 14.91 12.61 10.34 448.42 442.05 Dy163 430.46 430.64 32.46 30.90 421.89 419.84 212.69 255.04 366.64 121.37 180.23 168.76 135.85 431.62 425.20 Ho165 451.03 454.97 35.15 33.25 444.79 441.09 86.11 97.61 143.69 47.25 68.59 70.90 52.91 454.68 448.66 Er166 429.95 429.48 33.73 31.83 421.96 418.86 394.58 420.41 654.82 212.95 300.34 345.79 238.72 430.43 425.42 Tm169 422.97 424.43 33.15 31.24 414.78 411.97 86.29 93.11 146.20 47.06 64.10 79.82 58.35 425.08 419.92 Yb172 465.57 465.27 36.81 35.17 454.48 452.54 827.80 894.27 1385 459.06 600.77 793.91 616.07 467.83 461.02 Lu175 437.51 439.44 33.99 31.57 429.77 425.12 149.21 150.53 264.62 81.34 108.38 162.63 90.20 439.78 434.85 Hf178 420.89 421.41 32.57 30.51 413.89 408.37 9347 11676 10555 10036 9793 9793 9282 423.56 416.56 Pb208 422.68 419.19 38.48 37.35 410.93 403.23 9.72 7.84 32.43 2.23 2.79 5.53 4.51 418.38 412.33 Th232 450.23 454.86 34.61 33.08 446.44 439.59 150.40 97.41 447.19 35.85 42.40 81.46 64.52 456.98 449.97 U238 458.63 460.50 37.32 35.71 455.27 443.20 270.58 216.66 886.19 91.92 94.24 239.32 177.07 462.06 458.22
483 Table 3: Trace element data from the Jar-Salajah Complex (js) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.3, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Details of this procedure are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures. The symbol ‘MC’ donates the discrete zircon morphological group (Chapter 3.2.1c).
Sample REE1 REE2 REE3 REE4 REE5 REE6 REE7 REE8 REE9 REE10 Nist610g Nist610h Nist612c Nist612d Nist610i Nist610j Nist610k Nist610l js202 MC1 MC1 MC1 MC1 MC1 MC1 MC2 MC2 MC2 MC2 Na23 93184 96335 98731 102572 98116 98546 42.08 238.32 114.06 71.49 286.8 410.09 85.41 73.03 94.8 455.71 95390 95209 Mg24 455.85 464.59 61.65 61.91 473.32 472.22 19.98 54.45 31.52 2.07 61.89 59.93 17.92 328.1 4.31 3919.13 467.37 457.31 Al27 9836 10040 10678 10512 10204 10251 157.87 742.22 363.32 25.41 460.04 113.13 146.81 1096.86 34.42 6234.93 9966 9862 Si29 328329 328329 335777 335917 328329 328329 151964.6 151964.6 151964.6 151964.6 151964.5 151964.6 151964.6 151964.6 151964.6 151964.55 328329 328329 P31 320.56 340.49 48.56 66.25 390.17 391.33 252.63 324.36 973.94 368.26 297.98 429 835.15 1926.05 867.2 1180.21 339.79 342.96 K39 481.24 486.40 69.34 62.52 496.18 491.99 36.07 228.84 248.41 16.45 405.31 487.83 30.63 216.3 43.86 2591.3 484.84 484.84 Ca43 80311 82349 86346 85885 83451 85125 388.8 272.88 1598 753.41 884.47 1021.53 689.54 4359.71 1108.88 2743.6 81537 80144 Ti49 431.75 432.73 41.55 40.39 448.92 454.33 6.28 11.91 7.27 12.95 21.77 40.73 11 116.91 27.18 917.88 431.97 424.52 Fe57 414.74 472.17 393.16 446.03 581.24 351.60 340.78 568.23 313.4 59.28 619.46 691.77 242.74 1142.07 234.93 8031.91 470.06 473.89 Rb85 424.80 427.38 32.19 33.50 435.67 435.29 0.207 0.673 0.67 0.154 0.91 0.95 0.45 1.499 0.109 13.88 428.91 428.55 Sr88 494.01 491.29 75.07 74.61 498.03 500.06 0.291 1.237 0.54 0.21 0.86 2.45 0.96 9.77 1.28 21.08 495.93 494.48 Y89 446.75 452.49 38.77 37.20 455.87 460.27 3078.88 1297.68 6151.79 2277.82 3953.81 3467.71 5868.09 3502.76 3160.55 6169.5 446.44 443.83 Zr90 434.81 444.82 38.57 36.98 448.15 449.01 517966.8 486130.9 496347.8 528583.5 543621.5 431162.6 500117 431617.3 555934.3 402009.31 428.81 428.13 Nb93 413.95 418.84 35.66 34.62 423.14 425.42 1.61 0.958 0.83 0.94 1.12 6.73 1.99 5.11 2.99 10.06 415.89 414.95 La139 456.52 449.32 37.43 36.09 448.77 452.16 0.72 1.229 2.47 3.02 1.26 1.87 0.88 35.05 7.29 53.51 456.63 453.00 Ce140 446.90 435.16 37.20 38.00 436.37 440.20 8.99 10.62 11.37 11.11 9.1 23.07 24.62 213.48 28.32 406.88 447.79 446.00 Pr141 429.94 415.46 35.34 34.77 415.31 418.08 0.65 0.415 1.13 1.34 0.71 1.21 1.03 29.35 3.1 48.52 429.53 425.50 Nd146 431.10 413.30 34.66 33.13 413.72 419.49 8.6 2.94 15.48 11.34 10.62 9.35 13.39 182.07 20.86 311.17 429.42 426.31 Sm147 449.17 434.71 36.09 34.65 432.59 440.33 17.17 3.88 57.95 13.53 20.45 15.65 38.31 87.29 16.3 170.99 448.57 446.52 Eu153 460.76 440.55 35.17 34.51 440.34 445.81 4.3 0.575 65.81 3.19 5.73 1.55 6 5.65 2.06 10.7 458.92 457.89 Gd157 418.85 405.60 33.82 33.55 402.74 406.69 80.9 21.04 322.98 63.18 103.85 71.15 196.51 156.87 69.87 299.58 417.23 414.48 Tb159 443.19 425.67 36.35 34.71 424.08 429.46 27.57 8.07 99.75 21.47 35.3 26.61 63.06 39.08 24.84 76.27 439.02 439.19 Dy163 424.95 407.51 33.79 32.06 409.93 411.60 320.31 107.16 844.02 251.4 406.17 326.52 646.01 363.43 307.39 737.59 424.24 421.10 Ho165 449.69 430.08 37.19 35.39 430.46 433.57 115.09 44.32 223.43 89.42 148.17 123.2 212.73 114.7 116.6 223.5 445.77 443.82 Er166 423.67 407.59 34.79 33.34 409.14 410.76 474.98 212.04 779.39 369.08 628.39 546.67 843.95 472 505.82 878.19 423.44 421.09 Tm169 418.96 402.68 34.34 32.94 401.49 404.59 105.71 50.1 135.78 81.03 126.61 117.89 164.65 96.79 109.48 182.21 418.02 415.26 Yb172 460.61 436.88 37.33 36.04 439.03 441.19 1057.54 521.26 1140 811.67 1132.64 1091.24 1433.22 899.02 1031.3 1727.21 460.43 456.84 Lu175 433.53 413.28 35.10 33.59 415.36 419.03 147.83 95.3 191.15 112.95 204.3 200.15 251.51 171.58 174.77 279.23 433.57 429.28 Hf178 416.16 394.47 33.16 32.05 399.35 399.24 7775.84 9711.76 8927.18 8117.64 8397.95 8265.07 9537.16 9013.6 10460.09 8516.99 421.70 411.36 Pb208 413.76 389.26 34.72 36.35 386.61 386.44 4.6 2.43 5.24 3.29 4.82 11.92 8.67 8.52 6.89 30.25 414.95 411.61 Th232 449.77 425.87 35.34 33.63 428.64 430.19 78.9 36.09 73.81 42.95 70.97 128.1 152.94 306.04 111.8 722.47 452.35 445.36 U238 452.98 428.53 35.11 36.45 428.28 431.94 246.04 132.02 177.1 140.99 191.87 385.72 354.59 412.33 309.72 1003.69 462.63 456.03
484 Table 3 (continued): Trace element data from the Jar-Salajah Complex (js) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.3, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Procedure details are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures. The symbol ‘MC’ donates the discrete zircon morphological group (Chapter 3.2.1c).
Sample REE11 REE12 REE13 REE14 REE15 REE16 REE17 REE18 REE19 Nist610g Nist610h Nist612c Nist612d Nist610i Nist610j Nist610k Nist610l js202 MC3 MC3 MC3 MC3 MC3 MC3 MC3 MC3 MC3 Na23 95209 94834 95749 99905 95170 95418 310.33 27.95 178.5 20.11 74.92 7.46 19.59 89.1 8.1 95356 95000 Mg24 457.31 466.18 61.31 59.50 468.86 469.43 80.92 759.22 26.48 76.81 77.3 1.53 154.62 25.39 14.38 467.21 461.82 Al27 9862 9917 10393 10053 10151 10287 868.36 1476.71 164.8 222.34 272.63 1.34 402.09 351.32 42.34 9970 9952 Si29 328329 328329 335917 335917 328329 328329 151964.55 151964.55 151964.53 151964.55 151964.55 151964.55 151964.56 151964.55 151964.53 328329 328329 P31 342.96 337.44 57.34 58.62 353.56 341.33 488.49 663.96 649.24 431.33 381.52 307.05 302.12 369.16 357.44 339.26 343.81 K39 484.84 486.08 60.86 63.68 490.17 485.16 267.63 1119.16 125.93 102.12 65.22 2.69 57.98 164.22 56.52 489.04 482.64 Ca43 80144 81805 83938 83683 83269 83434 613.62 1146.86 770.02 142.78 496.93 83.87 107.07 310.7 165.56 81736 81269 Ti49 424.52 433.11 41.65 37.19 440.13 446.06 467.34 231.42 414.95 28.86 58.58 3.87 43.85 8.49 451.39 443.68 421.12 Fe57 473.89 523.12 342.50 399.29 377.38 363.56 744.34 1845.35 452.24 487.96 765.45 290.69 812.9 151.72 603.64 440.81 503.62 Rb85 428.55 434.59 31.87 33.07 431.59 432.29 0.825 5.15 0.37 0.645 0.232 0.294 0.563 0.9 0.392 432.54 429.00 Sr88 494.48 494.99 74.21 73.85 499.67 505.42 3.26 1.025 1.19 1.082 0.431 0.279 1.123 1.38 0.555 498.69 493.91 Y89 443.83 444.23 38.24 36.34 459.58 463.46 1325.05 1446.45 3471.6 2031.57 2149.56 1449.51 1303.46 2811.5 1200.91 451.82 443.29 Zr90 428.13 441.09 38.94 36.74 453.22 456.71 510322.34 498317.03 525227.75 483831.38 558409.94 508931 520698.75 539074.5 524079.13 443.35 427.06 Nb93 414.95 418.58 34.56 33.81 424.67 427.02 2.22 1.257 6.27 2.74 1.68 1.76 1.55 1.89 1.71 422.61 413.43 La139 453.00 453.82 37.31 36.64 462.85 464.96 2.91 1.61 3.59 3.08 1.09 0.0373 1.95 1.82 0.288 461.58 450.78 Ce140 446.00 446.44 38.23 37.35 448.23 451.85 24.74 12.66 25.27 40.88 8.79 10.4 19.49 14.61 9.59 454.10 440.88 Pr141 425.50 429.44 35.52 35.24 432.78 433.80 2.1 1.087 1.39 2.61 0.52 0.0367 1.287 1.19 0.178 436.44 422.05 Nd146 426.31 427.16 35.20 34.41 435.33 440.40 12.53 7.6 9.62 19.15 4.39 0.813 8.9 11.28 1.55 435.88 423.01 Sm147 446.52 447.06 37.26 36.27 455.12 459.53 8.62 6.31 11.35 13.85 7.9 2.55 7.03 17.02 2.5 457.25 441.23 Eu153 457.89 458.59 36.51 35.48 465.73 467.66 0.714 0.686 0.63 1.12 0.81 0.334 0.602 2.99 0.319 469.54 450.84 Gd157 414.48 415.43 35.16 34.44 429.04 429.21 25.8 24.51 65.83 41.87 43.19 18.03 23.82 71.56 15.57 425.24 411.08 Tb159 439.19 437.88 37.61 36.13 449.27 454.94 9.05 9.05 24.92 14.46 16.12 7.67 8.52 25.11 6.42 447.56 434.42 Dy163 421.10 421.02 34.94 34.21 434.24 438.59 115.76 116.97 317.02 180.08 204.11 109.23 106.71 289.07 89.84 430.26 418.88 Ho165 443.82 444.68 37.84 36.85 456.60 463.62 45.24 48.41 123.94 69.85 78.78 47.57 44.02 106.54 38.81 453.00 441.48 Er166 421.09 421.13 35.70 34.74 432.70 437.88 220.04 236.17 549.62 324.4 344.47 236.77 213.82 448.56 195.99 430.47 417.91 Tm169 415.26 415.23 35.58 34.32 426.65 431.49 53.69 55.01 115.2 77.02 77.49 56.87 49.72 100.15 47.14 424.87 411.95 Yb172 456.84 454.91 39.38 37.96 468.87 472.56 566.71 564.79 1041.86 806.86 749.66 601.48 515.08 963.19 495.33 467.29 452.38 Lu175 429.28 428.21 36.79 35.39 442.47 446.98 102.4 115.74 190.2 138.07 118.08 116.59 102.34 154.02 99.07 439.06 426.62 Hf178 411.36 411.02 35.58 35.14 422.83 426.53 9975.98 9926.27 10968.11 9530.51 10026.95 10349.97 10887.5 9254.8 10732.19 423.44 409.72 Pb208 411.61 417.33 37.80 37.62 411.70 408.89 6.73 2.38 8.74 6.79 4.78 2.47 3.07 4.76 2.32 417.75 410.20 Th232 445.36 444.65 37.70 35.65 454.24 461.49 92.31 37.65 136.47 113.63 55.99 41.79 41.57 143.75 35.84 456.77 441.95 U238 456.03 454.85 37.10 37.50 456.20 454.65 243.05 161.39 359.33 337.81 189.62 172.36 161.24 304.99 145.07 466.69 449.18
485 Table 4: Trace element data from the Subh Suite (sf) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.4, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Details of this procedure are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures.
Sample Nist610a Nist610b Nist612a Nist612b Nist610c Nist610d REE1 REE2 REE3 REE4 REE5 REE6 REE7 REE8 REE9 REE10 Nist610e Nist610f sf209 Na23 91942 95896 96184 98002 94534 94530 178.50 74.92 94.80 286.80 410.09 85.41 114.06 42.08 71.49 89.10 95308 95597 Mg24 463.80 466.85 59.28 55.30 451.48 452.14 26.48 77.30 4.31 61.89 59.93 17.92 31.52 19.98 2.07 25.39 464.79 475.63 Al27 9873 10024 9481 9602 9762 9783 164.80 272.63 34.42 460.04 113.13 146.81 363.32 157.87 25.41 351.32 10061 10121 Si29 328329 328329 335917 335917 328329 328329 151965 151965 151965 151965 151965 151965 151965 151965 151965 151965 328329 328329 P31 348.99 365.55 60.26 47.06 350.57 386.39 649.24 381.52 867.20 297.98 429.00 835.15 973.94 252.63 368.26 369.16 304.14 357.35 K39 496.56 484.74 69.59 59.39 470.55 477.77 125.93 65.22 43.86 405.31 487.83 30.63 248.41 36.07 16.45 164.22 499.82 481.22 Ca43 86810 78719 75010 81756 80190 81663 770.02 496.93 1109 884.47 1022 689.54 1598 388.75 753.41 310.70 82238 82283 Ti49 427.53 427.88 41.71 36.80 467.92 443.04 414.95 58.58 27.18 21.77 40.73 11.00 7.27 6.28 12.95 8.49 419.10 438.91 Fe57 489.65 486.32 253.11 231.84 525.98 393.37 452.24 765.45 234.93 619.46 691.77 242.74 313.40 340.78 59.28 151.72 461.01 448.86 Rb85 509.03 394.78 31.01 30.90 407.41 415.96 0.37 0.23 0.11 0.91 0.95 0.45 0.67 0.21 0.15 0.90 439.29 443.86 Sr88 595.91 453.77 65.11 68.70 474.16 481.24 1.19 0.43 1.28 0.86 2.45 0.96 0.54 0.29 0.21 1.38 507.34 510.55 Y89 541.46 408.47 30.23 31.27 438.11 438.86 3472 2150 3161 3954 3468 5868 6152 3079 2278 2812 457.57 458.16 Zr90 520.19 398.38 31.87 35.64 428.19 429.52 525228 558410 555934 543622 431163 500117 496348 517967 528584 539075 444.18 450.13 Nb93 505.40 380.40 29.48 31.42 403.40 409.48 6.27 1.68 2.99 1.12 6.73 1.99 0.83 1.61 0.94 1.89 426.94 428.27 La139 601.57 403.90 30.58 32.92 435.75 441.37 3.59 1.09 7.29 1.26 1.87 0.88 2.47 0.72 3.02 1.82 473.75 468.62 Ce140 592.93 395.90 32.86 35.04 422.82 427.79 25.27 8.79 28.32 9.10 23.07 24.62 11.37 8.99 11.11 14.61 465.24 461.73 Pr141 574.54 375.85 30.28 32.28 405.03 411.05 1.39 0.52 3.10 0.71 1.21 1.03 1.13 0.65 1.34 1.19 447.22 444.31 Nd146 575.65 371.44 29.01 31.10 403.52 408.31 9.62 4.39 20.86 10.62 9.35 13.39 15.48 8.60 11.34 11.28 449.83 446.17 Sm147 600.62 388.06 30.01 31.06 419.51 429.49 11.35 7.90 16.30 20.45 15.65 38.31 57.95 17.17 13.53 17.02 470.35 465.96 Eu153 627.14 399.33 29.39 31.99 432.50 437.95 0.63 0.81 2.06 5.73 1.55 6.00 65.81 4.31 3.19 2.99 483.87 476.93 Gd157 565.03 360.22 27.24 29.30 393.58 397.49 65.83 43.19 69.87 103.85 71.15 196.51 322.98 80.87 63.18 71.56 437.24 436.81 Tb159 603.39 382.50 29.09 31.27 419.51 421.50 24.92 16.12 24.84 35.30 26.61 63.06 99.75 27.57 21.47 25.11 462.70 458.84 Dy163 581.91 365.54 26.26 28.91 399.79 405.15 317.02 204.11 307.39 406.17 326.52 646.01 844.02 320.31 251.40 289.07 446.51 442.40 Ho165 618.99 386.54 28.86 31.58 425.78 428.02 123.94 78.78 116.60 148.17 123.20 212.73 223.43 115.09 89.42 106.54 469.55 466.34 Er166 584.77 365.03 27.31 29.99 399.88 405.85 549.62 344.47 505.82 628.39 546.67 843.95 779.39 474.98 369.08 448.56 445.43 442.33 Tm169 582.44 361.11 27.08 29.84 394.92 400.30 115.20 77.49 109.48 126.61 117.89 164.65 135.78 105.71 81.03 100.15 441.61 434.78 Yb172 640.56 393.76 29.78 32.64 431.26 435.34 1042 749.66 1031 1133 1091 1433 1140 1058 811.67 963.19 484.72 480.69 Lu175 605.76 372.29 27.85 30.19 410.76 415.70 190.20 118.08 174.77 204.30 200.15 251.51 191.15 147.83 112.95 154.02 455.73 450.05 Hf178 575.59 352.34 27.87 29.63 390.94 396.95 10968 10027 10460 8398 8265 9537 8927 7776 8118 9255 438.92 431.78 Pb208 592.69 353.00 32.10 34.27 373.37 386.54 8.74 4.78 6.89 4.82 11.92 8.67 5.24 4.61 3.29 4.76 439.43 433.10 Th232 649.64 380.65 28.92 31.19 425.83 430.45 136.47 55.99 111.80 70.97 128.10 152.94 73.81 78.85 42.95 143.75 473.85 467.27 U238 661.71 386.61 31.08 33.28 425.73 437.64 359.33 189.62 309.72 191.87 385.72 354.59 177.10 246.04 140.99 304.99 484.17 473.61
486 Post-Orogenic Magmatism (~636-600 Ma) Post-Arabian Shield Terrane Accretion
487 Table 5: Trace element data from the Kawr Suite (kw) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.5, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Details of this procedure are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures. The symbol ‘MC’ donates the discrete zircon morphological group (Chapter 3.2.1e).
Sample REE1 REE2 REE3 REE4 REE5 REE6 REE7 REE8 REE9 REE10 REE11 REE12 REE13 Nist610a Nist610b Nist612a Nist612b Nist610c Nist610d Nist610e Nist610f kw42 MC1 MC1 MC1 MC1 MC1 MC1 MC1 MC1 MC3 MC3 MC3 MC3 MC3 Na23 93591 96175 98987 95691 94408 95100 157.2 416.01 107.54 109.48 102.9 38.57 53.59 129.24 221.01 760.15 437.57 113.3 99.91 95183 95549 Mg24 467.48 466.94 56.33 55.22 457.10 443.92 9.07 321.15 16 86.86 26.02 58.71 5.05 44.78 2732.97 2015.56 24.41 16.21 26.66 480.66 466.45 Al27 9894 10053 9283 9178 9920 9699 36.38 708.22 86.22 286.88 109.21 193.82 67.06 329.13 2168.54 2289.86 249.76 265.17 136.95 10090 10125 Si29 328329 328329 335917 335917 328329 328329 151965 151965 151965 151965 151965 151965 151965 151965 151965 151965 151965 151965 151965 328329 328329 P31 292.90 345.89 51.08 67.81 386.73 400.01 270.59 218.01 417.9 424.59 405.28 250.17 189.46 2332.24 510.89 451.33 613.92 587.03 1845.34 323.41 318.48 K39 489.76 485.00 66.99 58.13 472.69 472.30 150.18 287.12 80.58 90.19 45.49 55.3 16.83 47.31 110.13 373.63 150.45 57.5 9.71 494.54 492.57 Ca43 81559 80519 78924 76287 80357 81462 244.58 494.86 779.86 434.58 625.8 467.02 221.97 7823.4 1628.86 1971.89 950.57 270.04 4736.18 82259 82702 Ti49 450.91 415.74 37.88 32.42 429.77 426.44 13.06 37.36 29.2 23.86 5.72 8.14 4.96 28.95 47.92 94.5 23.53 26.31 4.71 444.76 433.18 Fe57 450.29 432.36 284.60 313.88 559.28 521.28 144.14 761.46 161.26 420.16 209.36 337.15 63.88 160.08 3865.68 2809.34 273.7 184.48 292.86 393.53 474.58 Rb85 418.86 405.10 31.63 30.68 425.36 431.50 0.333 0.62 0.157 3.24 0.363 0.408 0.071 0.252 0.291 1.76 0.5 0.194 0.192 439.62 437.66 Sr88 484.58 464.56 68.49 70.93 496.51 497.33 0.244 4.15 1.65 4.77 1.82 1.35 1.94 10.17 10.05 23.41 18.62 7.77 2.76 508.06 503.09 Y89 438.86 419.96 30.53 31.71 450.01 451.29 962.27 2037.82 1397.28 4345.54 3045.34 1482.4 2176.65 1889.19 2116.27 4041.12 2885.62 2499.77 2446.35 456.93 455.72 Zr90 426.66 410.91 30.62 32.08 437.73 441.31 462915 411657 455258 491231 500877 547220 571366 575473 480078 457408 640539 576505 509764 455.45 447.09 Nb93 410.84 395.02 30.91 31.11 411.26 420.02 2.22 7 9.66 18.98 10.51 2.08 4.33 3.91 16.85 26.21 9.49 5.79 8.87 428.52 426.51 La139 448.16 421.87 31.69 32.89 451.22 454.05 1.46 16.1 2.64 6.24 11.82 3.83 4.43 48.41 17.26 91.51 20.34 33.24 48.78 474.12 469.41 Ce140 435.36 411.47 34.51 35.52 441.01 452.61 13.94 65.63 25.38 122.51 70.58 29.68 53.77 145 86.77 503.7 77.89 121.9 159.59 464.05 455.88 Pr141 421.19 391.21 31.58 32.38 424.77 425.38 0.6 10.21 2.69 8.15 6.9 2.65 3.26 20.55 13.89 65.17 12 21.79 22.6 449.38 442.20 Nd146 417.04 387.48 29.20 30.40 424.76 428.92 5.28 68.48 20.15 60.21 45.31 16.35 21.58 104.16 92.92 349.16 64.49 117.62 127.15 447.67 442.96 Sm147 435.19 405.82 30.61 31.73 444.83 449.18 6.49 47.22 19.35 57.19 34.56 16.33 23.03 58.78 58.32 129.19 45.82 73.75 49.03 467.13 462.64 Eu153 452.49 412.50 31.39 32.37 454.26 463.96 0.63 2.67 1.35 2.45 0.63 0.99 1.88 2.82 1.38 3.25 1.56 2.15 0.71 482.60 473.68 Gd157 406.42 379.17 27.85 29.61 409.56 418.92 26.61 98.56 56.69 156.07 112.56 41.63 68.03 98.78 102.9 203.58 93.12 117.07 93.76 438.79 431.72 Tb159 437.26 395.84 29.93 31.10 434.66 446.14 9.19 29.65 18.31 53.69 37.17 14.15 21.48 25.58 32.99 63.08 29.52 28.69 27.88 464.04 456.87 Dy163 419.94 377.94 27.74 28.27 419.19 427.87 103.3 290.89 190.95 556.95 398.94 153.86 230.73 226.82 324.91 601.79 311.5 264.85 290.93 447.58 438.74 Ho165 442.69 401.72 29.84 31.31 442.83 451.23 36.81 86.23 59.09 172.05 126.78 54.72 79.42 67.85 93.67 170.33 103.84 84.01 94.62 472.40 462.89 Er166 418.13 378.90 28.33 28.90 421.80 424.40 152.05 321.73 226.13 660.64 471.17 239.3 327.12 268.57 359.71 638.54 449.87 357.67 384.3 447.92 438.31 Tm169 414.39 373.71 27.96 29.05 417.77 419.64 35.07 63.18 48.47 141.39 96.81 57.9 75.68 60.56 71.59 139.59 105.75 83.64 78.55 442.23 432.03 Yb172 456.16 407.82 30.94 32.21 452.50 458.92 358.49 553.99 482.57 1329.34 880.58 652.96 803.45 648.27 630.14 1374.31 1098.52 893.29 712.14 486.73 477.56 Lu175 426.52 388.24 28.73 29.92 430.46 434.29 49.45 90.44 61.25 182.13 113.04 89.86 109.79 89.77 100.19 180.6 169.07 138.21 115.38 457.69 449.12 Hf178 406.67 368.78 27.88 29.44 412.19 414.09 8032.11 8825.3 9742.53 9717.21 8251.35 10992.8 10345.9 10288.8 14818.4 12396.3 13475.4 11803.8 11813.9 440.52 428.83 Pb208 406.41 364.12 35.14 35.77 401.98 409.49 4.65 11.46 15 47.44 13.63 24.88 49.49 38.76 38.23 41.15 60.76 58.26 13.52 439.50 429.31 Th232 442.17 394.74 29.61 30.89 447.70 454.45 64.89 78.32 98.78 879.17 207.05 361.6 882.77 545.67 308.02 580.8 811.51 806.5 249.36 477.07 464.58 U238 447.52 399.93 35.06 35.99 450.94 465.07 226.41 3061.09 494.64 1802.09 634.03 1179.93 1787.81 1116.73 1066.12 2773.2 2568.43 2731.09 745.83 483.82 473.70
488 Table 5 (continued): Trace element data from the Kawr Suite (kw) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.5, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Details of this procedure are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures. The symbol ‘MC’ donates the discrete zircon morphological group (Chapter 3.2.1e).
Sample REE14 REE15 REE16 REE17 REE18 REE19 REE20 REE21 REE22 REE23 REE24 REE25 REE26 Nist610g Nist610h Nist612c Nist612c Nist610i Nist610j Nist610k Nist610l kw42 MC3 MC2 MC2 MC2 MC2 MC2 MC2 MC2 MC2 MC2 MC2 MC2 MC2 Na23 93591 96175 98987 95691 94408 95100 206.47 146.98 114.11 66.71 134.51 62.76 102.38 91.11 62.49 31.93 563.37 602.79 278.68 95183 95549 Mg24 467.48 466.94 56.33 55.22 457.10 443.92 16.86 482.94 10.42 10.07 22.19 13.25 39.1 6.18 12.44 3.99 2667.88 508.72 136.64 480.66 466.45 Al27 9894 10053 9283 9178 9920 9699 172.01 1243.67 258.66 105.39 260.83 170.57 241.86 41.87 41.1 40.16 2729.35 508.05 466.04 10090 10125 Si29 328329 328329 335917 335917 328329 328329 151965 151965 151965 151965 151965 151965 151965 151965 151965 151965 151965 151965 151965 328329 328329 P31 292.90 345.89 51.08 67.81 386.73 400.01 648.83 892.94 468.98 188.3 366.78 226.97 1086.12 211.36 901.3 397.26 1257.74 1423.28 407.56 323.41 318.48 K39 489.76 485.00 66.99 58.13 472.69 472.30 46.78 143.87 87.77 6.94 54.25 35.35 94.83 14.93 62.95 6.36 535.31 652.13 176.54 494.54 492.57 Ca43 81559 80519 78924 76287 80357 81462 1093.58 2170.33 1048.99 394.76 970.37 204.34 3597.55 220.2 2330.01 721.36 4338.6 3953.42 798.81 82259 82702 Ti49 450.91 415.74 37.88 32.42 429.77 426.44 11.38 80.21 9.33 20.75 34.83 23.41 16.05 6.12 8.48 5.17 81.44 38.09 26.06 444.76 433.18 Fe57 450.29 432.36 284.60 313.88 559.28 521.28 1673.94 1247.76 148.49 195.74 237.11 2071.69 215.59 75.72 132.59 44.03 3248.81 815.78 655.87 393.53 474.58 Rb85 418.86 405.10 31.63 30.68 425.36 431.50 0.73 0.436 0.88 0.063 0.412 0.149 0.153 0.102 0.127 0.111 1.24 1.41 0.91 439.62 437.66 Sr88 484.58 464.56 68.49 70.93 496.51 497.33 5.94 20.19 5.11 4.86 8.3 3.27 5.75 1.36 1.35 1.83 21.1 7.36 4.06 508.06 503.09 Y89 438.86 419.96 30.53 31.71 450.01 451.29 2188.61 5947.22 1568.7 1403.49 5578.67 1499.16 1569.97 1492.59 941.31 1448.88 4816.09 2509.85 2690.13 456.93 455.72 Zr90 426.66 410.91 30.62 32.08 437.73 441.31 600056 501395 549103 470884 484153 585193 619023 549113 493989 570169 469881 429784 486548 455.45 447.09 Nb93 410.84 395.02 30.91 31.11 411.26 420.02 5.98 30.27 4.93 9.06 13.38 3.9 3.55 4.69 4 3.37 21.89 11.72 13.25 428.52 426.51 La139 448.16 421.87 31.69 32.89 451.22 454.05 24.45 25.02 19.37 339.09 7.23 10.38 24 3.79 14.06 7.28 22.39 13.58 36.45 474.12 469.41 Ce140 435.36 411.47 34.51 35.52 441.01 452.61 76.92 185.23 79.31 625.82 95.78 101.84 79.62 58.03 43.82 33.9 156.25 86.65 143.19 464.05 455.88 Pr141 421.19 391.21 31.58 32.38 424.77 425.38 10.08 28.76 11.28 79.41 11.2 7.23 11.29 2.64 5.43 3.05 24.21 12.91 19.15 449.38 442.20 Nd146 417.04 387.48 29.20 30.40 424.76 428.92 51.08 192.03 59.2 373.54 83 40.75 61.28 14.87 29.53 16.68 156.27 86.07 112.51 447.67 442.96 Sm147 435.19 405.82 30.61 31.73 444.83 449.18 30.43 160.84 37.32 86.04 97.77 28.61 35.8 11.95 12.88 11.21 121.99 51.59 60.47 467.13 462.64 Eu153 452.49 412.50 31.39 32.37 454.26 463.96 1.17 3.95 1.22 1.65 4.36 1.12 1.13 0.61 0.67 0.7 2.74 1.39 1.89 482.60 473.68 Gd157 406.42 379.17 27.85 29.61 409.56 418.92 64.61 310.76 64.28 93.21 247.22 51.08 59.95 32.85 32.07 31.99 253.65 105.28 115.68 438.79 431.72 Tb159 437.26 395.84 29.93 31.10 434.66 446.14 20.63 110.79 18.73 22.26 85.37 14.8 16.44 11.5 10.23 11.01 86.99 36.33 38.18 464.04 456.87 Dy163 419.94 377.94 27.74 28.27 419.19 427.87 217.2 1080.49 178.51 202.19 858.38 151.56 160.46 136.34 109.88 129.03 848.96 366.82 387.83 447.58 438.74 Ho165 442.69 401.72 29.84 31.31 442.83 451.23 76.49 288.67 56.43 59.31 244.73 52.16 54.83 51.71 36.42 49.49 228.72 110.9 116.8 472.40 462.89 Er166 418.13 378.90 28.33 28.90 421.80 424.40 337.57 1019.12 233.86 223 879.35 230.61 238.35 238.96 147.83 233.21 805.14 419.33 452.46 447.92 438.31 Tm169 414.39 373.71 27.96 29.05 417.77 419.64 80.21 208.06 53.58 46.19 184.25 56.75 54.45 60.61 32.08 57.6 156.19 82.27 91.18 442.23 432.03 Yb172 456.16 407.82 30.94 32.21 452.50 458.92 864.18 1896.83 551.49 435.13 1736.13 632.07 567.82 691.68 319.28 640.39 1327.61 711.69 799.43 486.73 477.56 Lu175 426.52 388.24 28.73 29.92 430.46 434.29 132.49 234.3 85.42 62.53 207.79 96.08 97.46 104.62 45.08 102.11 190.41 112.22 133.08 457.69 449.12 Hf178 406.67 368.78 27.88 29.44 412.19 414.09 12048.9 12242.4 11051 11324.2 8918.67 10730.7 12287.5 11394.2 11583.7 10067.5 11382.7 10201.9 11014.9 440.52 428.83 Pb208 406.41 364.12 35.14 35.77 401.98 409.49 49.44 31.79 37.4 7.06 40.29 32.01 31.11 37.78 4.85 21.64 42.15 19.94 18.75 439.50 429.31 Th232 442.17 394.74 29.61 30.89 447.70 454.45 788.29 601.2 476.29 150.49 738.89 316.23 413.53 606.66 75.94 357.99 592.04 230.43 242.84 477.07 464.58 U238 447.52 399.93 35.06 35.99 450.94 465.07 2152.1 1406.77 1458.76 527.5 1500.01 1186.38 1334.38 1983.96 298.32 1220.93 1077.07 787.4 945.73 483.82 473.70
489 Table 6: Trace element data from the Al Hafoor Suite (ao) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.6, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Details of this procedure are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures.
Sample Nist610a Nist610b Nist612a Nist612b Nist610c Nist610d REE1 REE2 REE3 REE4 REE5 REE6 REE7 REE8 REE9 REE10 REE11 Nist610e Nist610f ao85 Na23 95512 96356 95094 95992 93190 93731 91.11 38.57 114.11 206.47 113.3 102.38 53.59 129.24 437.57 62.76 31.93 95500 95870 Mg24 471.86 469.65 56.8 56.52 446.65 445.73 6.18 58.71 10.42 16.86 16.21 39.1 5.05 44.78 24.41 13.25 3.99 475.41 468.73 Al27 10126 10000 9280 8813 9571 9683 41.87 193.82 258.66 172.01 265.17 241.86 67.06 329.13 249.76 170.57 40.16 10086 10192 Si29 328329 328329 335917 335917 328329 328329 151965 151965 151965 151965 151965 151965 151965 151965 151965 151965 151965 328329 328329 P31 305.36 338.25 57.24 41.31 396.83 373.64 211.36 250.17 468.98 648.83 587.03 1086 189.46 2332.24 613.92 226.97 397.26 334.77 324.7 K39 479.63 478.25 66.76 61.51 484.63 478.06 14.93 55.3 87.77 46.78 57.5 94.83 16.83 47.31 150.45 35.35 6.36 483.63 493.98 Ca43 81677 78979 76979 76015 80585 83899 220.2 467.02 1049 1094 270.04 3598 221.97 7823 950.57 204.34 721.36 84390 79805 Ti49 445.8 418.05 45.97 32.71 424.51 418.92 6.12 8.14 9.33 11.38 26.31 16.05 4.96 28.95 23.53 23.41 5.17 463.73 419.5 Fe57 442.5 409.26 136.9 125.17 499.95 472.4 75.72 337.15 148.49 1674 184.48 215.59 63.88 160.08 273.7 2071.69 44.03 451.17 454.16 Rb85 407.36 395.33 31.43 34.47 444.44 456.43 0.102 0.408 0.88 0.73 0.194 0.153 0.071 0.252 0.5 0.149 0.111 432.28 426.48 Sr88 470.89 454.68 67.58 70.62 517.14 523.61 1.36 1.35 5.11 5.94 7.77 5.75 1.94 10.17 18.62 3.27 1.83 499.41 491.5 Y89 426.71 413.38 31.94 31.27 464.74 476.16 1493 1482 1569 2189 2500 1570 2177 1889 2886 1499 1449 450.74 444.85 Zr90 410.41 400.48 31.5 30.45 462.23 476.11 549113 547220 549103 600056 576505 619023 571366 575473 640539 585193 570169 356.7 488.41 Nb93 396.16 385.32 31.4 31.54 436.48 444.27 4.69 2.08 4.93 5.98 5.79 3.55 4.33 3.91 9.49 3.9 3.37 419.65 414.07 La139 430.9 410.75 32.51 33.39 482.62 492.1 3.79 3.83 19.37 24.45 33.24 24 4.43 48.41 20.34 10.38 7.28 459.48 448.36 Ce140 422.05 401.81 35 36.83 472.11 482.72 58.03 29.68 79.31 76.92 121.9 79.62 53.77 145 77.89 101.84 33.9 450.06 438.72 Pr141 407.17 382.16 32.23 33.38 451.44 462.4 2.64 2.65 11.28 10.08 21.79 11.29 3.26 20.55 12 7.23 3.05 433.67 421.57 Nd146 404.57 378.4 30.37 31.42 449.42 461.18 14.87 16.35 59.2 51.08 117.62 61.28 21.58 104.16 64.49 40.75 16.68 435.51 424.68 Sm147 422.4 396.02 31.93 31.89 468.69 481.51 11.95 16.33 37.32 30.43 73.75 35.8 23.03 58.78 45.82 28.61 11.21 457.98 442.53 Eu153 436.3 407.28 31.22 32.62 482.16 495.9 0.61 0.99 1.22 1.17 2.15 1.13 1.88 2.82 1.56 1.12 0.7 467.43 452.17 Gd157 394.09 367.12 28.69 29.48 436.86 452.48 32.85 41.63 64.28 64.61 117.07 59.95 68.03 98.78 93.12 51.08 31.99 425.68 412.83 Tb159 418.21 390.94 30.56 31.27 467.13 479.22 11.5 14.15 18.73 20.63 28.69 16.44 21.48 25.58 29.52 14.8 11.01 447.59 433.23 Dy163 400.72 374.34 28.49 28.55 445.38 460.78 136.34 153.86 178.51 217.2 264.85 160.46 230.73 226.82 311.5 151.56 129.03 432.96 417.91 Ho165 425.78 396.02 30.7 31.66 471.84 486.02 51.71 54.72 56.43 76.49 84.01 54.83 79.42 67.85 103.84 52.16 49.49 455.12 440.01 Er166 401.4 373.01 29.32 29.98 448.52 460.65 238.96 239.3 233.86 337.57 357.67 238.35 327.12 268.57 449.87 230.61 233.21 431.32 417.38 Tm169 398.77 368.6 28.88 29.52 442.41 455.9 60.61 57.9 53.58 80.21 83.64 54.45 75.68 60.56 105.75 56.75 57.6 425.12 411.12 Yb172 435.93 401.69 31.72 32.93 482.76 497.96 691.68 652.96 551.49 864.18 893.29 567.82 803.45 648.27 1099 632.07 640.39 469.21 452.46 Lu175 410.55 381.15 29.38 30.33 461.87 474.22 104.62 89.86 85.42 132.49 138.21 97.46 109.79 89.77 169.07 96.08 102.11 439.46 423.91 Hf178 387.51 360.62 29.11 29.6 442.72 453.84 11394 10993 11051 12049 11804 12288 10346 10289 13475 10731 10068 425.15 407.11 Pb208 388.43 355.85 34.76 39.18 439.03 447.61 37.78 24.88 37.4 49.44 58.26 31.11 49.49 38.76 60.76 32.01 21.64 426.33 399.15 Th232 421.32 390.81 30.6 31.24 484.35 498.83 606.66 361.6 476.29 788.29 806.5 413.53 882.77 545.67 811.51 316.23 357.99 457.67 435.26 U238 427.74 394.22 33.91 37.5 497.15 512.02 1984 1180 1459 2152 2731 1334 1788 1117 2568 1186 1221 463.09 439.81
490 Table 7: Trace element data from the Najirah Granite (nr) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.7, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Details of this procedure are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures. The symbol ‘MC’ donates the discrete zircon morphological group (Chapter 3.2.1g).
Sample REE10 REE11 Nist610a Nist610b Nist612a Nist612b Nist610c Nist610d REE1 MC1 REE2 MC1 REE3 MC1 REE4 MC1 REE5 MC3 REE6 MC3 REE7 MC3 REE8 MC3 REE9 MC3 Nist610e Nist610f nr120 MC3 MC3 Na23 95051 94728 98946 100928 96052 94727 3.36 8.02 17.82 25.85 37.69 244.96 21.28 21.25 16.25 39.24 269.52 95007 95486 Mg24 465.12 464.94 60.32 60.68 467.11 457.31 2.51 0.15 6.77 5.93 178.56 4.67 813.02 1307.61 9.10 90.51 91.11 465.70 468.45 Al27 10047 10038 10222 9986 9945 9835 63.71 3.30 63.80 22.33 1165 173.38 1185 2125.63 277.00 986.54 1384 10016 10001 Si29 328329 328329 335917 335917 328329 328329 151965 151965 151965 151965 151965 151965 151965 151965 151965 151965 151965 328329 328329 P31 345.67 334.05 67.29 54.87 350.07 336.89 259.53 168.70 368.02 487.35 231.46 1195.71 449.40 418.15 792.50 665.47 643.06 342.06 346.83 K39 483.01 487.19 62.24 57.81 491.31 481.16 2.40 2.34 13.58 11.47 84.14 2.22 62.36 49.69 3.59 31.99 39.21 485.09 486.94 Ca43 82406 81736 84510 83604 81979 81382 108.99 77.22 474.50 805.56 828.82 475.39 286.24 791.46 1660 660.34 1888.24 82331 81964 Ti49 436.47 433.73 41.70 40.27 435.95 422.47 15.79 5.18 12.56 6.16 29.76 12.39 12.63 36.45 14.23 10.81 122.02 435.39 430.47 Fe57 214.70 609.70 449.05 574.65 585.65 555.62 24.74 355.37 314.51 327.60 496.30 290.87 1134.60 1570.17 253.35 391.26 436.21 456.97 442.23 Rb85 430.62 430.07 32.50 34.85 430.05 425.73 0.47 0.17 0.20 0.26 0.79 1.09 0.86 1.04 0.35 0.74 1.44 431.05 433.60 Sr88 498.30 499.87 76.02 73.01 494.65 483.78 1.22 0.19 1.00 0.75 7.16 5.20 2.79 6.53 4.16 2.52 30.24 504.63 499.41 Y89 454.22 452.79 35.50 34.51 445.33 437.91 2692 671.83 1125 1314 2192 6168 2272 3484 2260 2184 8833 449.10 451.99 Zr90 441.15 439.81 36.03 34.50 433.58 430.23 504155 485562 439002 417580 430151 485393 447663 468976 486107 467365 466083 442.63 438.06 Nb93 421.22 421.51 34.07 33.21 416.19 409.43 3.68 2.02 2.32 2.29 7.33 59.01 15.81 14.59 9.90 5.64 70.79 421.00 423.34 La139 459.27 458.77 36.58 35.61 453.54 447.47 1.21 0.01 3.14 4.84 9.93 19.85 7.83 8.82 19.90 3.73 56.70 461.40 460.27 Ce140 449.03 445.32 37.91 36.72 444.87 442.87 12.18 3.82 13.88 20.24 42.70 158.82 48.47 60.12 80.14 29.40 442.29 451.92 454.02 Pr141 431.55 429.45 35.54 35.25 426.05 421.97 1.20 0.04 1.57 2.60 4.84 16.36 4.40 6.16 10.07 2.35 49.33 433.35 435.23 Nd146 431.12 432.27 34.17 33.67 425.48 423.68 12.33 0.92 9.36 27.74 29.75 111.65 26.58 38.82 59.08 14.32 304.98 434.73 434.34 Sm147 451.62 452.10 36.43 35.79 443.56 441.78 19.78 2.29 8.16 12.48 25.64 81.44 18.76 34.94 30.74 13.97 195.87 454.23 452.41 Eu153 462.99 459.32 35.71 35.23 457.94 450.55 2.58 0.10 0.59 0.31 4.33 5.48 2.16 3.74 2.56 1.19 24.96 466.62 464.39 Gd157 422.89 418.84 33.82 33.35 415.62 408.35 86.86 13.66 28.78 37.94 81.40 204.42 66.50 118.67 78.44 52.64 405.38 424.42 422.81 Tb159 444.52 442.81 35.65 35.13 438.21 432.51 27.95 5.09 10.20 12.45 25.87 65.53 22.02 40.79 25.68 19.40 120.98 448.20 446.07 Dy163 430.06 424.55 32.76 32.74 421.64 416.51 296.71 63.86 115.45 141.81 266.87 703.00 247.67 427.29 267.73 223.08 1114 432.56 428.86 Ho165 451.37 448.65 35.85 35.48 445.01 439.71 99.39 24.12 40.81 49.74 82.71 239.57 85.12 130.98 82.15 79.61 312.96 454.11 451.49 Er166 429.10 425.95 34.07 33.60 421.34 415.06 389.23 105.80 171.58 203.93 309.41 965.36 346.87 489.50 324.66 341.05 1128.15 430.52 429.31 Tm169 423.34 419.78 33.66 33.16 414.95 410.68 76.54 22.95 36.25 43.73 62.70 191.32 72.95 95.87 65.08 73.26 213.50 423.74 422.79 Yb172 463.35 460.44 37.64 36.72 456.56 451.83 680.02 227.28 347.12 427.70 566.08 1708 678.02 847.97 580.67 689.12 1814 465.75 463.72 Lu175 436.99 434.92 34.20 33.66 429.01 424.63 108.64 37.60 55.08 61.05 83.16 261.46 98.80 122.84 87.28 114.08 258.74 438.74 436.85 Hf178 420.77 417.73 33.21 33.32 415.59 405.54 9515 10982 9593 9122 7423 13703 11019 11075 11279 12699 15751 422.69 415.37 Pb208 416.75 409.43 37.69 36.51 416.31 404.08 3.68 1.30 1.91 2.99 5.47 34.64 17.81 17.69 6.24 7.19 30.47 418.85 415.68 Th232 453.18 447.82 35.21 35.77 447.78 441.47 70.04 22.94 34.54 51.20 32.73 612.14 177.61 84.95 65.50 100.99 361.09 458.03 453.59 U238 458.95 453.45 37.66 37.34 455.28 451.51 198.30 98.79 123.21 167.78 238.97 2572 706.47 437.45 288.97 827.76 1580 464.88 460.48
491 Table 7 (continued): Trace element data from the Najirah Granite (nr) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.7, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Details of this procedure are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures. The symbol ‘MC’ donates the discrete zircon morphological group (Chapter 3.2.1g).
Sample REE12 REE13 REE14 REE15 REE16 REE17 REE18 REE19 REE20 REE21 REE22 REE23 REE24 Nist610g Nist610h Nist612c Nist612d Nist610i Nist610j Nist610k Nist610l nr120 MC2 MC2 MC2 MC2 MC2 MC2 MC2 MC2 MC3 MC3 MC2 MC2 MC2 Na23 95486 95323 95937 98314 95106 94929 36.76 6.79 11.46 52.07 21.76 13.27 7.22 30.10 384.11 11.51 18.16 21.78 5.34 95914 94432 Mg24 468.45 464.73 60.87 59.37 464.53 461.80 65.00 2.65 3.56 264.86 4.73 19.93 67.55 603.56 44.31 5.65 8.21 114.74 0.72 469.89 461.19 Al27 10001 9956 10223 9491 10030 10024 488.60 69.90 55.58 2232 78.04 134.94 409.12 1733 961.85 92.21 55.44 616.29 5.70 10022 9978 Si29 328329 328329 335917 335917 328329 328329 151965 151965 151965 151965 151965 151965 151965 151965 151965 151965 151965 151965 151965 328329 328329 P31 346.83 348.26 51.68 55.71 334.88 339.74 480.97 355.61 621.67 337.12 500.13 326.66 359.51 399.15 948.81 196.21 1348 344.33 306.71 340.41 346.81 K39 486.94 487.97 57.45 65.20 486.24 483.93 33.36 2.57 2.56 73.75 15.92 15.62 14.94 337.08 71.51 2.94 4.73 20.69 2.53 489.34 483.07 Ca43 81964 81348 83661 80453 81904 81396 1146 89.16 151.74 1320 262.90 505.80 300.47 897.39 2434 160.32 2804 400.15 231.19 82612 81085 Ti49 430.47 430.56 39.76 34.45 438.60 436.00 12.19 6.45 21.69 86.92 22.95 13.77 14.21 29.86 38.30 9.58 4.72 21.80 6.30 428.77 438.89 Fe57 442.23 476.34 352.38 308.60 440.26 478.03 333.06 276.13 374.66 1048.12 215.05 348.62 514.33 743.08 466.93 252.45 49.41 447.68 308.34 353.42 543.97 Rb85 433.60 428.27 31.76 31.84 431.95 429.71 0.99 0.27 0.49 1.25 0.53 0.11 0.54 3.20 1.00 0.21 0.48 0.51 0.17 434.71 427.26 Sr88 499.41 488.61 75.48 70.95 495.88 496.12 5.12 1.49 1.46 20.65 2.21 0.92 1.90 6.18 33.12 1.59 1.47 3.78 0.32 503.33 492.10 Y89 451.99 445.90 36.60 33.12 450.14 452.06 3628 1704 2729 6680 2426 817.43 2887 2880 5227 1110 3515 2233 958.19 451.36 447.70 Zr90 438.06 435.66 18.93 33.72 441.77 441.38 434680 481616 488300 454982 493816 470651 472822 478583 466164 445799 474672 467574 485309 436.03 443.91 Nb93 423.34 416.05 33.99 32.08 418.75 416.20 17.77 9.97 1.77 28.09 2.36 2.87 6.08 8.56 20.68 4.67 39.72 12.02 3.01 423.23 416.26 La139 460.27 451.59 36.62 34.21 456.43 455.52 7.61 1.06 1.93 24.10 2.46 5.04 2.86 7.76 22.25 1.34 52.83 4.20 0.86 460.30 455.26 Ce140 454.02 441.89 37.87 36.43 444.50 444.16 50.05 17.12 10.64 146.78 13.26 18.01 25.24 47.96 229.09 15.12 181.67 39.65 8.21 450.88 446.53 Pr141 435.23 424.93 35.71 33.65 427.22 425.90 5.86 0.82 1.26 16.49 1.66 2.01 1.96 5.26 16.68 0.90 28.86 3.18 0.56 434.44 426.59 Nd146 434.34 424.29 34.89 32.75 430.17 428.36 34.01 6.25 11.48 108.83 14.02 11.03 15.22 35.17 103.84 6.08 176.99 21.85 4.22 435.48 426.73 Sm147 452.41 443.31 36.96 33.78 451.51 449.49 34.29 8.80 16.11 102.85 16.99 7.40 19.71 33.00 81.44 7.62 68.34 22.14 4.77 453.47 447.62 Eu153 464.39 456.86 36.26 33.50 460.56 454.63 2.95 0.78 1.30 8.69 1.51 0.67 1.26 2.93 12.27 0.62 1.10 2.35 0.25 464.94 459.11 Gd157 422.81 414.47 34.71 31.55 419.29 416.41 112.46 39.62 71.44 305.20 68.30 23.56 83.29 106.45 212.42 30.98 128.80 74.77 22.80 423.89 416.88 Tb159 446.07 438.11 36.17 32.87 441.82 437.46 37.58 14.69 24.27 96.66 23.51 7.76 28.49 34.50 65.57 11.19 36.84 25.35 7.94 446.92 440.30 Dy163 428.86 422.34 33.15 30.67 426.15 420.31 419.61 171.93 274.10 891.13 256.82 87.08 315.22 350.54 625.71 124.72 391.77 260.01 94.53 429.34 425.54 Ho165 451.49 446.56 36.33 32.94 448.83 444.03 135.55 61.29 97.02 244.58 87.34 30.21 107.17 106.04 188.03 40.48 135.48 82.25 35.13 453.50 446.71 Er166 429.31 420.51 34.80 31.47 424.86 422.66 541.34 259.25 394.59 833.70 354.46 124.92 430.54 390.32 716.13 168.78 551.21 320.11 149.47 429.81 423.27 Tm169 422.79 415.81 34.43 31.13 419.81 416.55 109.08 53.60 78.63 153.74 70.92 26.76 85.99 76.57 146.11 35.81 113.15 63.58 32.43 423.59 417.53 Yb172 463.72 456.12 37.97 34.32 461.70 458.47 997.81 495.28 692.78 1259 633.46 259.79 765.01 679.19 1365 338.42 1037 562.14 318.29 463.10 460.90 Lu175 436.85 429.84 35.13 31.75 435.00 431.25 142.84 84.22 113.78 171.09 100.41 40.38 120.89 99.36 220.65 50.51 149.15 87.89 49.58 438.85 431.27 Hf178 415.37 413.29 35.55 30.90 421.01 415.28 11042 12949 9404 9907 9728 9278 10348 9986 12151 10335 11910 10950 9954 420.66 414.66 Pb208 415.68 406.89 37.10 36.67 412.61 409.95 13.11 6.27 5.29 29.61 4.70 1.58 9.43 7.73 24.06 3.08 20.70 8.39 2.03 422.41 404.70 Th232 453.59 446.21 36.71 32.55 449.33 443.26 162.62 116.17 94.39 73.06 74.85 24.38 136.86 51.64 91.93 37.83 400.04 85.52 43.89 451.87 452.12 U238 460.48 454.54 36.91 36.09 451.90 450.42 696.76 477.21 260.33 795.76 234.17 109.13 405.12 304.51 1226 200.71 1486 396.20 158.64 468.03 448.44
492 Table 8: Trace element data from the Wadbah Suite (wb) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.8, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Details of this procedure are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures. The symbol ‘MC’ donates the discrete zircon morphological group (Chapter 3.2.1h).
Sample Nist610a Nist610b Nist612a Nist612b Nist610c Nist610d REE1 MC1 REE2 MC1 REE3 MC1 REE4 MC1 REE5 MC3 REE6 MC3 REE7 MC3 REE8 MC3 Nist610e Nist610f wb65 Na23 96242 96040 97255 95830 95333 95753 16.29 31.72 15.75 15.37 14.86 14.77 16.18 15.90 95215 95019 Mg24 463.62 469.16 61.51 57.52 463.34 463.90 4.09 0.46 0.92 6.99 1.95 3.04 205.11 0.57 469.68 459.99 Al27 10060 9992 9606 9352 9861 9883 9.16 4.88 3.62 28.23 21.46 30.02 375.26 3.08 10047 9963 Si29 328329 328329 335917 335917 328329 328329 151965 151965 151965 151965 151965 151965 151965 151965 328329 328329 P31 313.08 354.83 20.91 57.55 369.77 377.90 158.88 162.92 167.33 569.81 158.93 161.86 184.15 157.76 365.51 344.82 K39 471.39 473.01 56.47 58.61 484.47 501.52 6.97 32.11 5.76 5.55 17.23 7.30 12.26 4.16 487.68 492.06 Ca43 81875 81313 81650 78093 82820 83248 180.44 187.20 150.92 1046.26 143.86 151.97 196.02 172.41 82188 82454 Ti49 415.43 434.67 37.55 38.57 440.84 462.18 8.79 20.03 4.21 11.74 7.15 27.61 4.52 7.18 441.63 434.87 Fe57 415.23 435.92 189.15 126.15 517.54 460.23 95.37 64.77 81.95 260.49 68.01 81.22 2546.07 88.06 491.45 438.10 Rb85 406.37 410.32 32.31 32.55 452.50 454.58 0.10 0.14 0.12 0.11 0.08 0.17 0.34 0.03 436.29 435.97 Sr88 471.75 468.95 70.91 71.33 524.52 526.22 0.18 0.19 0.16 0.56 0.05 0.92 0.84 0.05 505.22 502.52 Y89 424.42 427.87 34.71 32.93 472.30 478.03 1363 1454 1048 859.33 1305 1485 1324 1512 456.43 452.98 Zr90 414.55 420.56 34.36 34.39 458.94 468.04 510032 564263 502492 501795 559091 514734 491337 510188 454.98 438.11 Nb93 396.16 400.67 32.26 32.92 441.92 445.26 2.78 1.93 5.29 5.09 4.46 3.76 7.17 2.98 425.95 423.11 La139 424.60 427.17 35.02 35.04 486.75 489.09 0.24 0.35 0.17 24.10 0.14 1.42 1.04 0.08 465.71 462.38 Ce140 417.19 416.46 36.89 37.63 474.81 476.95 17.33 9.97 16.91 79.17 20.41 22.91 30.08 16.99 455.49 452.26 Pr141 396.47 398.46 34.52 34.34 456.44 460.14 0.44 0.69 0.36 10.52 0.41 1.83 1.67 0.31 438.82 433.52 Nd146 396.34 396.26 32.78 33.00 457.43 460.17 8.28 10.81 4.49 59.88 7.18 18.14 17.61 7.10 437.60 435.56 Sm147 414.28 413.98 34.37 34.68 475.86 482.59 14.04 18.83 7.62 22.35 13.02 20.88 16.21 15.03 458.80 453.17 Eu153 424.80 423.93 34.32 34.49 489.46 493.90 1.16 2.64 0.94 2.27 0.72 2.62 11.45 0.80 470.94 465.68 Gd157 384.46 383.61 32.20 31.79 445.98 453.38 57.20 68.89 33.65 43.43 51.62 65.09 50.83 63.02 427.77 421.52 Tb159 406.67 407.23 33.83 33.59 470.90 476.18 16.41 19.62 10.90 11.19 15.30 18.44 15.16 18.05 451.42 445.65 Dy163 389.94 390.61 31.02 31.01 452.39 458.22 166.69 189.13 118.63 107.74 156.60 180.12 156.35 182.22 435.63 431.02 Ho165 411.83 411.81 33.87 33.62 479.14 485.41 53.27 58.45 39.46 33.81 51.03 57.34 50.61 58.16 458.18 454.06 Er166 389.17 388.35 31.78 31.96 452.01 461.06 201.49 213.13 155.90 129.62 194.55 216.17 197.34 218.39 432.70 431.45 Tm169 385.96 383.37 31.30 31.81 447.07 452.92 40.20 43.49 33.06 27.04 39.40 44.48 41.25 43.66 428.38 425.51 Yb172 420.48 418.21 34.77 34.97 489.85 497.53 372.57 402.21 316.99 260.48 364.98 417.78 387.72 396.62 470.28 467.08 Lu175 396.31 397.16 32.38 32.63 465.08 471.78 55.75 58.18 45.15 38.11 54.79 60.79 55.84 58.22 442.98 438.92 Hf178 376.84 379.19 31.91 30.34 445.33 451.43 8831 8644 9733 9044 10052 11051 9694 8999 427.33 420.85 Pb208 370.31 376.39 37.36 37.91 436.87 443.64 2.43 1.80 2.66 2.38 3.27 3.77 9.91 2.49 420.52 418.40 Th232 405.42 408.68 33.58 33.84 486.15 493.34 43.60 33.63 43.55 38.29 56.95 63.00 59.33 50.04 460.35 453.54 U238 412.13 414.03 36.81 37.76 491.91 502.31 142.52 112.06 212.04 177.01 194.82 293.66 306.49 156.37 467.98 460.22
493 Table 8 (continued): Trace element data from the Wadbah Suite (wb) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.8, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Details of this procedure are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures. The symbol ‘MC’ donates the discrete zircon morphological group (Chapter 3.2.1h).
Sample REE10 REE11 REE12 REE13 REE14 REE15 REE16 Nist610g Nist610h Nist612c Nist612d Nist610i Nist610j REE9 MC2 Nist610k Nist610l wb65 MC2 MC2 MC2 MC2 MC2 MC2 MC2 Na23 95019 94685 94027 95104 96238 94891 36.50 17.06 15.67 16.66 30.04 21.06 23.93 13.44 95268 94971 Mg24 459.99 463.46 59.04 58.18 470.72 462.59 32.85 1.49 0.60 1.03 11.04 1.02 42.89 0.74 468.43 462.27 Al27 9963 9998 9270 9188 10061 9950 493.05 3.35 39.08 15.79 44.51 2.74 423.28 4.96 10055 9967 Si29 328329 328329 335917 335917 328329 328329 151965 151965 151965 151965 151965 151965 151965 151965 328329 328329 P31 344.82 309.21 56.37 54.25 356.36 335.27 638.42 218.54 112.64 950.08 1538.56 844.03 191.19 173.85 345.19 342.36 K39 492.06 487.61 61.57 66.48 483.57 476.62 160.61 6.11 38.13 13.09 26.56 3.89 64.60 3.97 484.24 491.68 Ca43 82454 81046 75981 76341 82318 80917 1722.04 156.63 178.46 2299 4391.36 2382.78 532.36 156.09 82282 81654 Ti49 434.87 437.19 32.86 30.63 429.87 422.01 17.20 8.63 5.75 8.58 10.32 9.75 70.63 10.21 439.35 434.32 Fe57 438.10 510.97 110.92 141.79 388.76 431.17 4081.37 92.71 69.68 88.08 284.05 61.47 878.71 63.14 419.98 521.15 Rb85 435.97 432.11 32.99 32.46 426.41 420.96 1.75 0.04 0.20 0.11 0.22 0.08 0.68 0.14 433.01 434.34 Sr88 502.52 494.07 68.90 69.07 493.85 487.41 1.25 0.05 0.04 0.25 1.11 0.39 4.49 0.07 500.39 499.71 Y89 452.98 451.91 32.20 30.19 445.16 438.64 1076 1035 1108 1671 974.62 843.05 2381 1815 458.17 447.83 Zr90 438.11 440.57 31.83 29.15 433.26 426.10 545525 514678 504093 501616 506524 538273 502888 541645 475.41 415.56 Nb93 423.11 420.84 31.67 30.93 414.95 408.03 2.62 3.62 2.43 2.01 2.94 1.90 15.23 2.64 423.62 420.93 La139 462.38 455.77 33.37 32.38 452.79 445.79 3.88 0.40 0.06 21.82 28.21 7.36 38.31 0.05 463.80 457.48 Ce140 452.26 447.44 35.85 35.51 443.79 435.56 14.18 17.61 12.44 62.56 87.65 25.79 130.63 17.57 453.06 448.88 Pr141 433.52 429.38 32.70 32.40 424.47 418.26 2.01 0.41 0.21 8.45 13.89 3.61 19.66 0.51 435.67 430.56 Nd146 435.56 432.07 31.25 31.27 426.58 417.47 16.57 5.65 4.11 52.99 88.61 23.63 122.21 10.71 437.22 430.99 Sm147 453.17 451.35 33.25 32.02 444.78 439.88 14.72 9.86 8.67 28.27 31.95 13.42 78.58 20.46 457.40 449.81 Eu153 465.68 459.93 32.49 31.65 456.55 447.35 3.58 0.75 0.66 2.44 4.46 1.96 58.32 1.33 468.07 461.51 Gd157 421.52 418.89 29.55 29.18 417.52 409.98 48.79 40.00 42.29 81.72 57.19 37.14 147.41 79.15 426.84 418.12 Tb159 445.65 441.30 32.06 30.80 439.30 432.12 13.52 11.88 12.60 21.79 13.46 10.37 41.52 22.53 450.30 441.33 Dy163 431.02 424.09 29.71 28.55 422.72 414.33 131.46 123.12 132.69 210.38 121.36 102.80 377.24 223.98 435.40 424.42 Ho165 454.06 448.43 32.19 30.81 444.97 436.40 41.28 39.77 43.16 64.56 37.20 32.99 99.73 70.91 459.46 446.81 Er166 431.45 424.48 30.09 29.36 422.45 414.51 156.53 152.69 163.66 236.11 141.04 124.79 350.78 266.88 435.00 423.36 Tm169 425.51 418.34 29.90 29.09 416.62 406.92 32.06 30.99 33.93 46.89 27.98 26.22 70.41 52.09 429.59 417.85 Yb172 467.08 458.86 33.42 32.37 457.09 449.27 305.98 288.79 324.26 429.57 261.20 246.49 663.96 467.08 470.80 459.24 Lu175 438.92 434.06 30.49 29.68 430.51 422.23 49.81 43.56 45.02 62.37 43.20 36.36 92.10 70.73 445.29 431.39 Hf178 420.85 414.44 29.68 29.11 416.15 405.08 7556 8966 8704 7682 8516 8346 9194 9816 429.50 412.70 Pb208 418.40 411.40 36.84 38.07 412.53 399.23 2.05 2.97 1.90 2.42 8.61 1.57 131.24 2.94 420.75 412.17 Th232 453.54 449.56 31.46 30.79 447.15 437.45 17.35 38.88 33.77 43.83 32.88 17.55 128.32 58.54 461.15 447.35 U238 460.22 455.38 35.79 37.38 452.98 443.92 75.15 139.21 137.95 131.15 105.99 67.03 511.17 190.41 465.51 456.05
494 Table 9: Trace element data from the Ibn Hashbal Suite (ih) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.9, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Details of this procedure are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures.
Sample Nist610a Nist610b Nist612a Nist612b Nist610c Nist610d REE1 REE2 REE3 REE4 REE5 REE6 REE7 Nist610e Nist610f ih68 Na23 95965 96683 97395 94854 94678 94693 12.68 17.55 19.78 67.07 16.54 17.17 14.47 95520 94826 Mg24 471.11 464.26 55.52 55.81 455.00 456.06 2.89 37.72 1.01 0.48 4.97 175.57 92.60 460.63 467.16 Al27 10109 9947 9128 9313 9894 9883 10.76 207.71 7.89 188.26 75.83 540.25 226.65 10063 9994 Si29 328329 328329 335917 335917 328329 328329 151965 151965 151965 151965 151965 151965 151965 328329 328329 P31 309.55 344.21 43.74 55.83 367.29 381.24 269.84 1087 1029 119.20 111.23 325.69 320.56 329.27 335.76 K39 483.23 473.72 64.39 53.60 489.40 482.95 3.96 39.45 5.99 147.41 6.13 38.07 12.17 496.28 490.03 Ca43 80654 79541 79699 81204 83324 84903 168.16 2371 2223 193.43 196.73 416.16 148.91 82243 81903 Ti49 432.46 425.84 33.72 26.77 442.90 452.99 8.77 20.18 5.94 12.46 19.54 121.45 6.72 438.00 437.65 Fe57 443.95 442.53 135.80 82.65 416.15 432.42 58.86 1483 67.58 65.40 157.58 2290 2731 458.53 487.19 Rb85 403.14 405.52 32.49 32.86 453.71 457.55 0.25 0.43 0.05 0.53 0.06 0.16 0.57 435.16 431.55 Sr88 470.01 462.74 67.65 74.49 528.65 528.49 0.30 3.72 0.61 0.09 1.56 3.78 1.57 502.44 497.78 Y89 425.81 418.19 30.27 33.01 481.49 485.23 3374 2617 856 980 1223 858.96 8261 457.43 447.95 Zr90 413.72 408.96 30.68 32.84 468.08 475.50 537118 541679 566098 538279 540027 518894 511318 450.96 432.55 Nb93 396.30 390.06 30.80 32.91 446.88 449.89 15.21 20.08 3.68 4.77 4.10 6.44 34.37 421.89 418.73 La139 426.39 414.60 31.37 34.26 490.79 495.59 1.77 50.41 52.86 0.77 6.88 56.32 9.10 465.34 453.85 Ce140 416.86 406.28 35.13 37.84 477.21 482.49 81.41 216.29 152.23 27.96 52.98 112.02 155.92 452.88 444.67 Pr141 399.74 386.31 31.88 34.98 459.11 462.29 1.84 31.06 18.52 0.52 7.13 22.38 7.71 435.31 425.39 Nd146 395.27 384.25 29.26 33.23 458.75 466.54 20.37 202.50 100.01 6.76 56.69 139.15 66.74 436.97 426.66 Sm147 415.09 400.51 31.17 34.07 483.53 487.09 33.75 101.70 25.50 10.26 41.85 64.23 81.60 455.10 445.44 Eu153 423.47 414.51 31.33 34.57 493.60 498.56 0.96 6.95 0.56 0.33 3.31 5.03 3.40 465.80 456.93 Gd157 383.81 377.01 27.75 31.44 451.82 453.38 148.36 173.35 43.31 39.35 81.08 88.63 323.56 427.51 414.42 Tb159 406.67 397.57 29.41 33.67 477.52 482.11 44.79 42.03 11.03 11.72 19.73 17.38 106.96 450.74 437.10 Dy163 389.27 379.38 26.82 30.51 459.32 463.85 438.77 363.29 108.92 120.15 169.95 124.65 1114 435.63 421.34 Ho165 411.85 400.89 29.36 33.14 484.81 490.43 134.75 103.09 34.52 38.85 48.65 31.79 349.28 457.64 444.80 Er166 389.63 377.78 27.66 31.68 458.48 466.84 489.62 359.97 132.47 146.52 173.94 110.12 1268 433.14 421.34 Tm169 384.11 373.50 28.02 31.40 453.52 460.96 90.20 63.20 26.07 28.74 32.44 20.03 225.55 425.66 416.27 Yb172 420.55 406.00 30.61 34.73 496.13 503.02 745.62 507.48 232.85 254.75 281.93 172.58 1770 468.28 457.09 Lu175 396.92 386.03 28.25 32.27 472.52 477.27 113.79 76.44 37.01 38.64 43.81 27.87 245.92 442.83 429.44 Hf178 376.57 366.40 27.93 31.84 454.14 461.66 7572 8766 8591 7792 7890 7363 7106 425.05 412.18 Pb208 369.92 363.70 37.37 38.10 445.56 447.73 13.06 18.90 2.12 3.81 2.49 6.04 19.47 418.11 406.00 Th232 405.13 394.97 29.83 34.08 497.51 497.72 254.95 184.47 38.11 72.06 36.71 19.35 344.26 459.13 442.53 U238 406.50 405.52 36.48 37.95 503.60 501.35 582.35 620.27 149.38 195.12 227.57 253.57 1367 460.93 449.82
495 Table 9 (continued): Trace element data from the Ibn Hashbal Suite (ih) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.9, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Details of this procedure are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures.
Sample Nist610g Nist610h Nist612c Nist612d Nist610i Nist610j REE8 REE9 REE10 REE11 REE12 REE13 REE14 REE15 Nist610k Nist610l ih68 Na23 94826 95830 94862 95779 94358 95423 25.99 37.23 15.36 16.35 16.71 17.62 22.85 18.99 95401 95145 Mg24 467.16 466.30 58.44 58.54 472.87 459.70 56.80 1.17 10.10 3.54 42.26 3.40 11.20 0.70 462.94 466.60 Al27 9994 9923 9294 9322 9989 10048 478.75 19.37 102.01 55.60 176.37 39.51 85.39 3.63 10134 9901 Si29 328329 328329 335917 335917 328329 328329 151965 151965 151965 151965 151965 151965 151965 151965 328329 328329 P31 335.76 345.58 54.89 73.25 362.42 344.48 499.91 449.24 158.68 259.28 255.88 120.61 171.76 126.08 343.97 335.24 K39 490.03 478.32 65.74 66.36 480.50 480.50 29.74 4.25 4.07 4.17 52.22 4.51 9.52 4.80 495.24 482.08 Ca43 81903 79934 77424 80705 83237 81828 945.10 181.65 190.60 182.46 488.64 193.59 211.38 243.02 81461 81924 Ti49 437.65 423.70 35.86 30.61 422.42 451.58 35.32 4.11 17.04 11.59 13.90 5.36 15.61 7.13 436.41 431.23 Fe57 487.19 497.71 114.41 105.27 426.02 393.00 3529.90 63.21 571.20 62.16 259.82 67.16 609.50 144.36 373.38 551.77 Rb85 431.55 428.81 31.26 33.30 427.53 431.42 0.80 0.34 0.08 0.30 0.24 0.04 0.25 0.05 430.71 432.69 Sr88 497.78 490.75 71.71 69.43 495.55 499.83 16.87 1.39 1.31 1.26 1.04 0.66 1.13 0.02 497.69 497.66 Y89 447.95 441.12 32.76 31.23 449.86 452.31 9069 7375 1613 5778 861.99 1117 2160 627.75 452.80 447.78 Zr90 432.55 434.39 33.14 32.55 436.84 444.85 489401 513048 533714 529457 515616 512498 505998 512354 442.76 438.03 Nb93 418.73 416.56 31.43 31.65 419.04 420.51 109.09 113.87 8.78 24.68 3.73 5.99 13.79 2.40 419.44 419.47 La139 453.85 449.43 34.05 33.75 457.82 460.10 707.10 4.18 5.30 7.30 16.14 2.62 8.49 0.03 458.58 456.49 Ce140 444.67 443.32 37.48 37.11 448.17 449.90 1345 262.09 58.85 129.02 64.21 35.03 123.89 18.45 445.96 449.28 Pr141 425.39 426.04 34.51 33.42 430.05 432.28 163.98 4.64 6.11 5.90 8.53 3.02 7.21 0.14 429.97 429.46 Nd146 426.66 425.99 32.89 32.17 430.49 433.71 862.05 42.45 46.97 53.39 57.47 23.94 53.81 3.27 432.35 429.43 Sm147 445.44 445.85 34.09 32.88 452.01 454.96 324.95 61.71 34.38 71.47 31.73 20.45 40.84 6.33 451.19 448.86 Eu153 456.93 457.72 34.15 33.35 461.37 463.80 28.45 2.81 2.53 2.89 2.47 1.30 2.56 0.25 462.62 459.48 Gd157 414.42 414.12 31.37 30.73 420.25 422.77 552.32 281.47 78.50 271.01 55.64 51.30 104.58 25.61 425.52 415.20 Tb159 437.10 434.73 32.64 31.92 444.13 447.62 137.61 93.54 21.20 80.17 13.17 14.33 30.46 7.38 449.28 436.85 Dy163 421.34 415.83 30.79 29.47 429.01 430.64 1242 946.18 198.61 764.02 113.61 138.77 288.37 74.19 432.62 420.90 Ho165 444.80 438.94 33.03 31.87 452.55 453.01 353.42 286.01 60.27 226.91 33.21 42.91 86.38 23.71 456.41 443.04 Er166 421.34 417.42 31.15 30.18 427.89 430.26 1225 1012 223.42 806.61 120.60 160.05 309.58 92.48 433.88 418.95 Tm169 416.27 411.93 30.70 29.98 422.70 424.23 213.90 177.62 43.06 146.75 23.32 31.06 58.56 18.59 428.13 412.72 Yb172 457.09 453.60 34.55 33.44 462.87 465.41 1663 1377 366.77 1196 211.10 272.88 498.55 171.30 470.83 453.47 Lu175 429.44 424.95 31.21 30.56 437.51 438.92 232.22 189.14 55.91 171.47 32.59 40.00 68.86 27.51 443.11 427.18 Hf178 412.18 406.23 30.82 30.84 423.40 421.90 6958 7244 7523 7257 7041 7359 7241 7218 427.47 408.44 Pb208 406.00 409.61 37.59 40.19 417.33 416.42 45.12 51.43 5.41 21.84 1.83 2.36 8.59 1.30 415.01 410.46 Th232 442.53 442.86 32.57 32.41 454.58 454.19 808.22 1038 83.80 435.63 29.53 43.37 152.33 24.01 458.52 443.18 U238 449.82 450.72 37.13 37.83 463.42 462.66 2042 2502 421.91 980.71 162.23 215.25 634.48 89.85 461.30 451.11
496 Table 10: Trace element data from the Ar Ruwaydah Suite (ku) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.10, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Details of this procedure are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures.
Sample Nist610a Nist610b Nist612a Nist612b Nist610c Nist610d REE1 REE2 REE3 REE4 REE5 REE6 REE7 REE8 REE9 Nist610e Nist610f ku139 Na23 92866 95002 96169 97861 92611 93476 20.81 830.90 2289 2091 43.19 3295 2487 972.50 1704 97090 95158 Mg24 447.04 453.05 51.12 55.83 440.61 441.24 291.41 1.86 82.55 70.71 350.15 23.59 58.78 325.11 17.07 476.58 474.77 Al27 9902 9922 8806 9097 9584 9674 708.51 62.15 1690 548.58 546.51 510.21 964.84 3074 1726 10205 10101 Si29 328329 328329 335917 335917 328329 328329 151965 151965 151965 151965 151965 151965 151965 151965 151965 328329 328329 P31 345.38 348.58 51.04 35.43 404.01 394.48 1546 1071 877.09 791.98 558.32 539.83 661.83 1504 2801 314.80 338.17 K39 475.56 465.83 53.74 64.14 459.76 476.34 29.45 17.65 997.98 151.03 40.76 758.74 870.03 256.35 181.13 491.10 496.89 Ca43 82191 81935 77578 79840 78374 79339 2694 1440 20503 4845 453.51 23514 16341 17964 20847 84436 81660 Ti49 440.44 412.73 31.79 41.94 420.16 430.00 11.92 11.93 19.70 28.19 38.93 222.40 32.55 197.10 11.53 453.25 426.96 Fe57 511.23 416.48 107.05 128.24 406.50 454.79 1112 48.64 3748 1709 871.30 4328 3390 3525 250.88 453.19 478.12 Rb85 513.05 399.55 32.81 34.28 415.94 409.94 0.10 0.24 3.73 0.51 0.19 0.70 2.18 0.72 1.34 438.36 439.37 Sr88 597.48 469.30 67.65 70.16 475.25 470.44 7.35 9.55 201.19 79.84 2.44 325.78 286.29 240.14 109.45 516.84 500.07 Y89 534.10 426.12 30.10 30.92 431.35 428.98 1028 3991 3086 2077 1715 4414 2102 3206 2781 465.92 451.60 Zr90 484.53 402.18 29.75 31.71 434.12 454.86 481370 566659 504277 595353 626742 543628 594328 619419 628848 566.20 345.13 Nb93 500.60 395.88 30.84 31.14 400.21 402.60 2.58 13.81 12.84 5.84 3.41 25.46 9.84 18.13 6.80 426.45 426.36 La139 608.95 428.23 31.79 33.74 435.91 432.42 42.77 5.07 82.43 198.96 14.51 32.98 222.22 775.95 50.05 467.55 465.90 Ce140 601.95 417.20 36.27 37.39 428.47 421.95 275.13 43.47 182.48 821.27 107.07 98.97 383.22 4261.19 147.81 462.54 452.89 Pr141 586.96 398.27 32.05 33.53 407.73 403.35 37.58 1.75 30.77 103.26 11.87 5.72 43.26 588.21 20.61 442.69 437.48 Nd146 589.74 395.07 29.91 31.65 407.20 397.21 289.41 18.05 153.25 595.20 78.49 25.42 207.84 4035.05 112.12 448.44 438.58 Sm147 615.24 410.97 30.70 31.56 425.14 416.08 136.39 33.75 56.50 186.70 38.39 19.42 46.82 1518 60.37 472.51 456.21 Eu153 641.80 426.19 31.66 32.95 434.97 427.66 4.80 3.37 2.56 17.61 2.38 4.04 4.58 86.09 4.47 481.70 467.33 Gd157 565.52 385.70 28.37 30.29 392.27 389.38 126.15 152.07 92.73 158.77 61.29 105.65 74.22 1137 127.90 434.51 429.85 Tb159 611.69 408.33 29.98 31.14 417.82 415.71 15.58 44.50 26.28 24.09 15.35 38.05 20.34 102.07 33.44 461.51 447.66 Dy163 587.99 389.97 27.85 28.82 402.02 397.25 108.64 438.68 292.63 212.23 169.11 434.53 219.35 442.27 321.22 444.01 433.17 Ho165 632.46 411.33 30.09 31.68 429.53 417.64 33.19 139.12 105.82 70.65 62.79 152.80 75.67 92.20 101.63 467.56 455.52 Er166 599.66 386.77 28.53 29.56 407.59 394.14 138.00 536.34 465.49 299.18 272.02 636.07 314.27 328.00 399.53 444.17 431.98 Tm169 596.70 386.75 28.02 29.16 402.42 385.68 31.72 108.09 106.39 67.88 61.43 138.00 70.41 75.25 87.32 438.31 426.31 Yb172 664.91 423.15 31.53 32.38 440.10 416.44 338.20 994.22 1093 700.09 632.97 1382 732.62 852.24 903.56 485.50 469.12 Lu175 630.76 398.98 28.69 30.01 416.70 398.71 51.05 154.10 175.58 107.40 98.05 194.40 104.76 140.54 121.55 457.19 439.01 Hf178 591.67 381.92 27.09 28.76 395.42 377.97 8886 10414 11564 12606 9310 9264 11556 11572 9362 440.47 425.01 Pb208 626.06 379.66 38.61 38.73 382.04 376.02 12.84 153.36 58.61 26.62 7.36 158.95 848.25 52.30 169.01 434.41 422.66 Th232 669.90 413.80 29.59 31.18 427.05 414.74 190.62 3299 1041 390.97 47.89 4106 1056 2036 1194 472.39 456.40 U238 696.52 416.91 36.87 36.49 432.81 420.56 563.61 8965 6993 3426 207.83 11458 6361 4311 5986 482.40 461.74
497 Table 10 (continued): Trace element data from the Ar Ruwaydah Suite (ku) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.10, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Details of this procedure are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures.
Sample Nist610g Nist610h Nist612c Nist612d Nist610i Nist610j REE10 REE11 REE12 REE13 REE14 REE15 Nist610k Nist610l ku139 Na23 95158 94853 96235 98560 94475 95730 1059 39.75 135.51 1743 2290 670.89 95887 94689 Mg24 474.77 472.36 51.93 53.89 457.96 467.30 10.76 0.47 6.21 14.26 81.82 64.24 473.18 459.33 Al27 10101 9994 9228 9404 9853 10030 229.62 4.91 46.53 186.55 1280 198 9937 10103 Si29 328329 328329 335917 335917 328329 328329 151965 151965 151965 151965 151965 151965 328329 328329 P31 338.17 318.36 37.87 38.40 374.02 324.29 558.95 679.28 681.15 832.77 593.69 1053.94 303.99 373.68 K39 496.89 489.09 62.47 60.47 485.44 484.07 117.87 5.17 94.52 235.36 317.95 28.61 484.43 488.00 Ca43 81660 81257 77849 79184 79796 83162 1708 165.51 248.14 5009 7570 472.19 81768 82130 Ti49 426.96 443.29 40.84 43.91 432.46 424.97 8.15 5.20 7.96 8.49 61.05 8.33 425.55 444.45 Fe57 478.12 464.45 131.01 114.10 465.60 476.82 221.80 31.43 69.99 1684 1898 565.98 428.86 472.45 Rb85 439.37 439.50 32.26 33.02 432.16 432.22 0.08 0.11 0.33 0.19 0.68 0.22 433.99 427.40 Sr88 500.07 501.23 69.29 69.18 496.10 496.71 31.64 0.26 1.20 87.61 134.15 10.92 498.33 497.42 Y89 451.60 455.24 31.21 32.49 441.90 449.09 1728 2003 2045 1979 3378 1959 450.09 452.14 Zr90 345.13 416.66 5.36 3.97 496.44 491.31 532941 478372 603429 535446 595694 555322 384.72 386.68 Nb93 426.36 423.64 31.99 32.02 420.23 419.06 5.67 5.03 6.02 5.69 13.66 2.86 420.15 418.38 La139 465.90 460.99 32.57 33.35 456.50 457.48 103.77 0.41 1.96 100.98 252.95 65.27 456.88 457.90 Ce140 452.89 451.19 35.68 37.05 448.62 449.83 104.13 10.34 11.98 315.30 884.38 258.34 448.26 446.65 Pr141 437.48 435.34 32.95 33.41 427.44 430.33 15.07 0.16 0.72 37.93 134.57 36.44 428.93 430.80 Nd146 438.58 438.73 31.08 31.91 426.04 431.64 46.94 3.23 4.97 194.79 1035.19 205.88 429.04 433.07 Sm147 456.21 458.84 32.04 32.86 442.07 451.44 10.52 10.42 8.20 49.26 550.56 57.09 448.88 453.77 Eu153 467.33 470.78 32.62 32.94 456.68 460.86 0.74 1.09 0.71 9.13 31.33 3.59 459.47 463.52 Gd157 429.85 432.05 29.61 29.57 414.13 421.04 48.86 60.63 48.72 61.57 533.66 64.52 417.59 422.31 Tb159 447.66 451.26 30.88 31.64 440.72 439.54 16.49 20.03 17.67 17.78 68.85 16.78 443.06 444.03 Dy163 433.17 430.89 28.68 29.04 427.34 424.31 182.74 212.74 200.96 201.47 428.41 188.76 427.15 426.53 Ho165 455.52 455.02 31.27 31.64 444.14 451.35 62.64 71.31 71.99 70.45 116.38 68.14 451.15 448.65 Er166 431.98 431.18 28.79 29.67 420.10 430.45 262.29 288.80 309.54 300.69 471.59 295.36 427.58 424.82 Tm169 426.31 425.59 29.09 29.47 413.04 423.19 59.40 64.14 67.38 68.51 108.07 69.70 419.26 421.76 Yb172 469.12 469.02 32.15 33.36 457.31 465.15 625.23 666.22 656.53 712.97 1124 752.69 461.25 461.64 Lu175 439.01 438.76 29.72 30.27 424.23 435.17 89.40 94.10 110.24 107.13 187.56 112.72 434.26 438.12 Hf178 425.01 420.46 27.86 27.89 412.86 416.60 11495 8904 13940 12305 14299 12263 417.94 419.53 Pb208 422.66 417.30 37.59 39.28 410.75 412.00 62.10 45.55 29.36 24.22 60.28 18.57 414.83 413.14 Th232 456.40 455.53 30.82 31.43 443.36 448.69 571.92 750.85 516.39 425.67 1386 159 454.98 449.60 U238 461.74 458.31 35.64 38.35 454.49 457.35 3762 4371 3392 4741 3844 2770 463.19 453.22
498 Table 11: Trace element data from the Haml Suite (hla) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.11, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Details of this procedure are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures.
Sample Nist610a Nist610b Nist612a Nist612b Nist610c Nist610d REE1 REE2 REE3 REE4 REE5 REE6 REE7 REE8 REE9 REE10 REE11 Nist610e Nist610f hla110 Na23 92817 94490 102923 100335 97848 98493 156.43 26.60 14.58 32.22 17.21 20.62 22.14 21.58 29.30 37.62 103.35 95093 93222 Mg24 454.83 459.46 56.79 62.03 477.66 474.45 15.17 56.61 1.59 15.02 431.11 66.06 282.27 2.09 5.71 1.86 59.02 467.51 456.11 Al27 9851 9879 9414 9463 10112 10192 338.87 257.08 2.87 41.56 591.66 459.35 454.79 10.73 33.02 6.81 160.72 10044 9879 Si29 328329 328329 335917 335917 328329 328329 151965 151965 151965 151965 151965 151965 151965 151965 151965 151965 151965 328329 328329 P31 356.75 376.52 40.75 62.78 338.07 348.51 1985 370.18 224.26 4061 2955 1750 329.82 153.63 238.36 1653 310.16 357.28 325.42 K39 484.54 483.91 70.35 66.42 488.18 491.80 208.70 30.11 4.48 9.60 56.15 37.33 35.06 5.48 15.05 5.02 17.24 485.66 483.74 Ca43 82797 81222 82246 75852 82221 81265 5184 776.06 168.42 11293 8976 4586 378.01 204.16 194.45 4313 959.08 82353 81457 Ti49 440.91 429.36 35.46 28.39 435.55 420.39 11.17 46.73 6.75 5.63 8.42 62.75 30.26 15.92 25.76 10.14 19.19 441.31 432.51 Fe57 491.64 476.92 109.02 132.15 413.32 452.13 87.61 632.57 40.81 120.54 1770 198.31 1108 59.75 58.00 78.91 252.66 438.82 491.40 Rb85 477.89 444.82 32.28 29.01 393.58 392.83 0.66 0.54 0.09 0.08 0.50 0.32 0.32 0.06 0.05 0.04 0.36 447.77 449.34 Sr88 559.48 513.73 66.96 63.33 451.61 451.68 3.54 3.33 0.07 5.17 3.73 10.97 1.84 0.09 0.30 4.73 2.69 517.76 520.11 Y89 508.90 462.83 30.24 28.89 409.42 408.80 916.64 677.60 639.80 557.38 1076 817.96 1049 335.19 497.31 789.72 1714 470.40 467.44 Zr90 471.18 441.66 29.20 29.37 414.98 423.77 500280 587376 582431 656904 659817 503878 495135 483382 471306 473220 479071 673.56 375.80 Nb93 475.52 432.11 29.74 29.01 379.96 380.07 1.60 3.79 1.10 1.18 1.71 9.50 2.65 1.13 1.42 1.61 2.20 437.96 437.64 La139 543.21 480.32 30.86 29.56 403.32 403.40 20.12 34.17 0.52 32.12 28.64 96.42 14.15 0.30 3.90 28.44 24.12 485.21 484.42 Ce140 532.39 473.17 34.20 32.13 393.30 394.63 53.22 154.66 10.17 78.40 82.63 334.78 71.05 8.57 20.80 71.73 171.46 477.33 473.86 Pr141 515.24 453.91 31.01 29.09 375.88 376.82 6.58 18.09 0.13 10.13 11.36 63.85 7.80 0.15 1.97 7.28 12.48 458.69 456.81 Nd146 514.56 451.11 28.37 27.37 373.48 375.16 34.20 99.26 1.43 51.50 59.15 376.72 49.03 1.66 11.78 34.20 72.51 460.83 457.80 Sm147 541.36 471.99 30.80 28.45 389.45 390.00 10.85 35.17 1.85 13.48 18.37 131.83 22.87 1.60 5.41 8.47 31.01 482.59 480.08 Eu153 561.14 486.43 30.39 28.56 400.07 401.76 0.71 3.26 0.20 1.01 1.19 7.56 1.41 0.10 0.36 0.65 1.71 494.89 490.60 Gd157 504.86 440.18 27.27 25.81 363.78 362.27 22.14 38.88 10.16 18.10 31.54 109.72 38.48 6.72 12.06 16.52 53.80 451.16 446.44 Tb159 545.14 468.70 29.08 27.50 384.99 384.24 6.88 7.90 3.96 4.57 8.92 17.44 10.18 2.37 3.85 5.42 15.24 476.10 471.10 Dy163 519.85 450.78 26.84 25.60 367.68 367.56 77.91 71.11 52.19 49.87 100.97 114.26 105.81 29.62 45.68 66.59 166.51 457.40 456.87 Ho165 555.67 477.69 28.92 27.76 389.33 389.18 29.81 22.89 21.11 18.63 37.45 28.68 36.76 11.55 17.26 26.52 59.07 482.87 479.68 Er166 526.81 451.30 27.27 25.87 367.59 367.25 135.42 94.54 100.65 85.75 171.28 108.20 155.99 53.60 78.66 126.85 259.15 458.73 454.49 Tm169 520.80 446.70 27.13 25.93 363.32 363.44 32.01 21.27 25.01 20.91 40.43 24.44 34.52 13.50 19.05 31.66 59.66 451.92 448.61 Yb172 569.81 489.37 30.25 28.93 395.73 395.84 334.05 213.69 276.01 225.31 428.19 267.80 344.90 150.88 208.70 353.86 606.80 497.73 494.46 Lu175 542.36 463.17 27.93 26.27 374.47 375.92 56.56 32.54 44.69 37.86 70.28 41.38 52.76 22.54 31.29 59.53 91.93 467.66 465.59 Hf178 511.77 439.82 26.80 25.34 354.18 359.82 8255 10095 8973 9986 9633 12329 10539 10718 9730 10128 13437 455.37 446.29 Pb208 519.38 443.31 35.19 31.93 354.76 346.05 5.13 10.08 5.12 4.78 12.79 7.98 17.62 3.83 4.32 7.56 37.21 450.61 443.40 Th232 577.81 488.75 28.92 27.04 382.04 381.87 92.13 118.60 96.60 83.61 125.75 94.43 281.82 75.78 73.92 139.18 668.99 489.29 486.68 U238 589.96 496.14 34.13 31.19 386.60 387.97 227.66 351.04 223.67 195.48 249.98 998.36 513.11 299.51 186.03 315.97 1411 496.78 495.17
499 Table 12: Trace element data from the Kawr Suite (kw) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.12, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Details of this procedure are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures.
Sample Nist610a Nist610b Nist612a Nist612b Nist610c Nist610d REE1 REE2 REE3 REE4 REE5 REE6 REE7 REE8 REE9 REE10 REE11 Nist610e Nist610f kw51p Na23 94863 95229 97454 98493 95537 95724 291.75 156.17 192.75 74.68 204.63 481.60 256.85 210.94 94.22 160.69 48.41 94985 94932 Mg24 467.10 470.51 60.61 58.18 463.41 463.19 69.07 24.63 24.11 10.25 144.42 309.81 277.90 68.88 74.38 122.67 2.51 467.30 464.18 Al27 10035 10075 9659 9674 9963 9995 282.85 485.25 296.19 392.55 825.77 1435 2745 1150 653.95 781.13 68.55 9969 10056 Si29 328329 328329 335917 335917 328329 328329 151965 151965 151965 151965 151965 151965 151965 151965 151965 151965 151965 328329 328329 P31 349.10 364.45 54.03 73.20 355.28 353.09 467.78 560.53 310.71 281.46 267.70 216.70 201.91 376.87 691.30 234.69 105.18 316.50 347.46 K39 482.30 488.63 65.15 58.38 489.98 487.19 59.77 17.24 111.30 324.17 66.23 151.52 109.87 226.13 144.31 264.59 7.18 484.05 485.60 Ca43 81438 82375 80978 81894 83835 82933 1256 1709 613.50 671.29 947.21 1196 3914 2253 1530 531.95 313.91 81011 80997 Ti49 423.50 451.38 38.09 36.59 414.08 464.51 17.50 28.92 16.87 12.10 42.86 22.83 150.83 97.72 37.57 24.08 5.42 447.25 413.31 Fe57 509.58 433.04 226.66 241.15 410.64 452.27 630.63 470.78 311.72 404.64 1495.72 2357.82 2496.23 835.15 717.63 1480.71 141.68 446.95 497.82 Rb85 430.53 425.52 33.26 33.57 435.54 438.32 0.44 0.29 0.35 1.61 0.71 0.65 1.30 0.75 0.78 3.75 0.08 429.29 426.93 Sr88 496.18 496.33 72.86 73.21 504.18 503.56 5.60 14.57 10.30 3.60 12.03 13.74 52.89 27.13 7.51 5.77 1.48 496.45 490.28 Y89 452.46 451.26 33.51 32.75 452.47 458.67 2268 4451 2926 2009 2891 1794 5817 4043 3342 1264 629 447.40 444.18 Zr90 445.48 441.82 34.17 34.30 437.89 444.76 489736 495800 499792 488746 468685 467501 468900 497102 486726 466423 498815 532.26 368.11 Nb93 421.96 420.02 33.19 32.94 420.59 427.34 79.53 75.53 80.40 37.83 120.18 44.92 271.79 161.38 53.13 42.71 19.54 416.09 416.22 La139 458.20 458.46 35.16 34.71 459.99 464.42 20.13 29.58 22.90 7.50 16.99 38.34 69.18 42.07 23.53 8.52 2.07 454.15 453.18 Ce140 447.58 445.72 37.82 37.82 448.69 454.01 102.44 197.31 133.28 73.46 120.14 204.90 452.95 252.58 163.63 55.06 22.14 447.04 443.74 Pr141 429.20 429.25 34.98 34.94 432.71 435.73 13.54 27.59 18.12 7.13 17.18 37.84 78.25 47.75 17.96 8.01 2.41 427.41 425.85 Nd146 431.21 430.15 33.43 33.23 431.54 438.02 83.16 166.42 102.99 49.48 112.65 241.17 485.03 286.47 114.25 52.02 15.15 430.46 425.59 Sm147 449.98 455.41 35.07 34.78 452.95 454.62 44.07 115.58 64.73 39.27 90.99 128.69 390.75 218.81 74.60 39.29 12.65 449.25 446.04 Eu153 461.25 461.42 34.82 34.39 464.63 468.35 1.79 2.97 2.68 1.50 2.73 2.89 16.74 9.83 2.58 1.52 0.48 459.84 454.10 Gd157 421.06 422.48 31.73 31.78 421.10 427.05 79.00 211.55 109.82 84.52 153.45 129.98 581.83 328.24 158.78 68.84 25.71 416.93 416.33 Tb159 444.07 445.89 33.98 33.61 446.60 448.22 24.91 62.01 33.47 25.33 45.02 31.96 152.84 87.95 46.38 19.79 8.00 439.77 437.65 Dy163 427.81 430.32 31.19 31.44 431.00 431.79 258.72 582.06 338.47 248.24 417.21 272.51 1170 717.54 443.44 181.08 78.59 423.27 421.55 Ho165 449.73 452.27 34.55 33.83 454.23 455.34 84.79 171.05 109.39 75.92 119.51 72.36 259.13 178.39 131.04 51.17 24.43 445.62 444.11 Er166 426.36 429.18 32.38 31.92 430.34 432.97 350.19 656.81 451.69 299.01 454.31 267.17 824.06 609.32 495.77 193.76 99.38 421.81 421.08 Tm169 421.63 423.82 32.00 31.63 424.28 426.54 79.27 134.83 100.58 64.34 97.04 57.32 149.39 126.56 101.68 41.85 21.99 416.02 414.66 Yb172 463.29 463.61 35.90 35.80 465.01 467.29 786.60 1220 992.53 604.81 919.99 541.53 1215 1181 938.34 409.35 214.98 458.82 456.54 Lu175 434.24 439.66 32.93 32.31 438.61 440.68 106.39 173.23 134.68 84.60 117.36 68.83 158.72 141.76 126.96 53.79 32.34 430.58 429.71 Hf178 418.29 423.00 31.13 31.84 422.14 420.62 13028 13043 15680 12306 13216 14503 14803 13362 9452 12395 15772 417.33 411.31 Pb208 410.60 413.09 38.10 38.63 417.07 419.44 49.67 135.16 65.10 32.20 71.02 89.62 150.79 101.15 55.97 43.03 6.76 413.84 405.94 Th232 449.53 456.88 34.62 33.77 457.75 459.97 707.37 2046 899.51 320.41 601.30 279.75 495.87 694.56 616.18 127.00 59.85 446.23 440.56 U238 455.08 458.35 38.12 37.74 461.27 464.61 2434 3225 3247 787.26 2443 1282 2486 1923 1098 524.46 329.48 453.10 451.62
500 Table 13: Trace element data from the Idah Suite (id) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.13, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Details of this procedure are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures.
Sample Nist610a Nist610b Nist612a Nist612b Nist610c Nist610d REE1 REE2 REE3 REE4 REE5 REE6 REE7 REE8 REE9 REE10 REE11 REE12 Nist610e Nist610f id159 Na23 94814 94338 98090 97309 96043 95509 134.40 21.62 184.02 26.59 98.69 61.46 404.66 466.30 193.62 281.81 56.22 252.69 95157 94923 Mg24 459.22 468.55 24.26 57.01 477.35 456.61 151.25 28.00 178.99 62.92 38.43 20.19 115.76 68.29 111.98 106.23 11.85 324.84 469.09 459.08 Al27 10004 9941 10160 10146 10093 9906 2009 208.82 1560 468.59 167.13 137.73 1464 341.51 344.74 715.15 43.21 1522 9976 9848 Si29 328329 328329 335917 335917 328329 328329 151965 151965 151965 151965 151965 151965 151965 151965 151965 151965 151965 151965 328329 328329 P31 345.67 333.78 24.63 49.80 357.73 359.89 600.30 773.50 3252.68 406.31 3654.89 922.81 881.94 1908.74 438.53 480.81 1178.70 1703.87 339.17 358.86 K39 476.53 486.26 31.54 66.30 490.66 493.98 186.00 62.74 708.28 75.18 82.06 68.67 89.13 255.68 188.51 81.41 57.99 217.88 474.70 492.08 Ca43 83140 81626 86865 85880 81797 82597 7196 1821 10919 1249 11594 3059 6801 7635 875.64 1983 3728 7117 82318 81577 Ti49 423.62 453.66 4.08 38.36 418.85 437.00 50.55 14.00 60.51 268.67 19.03 12.94 56.24 18.04 18.39 32.08 11.59 67.60 427.13 449.73 Fe57 489.53 383.48 105.75 98.23 496.67 380.47 5010 715.07 6695 1074 320.29 6705 3883 1189 878.00 1595 112.11 4645 360.05 498.40 Rb85 427.60 434.22 0.94 32.81 439.22 438.41 4.24 0.46 4.22 0.68 0.44 0.65 0.66 0.55 0.63 0.49 0.13 2.74 424.07 422.78 Sr88 493.92 499.66 44.00 76.30 516.29 502.11 96.43 3.78 14.14 7.81 12.90 3.79 101.02 38.71 7.85 18.65 2.51 54.51 489.53 483.00 Y89 446.23 454.20 0.87 36.94 466.91 455.33 7775 1778 3110 2762 1339 2398 5856 2859 3062 3632 1620 4933 442.72 433.80 Zr90 428.02 442.82 0.92 37.77 470.61 466.40 541103 553580 592119 542325 552309 571469 545322 581416 570426 553413 561190 516440 364.36 396.07 Nb93 417.17 422.70 0.80 34.66 431.85 423.94 317.26 22.52 74.58 47.44 27.69 11.84 192.42 40.50 3.92 47.81 4.69 60.70 412.84 407.86 La139 455.91 460.27 0.85 37.60 474.07 465.33 75.60 17.64 25.35 8.15 138.90 17.07 568.93 1039 14.91 22.91 73.06 37.53 448.67 441.81 Ce140 444.75 450.67 0.86 38.92 462.70 456.22 447.50 96.36 111.57 67.67 299.84 80.59 876.49 1070 51.14 100.19 160.73 190.48 438.88 436.02 Pr141 426.83 433.72 0.88 36.99 445.31 437.73 89.37 5.74 17.14 6.88 40.79 7.27 104.92 96.41 5.89 13.78 22.65 26.48 422.74 417.64 Nd146 426.42 435.86 0.89 35.97 447.05 438.04 550.66 31.46 109.63 46.87 177.69 48.22 462.85 377.84 33.99 78.04 118.24 157.02 423.39 416.37 Sm147 447.12 453.05 0.72 37.35 469.68 460.43 390.12 19.28 76.28 46.86 39.05 35.59 181.80 79.78 21.61 56.09 30.42 103.50 441.17 437.50 Eu153 458.82 463.28 0.99 36.80 478.74 470.05 9.67 2.41 3.39 2.68 3.30 4.01 4.27 1.97 3.82 2.16 2.55 3.71 453.68 446.95 Gd157 416.85 422.58 0.73 34.37 439.03 428.89 594.91 54.70 145.94 105.37 52.11 93.58 266.52 112.89 64.46 119.87 60.29 193.69 412.46 403.88 Tb159 440.28 445.17 0.75 36.84 462.97 452.43 155.83 17.90 42.36 35.65 14.37 27.55 82.28 30.59 22.28 39.90 16.28 59.17 435.60 427.11 Dy163 424.83 430.46 0.77 34.47 446.21 434.62 1204 196.95 391.74 364.56 149.06 281.10 752.02 311.00 272.56 425.73 176.26 608.50 418.90 411.07 Ho165 448.22 452.61 0.75 37.28 471.21 459.58 289.69 64.83 114.36 108.98 49.22 89.52 211.90 101.80 103.36 129.41 59.13 183.56 442.35 433.04 Er166 424.66 430.29 0.72 35.20 446.02 433.84 920.75 271.66 435.65 427.87 201.69 348.52 783.43 420.19 486.78 528.45 248.57 725.44 417.88 412.05 Tm169 418.75 422.52 0.73 34.55 441.28 429.45 171.26 62.80 86.36 95.80 45.70 75.35 169.33 91.81 116.13 120.42 54.35 156.27 412.75 405.52 Yb172 459.36 463.98 0.73 38.65 482.81 469.58 1446 639.81 760.82 947.87 471.39 751.77 1675.07 874.83 1175 1222 528.42 1483 453.05 446.67 Lu175 433.77 437.86 0.70 35.62 456.92 445.10 179.65 89.61 123.46 121.53 69.14 103.43 212.30 140.86 205.83 167.10 85.97 199.64 425.96 419.22 Hf178 417.48 420.77 0.72 34.49 438.18 427.71 10958 8741 10448 7863 7914 8549 12407 10189 13834 12720 9103 9947 412.84 400.82 Pb208 407.82 419.44 2.23 39.04 430.28 424.52 88.91 24.88 13.93 49.05 11.89 16.23 50.95 27.58 41.19 31.06 8.26 37.60 409.09 401.93 Th232 449.77 455.76 1.09 36.49 473.25 465.20 922.13 499.61 276.26 396.37 164.04 295.93 720.93 445.72 629.68 342.51 170.21 791.61 434.10 430.12 U238 451.03 464.88 1.08 38.50 480.44 472.34 1191 537.14 447.62 573.34 335.66 465.22 2673 1188 1255 1299 274.67 1660 453.24 442.19
501 Table 14: Trace element data from the Al Khushaymiyah Suite (ky) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.14, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Details of this procedure are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures.
Sample Nist610a Nist610b Nist612a Nist612b Nist610c Nist610d REE1 REE2 REE3 REE4 REE5 REE6 REE7 Nist610e Nist610f ky129 Na23 92970 95354 99089 99552 93875 94217 47.54 32.23 40.64 84.43 39.84 17.13 38.66 94808 96674 Mg24 450.83 464.02 57.12 58.71 453.03 452.87 86.06 45.52 203.75 175.85 16.46 206.71 70.71 466.88 476.13 Al27 9975 9886 9631 9024 9723 9691 274.63 250.35 346.47 454.81 121.26 595.01 192.22 10092 10213 Si29 328329 328329 335917 335917 328329 328329 151965 151965 151965 151965 151965 151965 151965 328329 328329 P31 297.20 348.40 43.55 51.58 406.12 387.34 620.68 233.71 68.88 456.35 365.63 173.73 337.50 313.96 327.34 K39 493.30 468.85 64.80 60.48 468.88 483.61 30.23 18.79 23.75 45.77 7.34 32.96 39.32 490.15 494.76 Ca43 82883 78906 80237 76689 80570 82680 202.65 714.30 342.57 878.49 333.23 386.16 257.33 82146 82260 Ti49 440.36 415.66 34.14 31.84 430.17 437.11 40.82 18.34 14.49 15.93 18.66 10.35 29.72 431.89 440.13 Fe57 507.18 417.75 118.16 106.01 422.46 463.09 527.16 659.91 884.85 981.32 332.54 1617 277.48 437.81 493.89 Rb85 469.67 386.83 28.62 31.11 422.84 429.41 0.64 0.16 0.05 0.40 0.15 0.36 0.25 438.43 439.30 Sr88 548.35 443.05 66.67 66.45 492.11 501.26 6.23 6.00 4.47 9.59 3.42 0.99 1.80 506.29 502.94 Y89 492.59 402.02 30.69 29.51 451.89 451.46 3950 2264 363.96 2208 1939 902.64 2181 454.66 455.25 Zr90 475.95 406.63 30.05 29.85 433.57 430.43 490837 497403 487615 507917 480286 505590 498586 462.02 435.64 Nb93 457.67 375.48 30.05 30.08 417.91 423.13 10.28 2.17 0.91 5.39 4.17 1.52 3.72 424.22 424.24 La139 528.98 398.83 30.68 30.88 454.41 460.85 38.22 57.54 48.86 70.09 31.54 6.97 15.53 468.19 463.10 Ce140 515.35 391.51 33.09 34.03 442.89 451.39 428.61 228.76 146.28 335.72 206.69 49.29 149.02 456.04 456.62 Pr141 504.10 371.93 30.54 31.16 424.16 430.33 11.21 16.24 10.96 19.92 10.71 2.29 4.43 441.41 438.30 Nd146 502.95 366.12 27.98 29.07 421.87 429.05 66.08 78.44 45.07 96.91 49.61 12.90 25.06 444.29 440.19 Sm147 522.31 382.28 29.83 30.36 442.97 450.28 51.96 29.92 6.84 28.07 18.58 6.44 16.18 464.83 458.41 Eu153 546.24 393.58 29.98 30.39 453.78 463.80 18.05 10.05 3.07 7.37 6.33 1.86 6.99 473.45 471.84 Gd157 492.30 354.07 26.66 27.11 413.57 417.02 161.44 82.42 11.77 71.22 65.18 23.32 67.16 433.58 428.84 Tb159 528.98 377.58 28.77 29.64 438.91 444.33 45.20 23.55 3.24 21.11 19.45 7.45 20.93 456.08 451.66 Dy163 506.92 359.48 26.34 27.02 420.63 426.81 453.82 250.98 34.83 224.82 206.81 84.62 231.54 440.24 435.32 Ho165 537.80 382.16 29.43 29.38 445.55 451.61 146.59 82.29 12.17 77.68 69.48 30.89 80.00 462.37 459.12 Er166 508.27 359.86 27.80 27.47 420.41 426.94 577.40 331.89 55.89 325.73 285.52 136.75 332.58 438.14 436.36 Tm169 508.41 356.80 27.18 27.38 414.68 421.88 130.60 76.24 14.30 74.65 65.00 33.04 76.74 433.28 429.44 Yb172 555.02 387.80 30.02 30.21 451.23 460.97 1371.23 815.02 169.92 762.63 686.09 350.28 820.02 475.85 474.70 Lu175 522.84 369.63 27.88 28.07 429.53 436.33 179.48 110.65 28.86 114.77 97.07 55.04 114.99 448.53 444.17 Hf178 495.12 348.31 26.41 27.54 408.55 415.83 7416 9254 10935 9354 8579 9941 7614 433.64 426.39 Pb208 497.23 346.59 31.40 36.51 401.65 408.34 152.04 35.53 12.84 88.64 76.18 13.33 46.87 428.01 427.62 Th232 554.16 374.70 28.75 29.27 446.62 455.06 2865 612.51 119.83 1658 1396 199.75 883.74 467.51 458.78 U238 558.93 381.00 31.04 35.11 451.19 464.68 1955 743.74 739.35 1395 1022 324.90 818.87 472.53 467.51
502 Anorogenic Magmatism (<600 Ma) Post-Arabian Shield Terrane Accretion
503 Table 15: Trace element data from the Malik Granite (kg) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.15, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Details of this procedure are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures.
Sample Nist610a Nist610b Nist612a Nist612b Nist610c Nist610d REE1 REE2 REE3 REE4 REE5 Nist610e Nist610f kg150 Na23 92457 95125 98111 95367 93704 92346 145.80 27.16 56.93 74.44 38.85 95912 96615 Mg24 463.70 458.87 58.62 58.83 437.71 443.82 93.75 7.28 183.52 11.39 9.52 476.81 478.36 Al27 9959 9959 9547 8822 9607 9475 370.19 37.57 410.30 113.96 109.75 10130 10327 Si29 328329 328329 335917 335917 328329 328329 151965 151965 151965 151965 151965 328329 328329 P31 367.00 362.23 50.27 65.80 368.58 386.73 575.55 397.95 317.22 421.95 281.94 320.74 335.58 K39 490.62 469.75 68.32 61.39 472.37 467.62 281.10 5.84 282.47 14.26 6.59 486.62 505.09 Ca43 83074 80259 77903 73568 80047 79302 1475 252.88 427.69 350.03 299.86 83238 82693 Ti49 443.08 399.93 23.82 33.02 458.25 451.08 26.46 4.25 24.11 11.33 6.55 439.43 419.60 Fe57 490.11 430.68 117.60 126.59 452.88 419.19 382.85 75.03 714.42 70.04 142.98 493.72 452.32 Rb85 486.95 388.00 27.60 30.08 416.91 427.98 1.75 0.08 3.03 0.33 0.05 441.95 438.90 Sr88 570.09 447.36 62.58 64.24 487.50 492.36 5.72 0.76 1.36 2.37 1.19 506.77 507.43 Y89 517.55 408.12 29.64 28.60 443.33 444.70 3579 1638 1833 7916 1510 460.67 454.28 Zr90 499.33 398.72 29.44 29.14 427.92 431.85 504166 524141 551197 545989 529246 458.46 439.99 Nb93 478.48 378.95 29.12 29.06 412.85 420.08 35.96 16.61 13.98 29.69 12.65 425.13 425.58 La139 564.38 404.84 28.97 29.47 447.86 456.70 52.57 1.38 28.45 15.52 3.02 468.79 465.04 Ce140 555.38 393.80 31.23 32.86 437.36 450.37 280.50 41.74 117.57 191.73 39.47 458.98 455.47 Pr141 543.82 374.98 28.79 29.16 415.01 425.86 26.33 1.41 10.65 10.02 2.22 444.37 441.21 Nd146 547.73 369.47 26.94 27.06 412.46 421.57 164.46 9.51 59.07 70.51 15.29 449.70 442.81 Sm147 569.18 386.04 28.48 28.36 429.58 440.46 85.10 8.09 27.34 78.73 12.60 469.06 465.35 Eu153 600.06 397.36 28.34 28.16 441.19 452.46 6.18 0.67 1.27 4.95 1.03 481.21 475.88 Gd157 535.19 357.07 26.11 25.83 400.75 411.42 188.37 23.92 77.94 315.72 30.79 438.14 433.24 Tb159 576.55 381.58 27.35 27.33 426.24 435.54 54.53 9.67 23.62 99.55 11.13 462.59 455.35 Dy163 556.97 363.23 25.25 25.38 408.05 417.36 522.96 129.41 240.75 1012 132.17 444.22 442.19 Ho165 590.95 385.76 27.90 27.38 432.73 441.81 149.15 52.81 75.04 315.99 50.30 470.13 462.50 Er166 561.75 363.41 25.51 25.51 408.09 416.68 519.64 264.41 275.29 1154 240.34 444.85 441.08 Tm169 559.64 360.46 25.82 25.71 401.96 412.27 100.52 69.08 54.46 202.29 61.04 439.93 434.04 Yb172 614.93 391.49 27.94 27.95 438.95 448.85 889.23 756.79 488.69 1572.06 661.96 484.03 479.29 Lu175 581.78 370.75 26.11 26.28 419.60 428.60 103.83 121.53 63.75 252.08 107.14 454.12 448.19 Hf178 544.01 350.84 25.89 25.99 398.46 409.76 6488 17006 7499 7229 15947 437.26 430.74 Pb208 566.94 344.17 30.43 33.97 394.49 404.39 11.95 12.84 7.65 21.26 14.19 436.89 426.67 Th232 619.57 377.46 26.96 27.17 438.62 446.30 180.54 237.71 153.25 449.08 242.67 473.38 461.77 U238 637.67 380.56 29.92 33.17 442.12 459.27 589.99 883.83 363.33 827.51 750.51 477.26 471.56
504 Table 16: Trace element data from the Admar Suite (ad) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.16, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Details of this procedure are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures.
Sample Nist610a Nist610b Nist612a Nist612b Nist610c Nist610d REE1 REE2 REE3 REE4 REE5 REE6 REE7 REE8 REE9 REE10 Nist610e Nist610f ad194 Na23 94627 94594 97852 95648 95787 95616 3.78 3.65 5.47 6.41 6.44 6.63 5.00 5.91 7.78 10.06 95233 94782 Mg24 465.66 463.12 61.91 58.55 466.97 468.26 1.20 29.24 0.21 0.23 0.18 0.77 0.66 0.23 0.61 3.05 464.89 466.93 Al27 9885 10051 9864 9859 10138 10132 4.35 61.74 8.36 4.12 3.74 14.64 2.65 5.60 13.33 11.77 10149 10029 Si29 328329 328329 335917 335917 328329 328329 151965 151965 151965 151965 151965 151965 151965 151965 151965 151965 328329 328329 P31 339.78 344.33 46.21 60.02 351.63 338.66 181.62 159.33 198.75 176.95 156.86 163.86 185.10 174.75 151.02 156.29 335.96 350.26 K39 489.15 482.52 58.34 61.29 488.10 494.71 2.67 2.72 2.65 2.70 2.74 2.56 2.57 2.65 3.90 2.69 475.31 485.37 Ca43 81851 81383 81094 81410 82675 83392 150.06 72.47 83.87 83.57 77.26 71.57 82.08 76.06 80.17 81.58 82097 81803 Ti49 434.92 426.40 37.43 37.49 438.67 446.17 17.10 15.51 21.16 17.16 14.56 23.64 19.05 17.70 15.06 22.48 424.67 432.36 Fe57 440.45 457.21 99.62 398.65 539.00 290.03 273.42 460.87 315.66 285.49 268.40 250.42 215.04 301.70 754.89 289.77 433.94 506.71 Rb85 433.23 431.75 32.52 33.28 433.29 434.00 0.07 0.06 0.11 0.08 0.10 0.12 0.08 0.14 0.07 0.12 431.04 426.77 Sr88 497.83 495.35 73.24 74.42 501.84 502.37 0.23 0.24 0.23 0.25 0.16 0.14 0.16 0.15 0.21 0.19 500.41 497.49 Y89 442.21 455.57 35.27 35.02 455.45 457.34 661.55 626.45 532.05 561.07 455.81 424.90 517.80 722.59 405.88 429.92 457.35 452.88 Zr90 432.33 444.19 35.36 35.80 447.49 456.87 522561 521221 522024 532654 525680 535619 529971 537623 544628 559072 390.45 425.40 Nb93 418.13 417.98 33.45 33.41 422.99 424.77 0.58 1.39 0.87 0.72 0.79 0.64 0.88 0.93 0.69 0.64 421.63 420.52 La139 453.94 458.30 35.53 35.20 461.89 461.76 0.61 0.27 1.02 0.27 0.01 0.27 0.04 0.02 0.19 0.09 464.91 457.84 Ce140 447.79 445.82 37.25 37.18 451.77 450.27 30.75 40.63 48.66 28.06 31.55 25.73 54.36 44.07 29.06 27.89 450.60 447.24 Pr141 428.22 428.28 34.82 34.90 434.83 433.00 0.41 0.22 0.46 0.24 0.10 0.35 0.21 0.30 0.14 0.15 434.76 427.12 Nd146 427.34 431.40 34.22 33.85 437.24 433.70 5.45 3.13 4.85 3.40 1.95 4.53 3.93 5.42 2.12 2.49 438.98 431.07 Sm147 447.19 452.84 35.32 35.38 455.71 456.03 8.02 5.42 6.05 5.79 3.81 5.23 6.66 8.32 3.58 4.14 461.08 450.19 Eu153 461.43 459.38 35.01 35.02 466.44 464.72 2.68 1.23 1.38 1.87 1.08 2.14 1.44 2.03 1.13 1.52 467.89 459.81 Gd157 413.98 422.33 32.69 32.77 425.75 424.88 28.55 21.77 21.14 21.46 16.22 17.12 22.65 29.90 14.45 17.18 429.01 420.90 Tb159 437.54 445.80 34.73 34.76 448.75 447.12 7.67 6.58 5.77 6.15 4.72 4.71 6.09 8.15 4.26 4.57 452.42 444.83 Dy163 421.23 428.46 32.53 31.96 432.86 429.89 74.36 69.09 58.42 60.61 48.09 46.62 60.33 81.07 43.20 46.59 438.02 428.06 Ho165 444.67 451.84 35.14 35.04 455.00 452.58 23.68 22.90 19.08 20.10 16.19 15.40 19.06 26.71 14.59 15.57 460.21 451.18 Er166 422.28 427.93 33.47 33.22 432.54 430.08 93.19 92.10 76.99 81.60 67.47 61.32 75.96 105.57 59.96 63.50 437.37 428.50 Tm169 416.23 421.51 32.88 32.58 425.55 424.00 18.72 18.57 16.00 16.56 14.22 12.89 15.89 21.46 12.61 13.20 431.60 420.94 Yb172 457.41 464.59 36.13 35.57 467.09 462.64 173.31 171.87 152.24 156.56 136.02 125.13 150.74 201.51 121.71 124.23 472.96 463.12 Lu175 429.44 439.13 33.60 33.25 440.79 437.46 31.16 30.35 27.22 28.92 24.44 22.37 26.52 35.85 22.12 23.15 445.16 436.65 Hf178 412.62 418.37 33.34 32.59 421.96 422.57 7644 8206 7639 7712 7963 7334 7535 7644 7954 7772 427.61 420.40 Pb208 415.24 412.40 36.88 36.90 415.00 410.14 1.74 2.84 2.33 1.46 1.43 1.20 2.19 2.61 1.46 1.17 411.30 412.26 Th232 444.71 450.05 34.32 34.60 456.57 457.28 32.79 43.64 43.70 28.37 28.10 23.63 44.06 51.31 24.50 26.23 464.79 451.08 U238 460.31 454.33 37.06 36.88 458.79 456.75 34.88 65.31 52.55 36.59 40.92 33.11 50.93 57.61 35.65 34.56 463.20 454.01
505 Table 16 (continued): Trace element data from the Admar Suite (ad) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.16, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Details of this procedure are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures.
Sample Nist610g Nist610h Nist612c Nist612d Nist610i Nist610j REE11 REE12 REE13 REE14 REE15 REE16 REE17 REE18 REE19 Nist610k Nist610l ad194 Na23 94782 94527 94972 97567 95650 96045 3.65 6.23 3.54 12.50 3.37 10.47 6.64 15.50 4.65 95607 94485 Mg24 466.93 465.35 59.38 58.04 465.51 463.52 0.20 1.15 25.82 0.58 1.16 0.30 0.20 0.19 43.80 464.47 466.56 Al27 10029 9976 10215 9745 9916 9923 4.45 44.76 51.51 5.52 7.95 4.84 2.51 11.79 225.24 10024 10042 Si29 328329 328329 335917 335917 328329 328329 151965 151965 151965 151965 151965 151965 151965 151965 151965 328329 328329 P31 350.26 342.41 60.42 50.42 338.79 345.75 207.15 215.23 195.75 158.99 140.51 141.07 170.06 145.87 426.16 337.33 346.83 K39 485.37 486.75 57.29 62.05 492.85 494.07 2.51 27.72 5.49 2.57 2.44 2.40 2.53 2.56 16.99 484.47 483.53 Ca43 81803 81398 81994 81115 81246 82761 76.93 85.19 78.12 71.36 75.03 74.56 86.53 81.65 721.53 81331 82241 Ti49 432.36 434.53 38.56 36.10 444.34 437.54 14.83 17.68 19.31 18.74 18.49 14.44 15.43 25.47 18.69 432.00 432.14 Fe57 506.71 469.58 253.32 339.45 463.69 373.17 336.36 192.05 416.80 328.88 297.40 309.95 334.91 381.86 553.39 404.66 522.05 Rb85 426.77 432.59 31.56 33.25 431.56 434.49 0.10 0.25 0.17 0.16 0.11 0.10 0.17 0.04 0.13 429.98 431.04 Sr88 497.49 494.78 74.38 72.31 496.29 498.06 0.16 0.34 0.33 0.10 0.12 0.12 0.17 0.18 1.72 495.51 499.66 Y89 452.88 448.36 36.59 34.38 440.84 448.12 1338 855.39 1051 540.74 392.65 396.90 1094 357.09 817.95 452.41 450.63 Zr90 425.40 433.27 6.60 26.86 455.30 467.56 553514 550846 556985 559281 566963 558572 556089 560679 578897 448.23 406.89 Nb93 420.52 419.77 34.12 32.82 415.75 418.43 1.91 1.41 1.96 0.81 0.66 0.76 0.69 0.59 0.92 419.06 420.97 La139 457.84 455.93 36.24 35.08 452.06 454.64 0.26 0.57 0.67 0.02 0.02 0.05 0.25 0.12 8.57 459.20 458.21 Ce140 447.24 447.55 37.30 37.06 448.54 444.31 69.75 50.93 67.04 32.83 28.32 32.47 47.48 24.01 73.86 449.39 447.28 Pr141 427.12 428.84 35.43 34.49 429.16 428.67 0.60 0.51 0.70 0.17 0.09 0.11 0.86 0.13 2.43 430.97 429.47 Nd146 431.07 429.28 34.50 33.14 427.29 425.47 9.22 7.45 8.82 3.24 1.72 1.88 14.15 2.10 17.40 433.42 431.16 Sm147 450.19 450.65 35.89 35.27 444.45 443.44 14.48 10.41 11.99 5.33 3.55 3.54 17.86 3.53 13.11 453.17 451.95 Eu153 459.81 461.40 35.66 34.61 458.08 456.75 2.99 2.51 2.63 1.56 1.22 1.02 4.33 1.37 3.27 461.30 463.26 Gd157 420.90 420.22 33.97 32.24 412.60 414.18 53.06 36.20 42.04 20.52 14.18 14.26 54.38 13.87 38.18 421.84 421.87 Tb159 444.83 441.85 35.76 34.26 435.48 436.79 14.94 9.97 11.94 5.84 4.17 4.19 13.91 3.85 9.83 446.47 443.38 Dy163 428.06 425.56 33.19 32.17 419.82 418.03 151.14 98.06 119.25 58.71 41.97 42.38 130.94 38.88 92.41 430.36 427.51 Ho165 451.18 450.03 36.17 34.60 439.83 442.69 49.04 31.28 39.14 19.55 13.87 14.36 40.46 13.00 29.26 452.87 450.91 Er166 428.50 424.27 34.19 32.33 418.57 418.42 191.76 121.94 151.79 80.51 57.04 58.19 154.23 52.48 115.43 428.96 427.85 Tm169 420.94 419.29 33.68 32.50 412.56 413.44 37.65 24.42 29.60 16.50 11.99 12.41 30.46 11.03 22.93 423.48 421.32 Yb172 463.12 459.15 37.80 35.96 454.98 454.64 338.71 224.36 268.16 157.55 114.22 119.85 278.01 106.70 211.23 464.75 462.64 Lu175 436.65 434.30 34.62 32.91 427.91 426.57 59.04 37.68 47.15 29.42 20.54 20.87 47.23 18.69 37.97 437.90 436.28 Hf178 420.40 420.28 33.80 32.02 408.69 408.15 8031 7939 7939 7903 7756 7692 7318 7260 7557 423.53 417.52 Pb208 412.26 411.40 35.50 37.26 415.73 417.47 4.87 5.22 6.02 1.61 1.15 1.43 3.35 1.15 5.19 411.39 413.45 Th232 451.08 448.75 35.51 34.27 442.46 442.84 100.27 88.16 110.11 31.88 24.55 26.67 61.73 21.82 65.35 455.93 450.53 U238 454.01 458.66 36.20 36.20 452.70 455.56 103.42 104.39 111.63 42.64 34.81 39.14 58.56 30.83 65.68 460.61 455.40
506 Table 17: Trace element data from the Al Bad Granite Super Suite (abg) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.17, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Details of this procedure are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures.
Sample Nist610a Nist610b Nist612a Nist612b Nist610c Nist610d REE1 REE2 REE3 REE4 REE5 REE6 REE7 REE8 REE9 REE10 REE11 REE12 Nist610e Nist610f abg179 Na23 95558 96289 96902 97614 95509 94726 151.43 80.82 362.29 133.36 175.42 313.96 425.36 153.45 52.86 228.82 437.25 308.31 96099 94213 Mg24 481.50 473.30 55.35 56.43 457.91 444.15 142.66 31.14 1543 217.20 1272 152.97 119.98 40.58 118.18 309.80 126.84 544.83 484.85 459.34 Al27 10205 10066 9491 9472 9712 9833 439.56 351.40 3342 660.22 1798 855.88 1272 628.49 1384 1436 1227 3018 10182 10039 Si29 328329 328329 335917 335917 328329 328329 151965 151965 151965 151965 151965 151965 151965 151965 151965 151965 151965 151965 328329 328329 P31 324.77 315.94 41.66 53.44 390.07 372.49 1970.50 859.53 534.76 1096.97 1126.36 1027.66 695.55 1672 914.99 555.92 1055.00 884.02 330.16 327.31 K39 491.54 479.15 57.45 61.06 477.80 480.54 168.14 80.28 539.65 67.63 155.09 269.06 203.19 153.31 551.95 609.10 112.29 314.79 496.37 484.58 Ca43 80696 81701 78194 78716 81262 81874 390.37 501.15 1309 1172 1923 757.49 2495 3656 273.05 936.44 1534 1144 81566 82483 Ti49 443.94 413.08 43.65 40.63 437.31 444.21 7.27 74.26 26.88 224.75 36.47 31.60 21.66 18.90 8.16 24.84 37.31 29.23 432.18 433.09 Fe57 448.90 438.44 182.41 186.37 465.76 474.22 459.76 173.60 2734 560.80 1427 1235 601.84 263.08 376.58 951.46 304.04 2231 436.77 469.43 Rb85 430.36 395.12 29.40 30.05 419.09 426.23 1.66 0.52 5.16 0.82 1.19 0.62 1.07 1.05 4.11 7.33 1.08 2.58 447.28 439.27 Sr88 498.82 453.61 62.79 65.73 481.05 496.62 6.90 4.45 36.06 20.36 5.52 5.98 64.89 1.83 3.85 30.34 70.70 38.33 513.92 509.29 Y89 450.97 411.66 29.17 29.53 433.12 449.89 4331 4613 6472 4277 3694 3747 8753 5724 5028 4722 8761 6723 470.25 456.06 Zr90 436.04 404.58 28.34 31.16 423.19 445.44 465892 537080 479566 519291 519771 539981 523676 563477 583592 545805 514599 470214 488.64 433.95 Nb93 419.12 383.94 28.33 30.17 406.62 418.91 13.88 30.08 63.40 21.31 14.03 22.20 64.65 10.92 16.15 27.93 206.65 24.93 432.79 428.13 La139 467.57 407.82 29.58 31.40 435.57 454.22 846.95 68.49 25.72 109.30 35.08 13.09 67.23 40.75 12.59 18.40 78.82 26.61 483.36 474.95 Ce140 455.86 396.63 32.56 34.13 432.46 443.51 3106 2035 3940 507.88 2290 1486 866.88 475.57 461.28 670.98 2803 1461 472.44 464.50 Pr141 441.15 380.25 29.57 31.08 410.39 424.23 341.73 27.85 31.82 38.23 14.09 10.61 60.24 13.05 7.30 13.42 68.43 28.42 456.30 448.99 Nd146 438.29 379.59 27.46 29.04 407.67 422.45 1425.98 150.89 194.00 177.87 80.54 69.50 342.15 70.78 53.50 73.07 349.83 173.41 457.69 449.38 Sm147 460.08 395.32 29.34 30.80 425.25 443.40 347.58 103.62 171.27 87.07 69.21 75.58 275.33 42.62 71.45 68.16 264.23 170.43 479.39 468.89 Eu153 475.17 406.03 28.78 30.77 437.07 453.66 11.09 5.09 8.03 4.05 5.44 3.83 12.73 2.37 5.14 3.74 12.70 8.61 493.36 483.12 Gd157 427.24 369.31 27.68 27.68 394.96 413.74 282.25 184.18 277.05 154.20 150.06 150.88 437.04 140.21 238.89 162.11 443.75 342.55 447.47 437.36 Tb159 456.69 390.98 28.00 29.55 417.70 438.66 59.44 49.09 71.82 43.37 44.14 42.36 112.72 47.66 73.59 46.86 123.84 88.51 475.47 463.01 Dy163 437.31 374.50 26.25 27.67 401.57 420.45 497.70 480.62 669.63 439.58 444.73 412.00 1017 554.67 696.44 485.69 1169 785.32 457.32 445.41 Ho165 464.55 396.01 28.01 29.78 423.93 444.44 152.58 162.57 219.68 148.40 144.56 135.85 309.42 208.51 206.79 169.59 352.50 235.39 483.88 470.31 Er166 438.46 374.56 26.56 27.70 400.01 420.72 620.99 686.04 955.01 642.48 576.42 580.28 1295 915.61 750.79 745.08 1333 891.47 458.49 445.31 Tm169 434.98 368.98 26.44 27.84 397.04 415.51 128.86 151.89 209.32 140.19 124.31 132.99 283.41 192.93 151.50 174.86 288.21 184.86 452.26 439.88 Yb172 476.63 403.50 29.38 30.70 433.24 452.00 1179 1466 1995 1327 1252 1326 2676 1736 1390 1776 2873 1693 498.34 484.08 Lu175 449.37 381.76 26.56 28.23 410.20 431.33 205.49 226.61 353.28 233.30 169.58 229.32 472.69 308.23 193.74 264.28 357.59 291.16 467.88 455.86 Hf178 427.91 359.22 26.49 27.51 394.23 412.50 9688 11586 10935 11382 10641 12541 13665 12721 10495 12733 11005 10720 446.99 435.64 Pb208 429.17 354.01 32.01 35.26 391.97 403.45 23.91 25.17 106.43 45.14 19.36 36.68 134.83 29.58 19.69 95.41 178.24 76.10 444.93 437.89 Th232 468.10 387.83 27.54 29.29 424.53 451.17 417.59 559.74 1341 497.05 352.49 364.67 1298 576.43 453.24 622.53 2178 565.43 487.87 472.71 U238 474.50 389.34 31.67 33.01 443.25 451.79 581.27 813.86 1390 829.41 583.99 715.92 1978 597.99 382.84 1048 2299 722.90 496.45 478.18
507 Table 18: Trace element data from the Al Hawiyah Suite (hwg) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.18, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Details of this procedure are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures.
Sample Nist610a Nist610b Nist612a Nist612b Nist610c Nist610d REE1 G1 REE2 G1 REE3 G1 REE4 G1 REE5 G3 REE6 G3 REE7 G3 Nist610e Nist610f hwg07 Na23 94232 93535 96734 98244 94884 96215 28.30 22.77 63.32 44.45 263.21 1073 251.70 95702 94688 Mg24 464.66 454.77 55.87 57.12 465.71 464.91 422.48 722.53 1068 554.68 813.86 528.27 83.10 457.86 475.35 Al27 9890 9730 9222 9382 10101 9955 619.44 1104 1393 876.94 1517 1120 547.20 10081 9988 Si29 328329 328329 335917 335917 328329 328329 151965 151965 151965 151965 151965 151965 151965 328329 328329 P31 339.38 352.00 32.04 58.54 385.05 375.17 217.78 263.44 251.91 177.94 233.38 661.31 791.38 321.64 325.02 K39 482.96 485.57 63.08 63.44 487.48 490.67 7.46 43.14 8.55 45.41 93.13 32.41 33.79 485.14 484.41 Ca43 80980 81431 79216 81371 82723 82119 161.14 481.49 156.68 216.21 2218 3325 767.41 81822 81476 Ti49 460.30 431.77 38.73 38.78 438.18 436.01 18.16 98.07 11.80 16.41 27.78 33.80 13.27 442.88 420.67 Fe57 451.35 471.36 223.49 218.73 422.43 414.47 731.56 1478 1998 1586 1961 2203.26 576.54 432.27 524.51 Rb85 435.50 441.04 34.11 34.12 441.79 441.11 0.14 0.88 0.18 0.11 1.28 0.43 0.29 424.40 423.83 Sr88 501.12 507.02 72.05 73.91 518.26 506.22 1.14 4.29 2.06 0.64 28.11 60.67 14.27 489.92 486.87 Y89 453.53 457.38 32.11 32.94 471.55 456.49 1602 2231 1143 1600 3589 7005 4800 441.34 442.52 Zr90 444.27 447.71 32.29 34.30 461.65 445.99 505101 501695 493006 481476 501325 529175 527069 433.24 429.66 Nb93 426.02 429.14 32.54 32.97 436.61 426.99 17.64 199.95 15.92 20.39 73.00 333.26 214.45 413.13 410.17 La139 466.19 471.01 34.65 35.52 480.65 465.14 2.48 20.20 3.92 7.44 372.30 30.41 25.15 450.74 442.83 Ce140 455.26 463.24 38.50 39.16 463.63 459.53 15.60 59.76 29.17 29.12 605.27 132.34 116.90 440.65 433.61 Pr141 436.60 442.56 34.94 35.81 448.28 437.41 1.78 5.72 2.98 1.60 71.88 14.53 14.37 424.03 416.63 Nd146 437.03 441.59 33.12 33.74 449.90 436.35 16.01 31.15 20.61 11.28 302.27 85.25 80.22 426.16 419.53 Sm147 457.09 459.94 34.03 34.69 472.42 458.08 16.67 20.46 13.74 11.14 65.87 47.04 42.94 445.37 437.60 Eu153 467.05 470.38 34.09 34.77 481.46 467.85 3.11 2.37 1.26 0.57 5.47 5.72 3.09 456.61 447.29 Gd157 424.96 427.26 30.97 31.72 442.95 423.77 55.93 60.59 30.37 47.57 99.13 127.08 103.63 414.97 409.30 Tb159 450.50 452.57 32.63 33.69 465.77 447.49 17.39 21.35 9.65 15.95 30.42 49.43 39.26 437.32 429.61 Dy163 432.17 434.29 30.47 31.24 448.29 431.39 185.72 243.73 108.61 179.99 332.14 608.64 475.53 421.86 414.60 Ho165 456.62 456.80 32.74 33.63 473.88 454.93 60.37 82.99 38.92 61.47 116.15 224.76 172.63 444.13 435.33 Er166 433.45 432.14 31.20 31.77 448.57 431.40 240.08 345.73 174.08 248.45 535.24 1001 771.26 421.91 412.71 Tm169 426.64 427.14 30.56 31.47 440.61 426.09 49.86 75.86 41.07 53.99 127.12 232.67 176.13 414.78 407.68 Yb172 467.60 470.13 34.61 35.65 483.53 467.86 472.56 749.92 422.88 518.15 1382 2320 1718 455.74 449.10 Lu175 441.14 443.72 31.39 32.11 457.27 441.30 71.33 108.45 69.06 70.93 265.71 321.85 256.78 429.05 420.47 Hf178 423.62 424.25 31.00 31.14 439.56 426.26 8765 10985 11227 10037 14208 15090 14976 411.91 405.53 Pb208 415.62 428.43 39.67 38.68 424.41 420.27 27.66 40.35 12.59 6.98 22.14 55.92 60.55 409.05 402.64 Th232 457.93 460.74 33.35 33.87 477.26 459.01 33.96 113.76 91.20 100.22 299.66 1076 447.58 444.03 433.23 U238 462.60 474.34 38.37 38.11 471.43 468.01 181.06 439.25 450.85 293.82 1906 3837 2005 454.34 437.64
508 Table 18 (continued): Trace element data from the Al Hawiyah Suite (hwg) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.18, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Details of this procedure are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures.
Sample Nist610g Nist610h Nist612c Nist612d Nist610i Nist610j REE8 G2 REE9 G2 REE10 G2 REE11 G2 REE12 G2 REE13 G2 REE14 G2 Nist610k Nist610l hwg07 Na23 94688 94226 100930 97094 95680 96027 58.27 187.12 696.01 55.00 128.47 44.28 120.25 94739 95256 Mg24 475.35 465.53 61.96 58.53 459.01 467.27 33.65 1062 34.97 394.60 139.81 3.74 62.77 467.04 464.38 Al27 9988 9928 9248 9528 10017 9988 93.31 2315 605.05 2599 1231 36.55 268.21 9995 10030 Si29 328329 328329 335917 335917 328329 328329 151965 151965 151965 151965 151965 151965 151965 328329 328329 P31 325.02 318.60 68.14 48.79 359.15 354.97 170.16 570.02 472.52 319.85 400.00 240.04 1487.54 349.32 328.65 K39 484.41 489.02 68.46 68.63 477.59 483.96 12.82 187.64 31.55 1167.07 94.54 8.55 26.39 483.43 491.53 Ca43 81476 79358 76894 80925 82707 81192 386.06 1570.18 1406 531.51 1600 296.54 3915 81213 82626 Ti49 420.67 434.10 32.67 36.79 416.93 423.31 7.70 49.08 24.84 52.02 50.02 11.07 15.32 436.77 441.76 Fe57 524.51 445.51 140.63 131.11 472.70 502.07 230.29 2203 438.13 867.84 429.85 68.74 372.85 442.21 449.84 Rb85 423.83 433.20 32.07 32.12 433.61 432.87 0.26 5.52 0.45 7.52 0.40 0.15 0.29 431.02 429.29 Sr88 486.87 497.11 70.23 73.40 498.75 498.98 4.38 16.04 25.19 2.31 23.26 0.13 16.92 495.78 497.75 Y89 442.52 450.17 32.12 32.95 449.64 449.42 2661 3444 6164 2127 3993 1249 2449 449.39 450.39 Zr90 429.66 441.34 28.91 28.31 435.31 439.07 514353 486647 491398 499924 538626 492790 504343 436.98 444.01 Nb93 410.17 416.73 31.89 32.75 420.84 422.75 34.19 197.18 410.74 104.39 365.41 4.85 91.57 418.00 419.18 La139 442.83 456.33 32.93 34.45 457.92 456.94 8.28 17.60 33.24 5.64 41.58 15.68 75.82 459.38 456.00 Ce140 433.61 446.17 37.35 37.25 454.11 451.14 28.68 108.96 157.56 35.35 203.29 33.53 237.77 446.03 446.14 Pr141 416.63 428.36 33.20 34.20 431.92 432.09 1.85 16.77 19.87 2.82 30.57 2.69 27.36 429.90 428.37 Nd146 419.53 430.27 31.26 32.36 431.35 428.92 9.69 99.83 105.78 17.12 168.95 13.47 153.39 432.27 430.27 Sm147 437.60 447.24 32.96 34.43 451.06 449.24 5.82 60.12 55.84 14.11 86.84 8.04 45.18 451.31 450.68 Eu153 447.29 458.28 33.01 34.35 461.35 459.86 0.75 7.15 12.81 0.94 17.76 1.71 7.96 460.93 462.28 Gd157 409.30 418.71 29.71 30.87 418.92 417.37 28.02 113.63 133.82 55.32 157.57 33.80 72.60 421.63 419.97 Tb159 429.61 441.27 31.32 32.64 442.30 440.88 13.35 38.60 48.78 20.91 49.01 11.23 20.47 444.65 442.53 Dy163 414.60 425.39 29.24 29.94 426.75 424.35 187.60 405.96 585.31 243.48 483.16 129.23 225.47 427.67 426.55 Ho165 435.33 448.32 31.73 32.92 449.24 446.95 79.52 131.14 207.63 83.52 145.68 45.08 81.97 451.00 449.43 Er166 412.71 425.13 29.68 31.01 423.57 425.60 397.75 554.21 898.78 338.28 579.46 186.20 358.77 426.95 426.52 Tm169 407.68 419.03 29.55 30.66 418.27 418.21 100.68 125.77 199.84 71.18 126.14 40.35 83.32 421.41 420.68 Yb172 449.10 459.47 33.24 34.79 460.36 460.23 1110 1276 1966 666.57 1232 394.62 865.29 462.57 461.84 Lu175 420.47 433.47 30.03 31.31 433.11 431.96 187.63 182.35 263.14 95.35 168.22 58.55 119.48 436.56 435.15 Hf178 405.53 416.49 29.01 30.87 419.06 413.22 14891 12533 13611 11596 12916 7021 11688 420.17 417.13 Pb208 402.64 416.33 38.95 37.16 417.88 412.13 22.33 136.32 148.80 13.42 118.02 2.63 33.16 412.63 412.47 Th232 433.23 448.24 31.37 32.57 449.25 449.57 366.66 500.76 836.15 163.47 335.15 49.29 350.21 454.81 448.47 U238 437.64 456.15 37.34 37.11 461.87 455.85 1745 1844 3514 491.80 734.41 76.24 1569 458.02 455.79
509 Table 19: Trace element data from the Mardabah Complex (mr) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.19, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Details of this procedure are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures.
Sample Nist610a Nist610b Nist612a Nist612b Nist610c Nist610d REE1 REE2 REE3 REE4 REE5 REE6 REE7 Nist610e Nist610f mr191 Na23 96086 98722 105736 96875 92337 98880 955.24 969.76 1109 1087 1112 1167 1081 93057 98988 Mg24 574.60 411.21 143.01 58.42 524.21 484.89 0.00 47.01 0.00 151.98 9.64 0.00 67.15 641.58 278.40 Al27 9912 10902 10760 9413 9445 9841 79.08 146.06 83.51 180.15 41.12 101.75 95.70 9887 9918 Si29 328329 328329 335917 335917 328329 328329 151965 151965 151965 151965 151965 151965 151965 328329 328329 P31 588.67 535.00 428.33 398.11 303.77 495.41 195.98 332.77 336.75 429.51 424.41 441.17 518.88 988.56 1210.48 K39 462.68 569.89 311.60 238.97 409.85 654.78 113.20 130.06 123.34 131.86 129.01 136.65 133.35 518.98 636.91 Ca43 118363 76292 118223 78071 84176 95998 9481 12303 7367 7090 10518 12981 8441 85417 78912 Ti49 552.40 309.06 0.00 0.00 573.45 304.92 17.30 51.44 28.65 53.31 0.00 0.00 25.38 369.21 500.59 Fe57 298.89 1252.70 868.42 0.00 842.60 733.63 256.66 5353.45 252.85 1516.95 239.51 331.36 214.43 426.15 741.56 Rb85 428.67 441.76 35.01 33.46 441.79 474.35 0.37 0.24 0.11 0.37 0.00 0.12 0.10 432.79 432.99 Sr88 480.32 516.19 81.38 78.61 506.19 528.31 0.22 1.78 0.00 0.72 0.00 0.00 0.77 496.59 512.02 Y89 435.73 472.26 43.61 36.68 453.40 477.04 1987 2614 1522 1217 916 1184 1282 450.39 459.41 Zr90 395.60 455.79 48.66 37.41 509.31 574.78 705715 899257 979972 1032397 1104108 1245846 1665948 83.94 229.27 Nb93 418.06 436.19 33.94 32.82 410.58 430.74 6.92 11.06 8.39 9.10 6.46 10.27 20.21 418.71 425.48 La139 538.99 523.28 36.89 29.89 391.02 410.41 0.06 1.50 0.03 1.44 0.02 0.02 0.50 459.99 459.38 Ce140 529.10 511.24 40.03 32.91 382.83 403.04 8.48 24.60 11.17 22.13 10.26 10.27 27.40 448.72 448.98 Pr141 512.53 495.75 36.83 30.25 365.05 386.40 0.40 0.89 0.26 0.80 0.15 0.16 0.25 429.65 431.58 Nd146 523.73 501.18 35.22 28.38 362.91 383.45 6.03 10.35 4.72 6.80 2.77 2.67 4.34 433.36 430.74 Sm147 546.38 528.83 36.88 29.53 378.61 400.54 10.70 13.68 8.95 7.73 5.04 5.60 7.19 449.55 451.86 Eu153 576.50 547.78 35.56 29.23 384.22 405.88 1.67 1.12 1.22 1.73 0.61 0.76 0.61 461.94 462.87 Gd157 526.40 498.72 34.27 25.85 349.23 365.79 53.34 57.13 39.05 30.86 23.13 25.35 32.28 422.22 422.74 Tb159 568.14 531.89 35.40 27.78 366.02 385.57 17.28 19.69 13.00 10.47 8.17 8.91 11.64 445.61 444.84 Dy163 556.63 519.40 32.68 26.52 350.34 371.58 185.38 229.05 142.78 115.72 90.63 106.27 134.15 428.79 428.55 Ho165 589.03 548.26 35.21 27.89 368.99 389.93 60.42 79.59 47.51 38.98 30.59 38.60 46.47 453.07 451.36 Er166 561.94 520.43 33.19 26.72 349.10 369.57 229.65 321.65 187.07 152.98 121.58 166.37 188.28 429.72 428.24 Tm169 560.92 521.88 33.07 26.44 342.81 362.21 45.45 65.15 38.61 30.43 25.05 35.54 39.11 423.14 422.22 Yb172 620.41 575.15 37.24 29.46 375.71 398.36 399.77 572.37 351.94 279.31 230.67 342.18 364.53 465.18 461.12 Lu175 584.94 541.94 34.27 26.91 353.91 373.78 56.30 79.65 49.41 38.30 32.29 50.61 49.02 439.88 435.34 Hf178 572.52 528.31 34.70 25.38 338.42 360.70 4746 9110 5703 5620 5962 5996 9815 417.12 417.96 Pb208 599.87 539.19 39.72 32.46 331.01 353.21 3.65 15.47 2.91 9.98 2.75 2.31 15.29 415.52 414.55 Th232 687.17 608.29 35.83 27.07 358.07 379.54 83.48 266.57 67.01 196.27 58.55 57.21 294.18 454.31 451.22 U238 705.46 618.97 40.65 32.34 362.61 391.43 110.17 379.51 114.20 224.57 92.21 131.87 419.37 460.89 452.79
510 Table 19 (continued): Trace element data from the Mardabah Complex (mr) zircon grains analysed by laser ablation ICPMS. The zircon ablation spots correspond to cathodoluminescence images in Appendix 3, Figure A3.19, which have already been ablated for U-Pb and Hf isotopes (Appendices 2 and 4). Nist610 is used as the calibration standard. Details of this procedure are described in Appendix a7. Values were processed using Glitter software (Van Achterbergh et al., 2001). Concentrations <1000ppm are rounded to 2 significant figures.
Sample Nist610g Nist610h Nist612c Nist612d Nist610i Nist610j REE8 REE9 REE10 REE11 REE12 REE13 REE14 Nist610k Nist610l mr191 Na23 93057 96972 103174 90642 99759 87915 2001 2293 2312 1828 1777 2371 1508 98805 93898 Mg24 641.58 549.27 64.24 60.20 581.42 597.40 20.03 0.00 94.10 0.00 19.29 24.54 0.00 618.81 343.78 Al27 9887 10291 9510 9126 10587 9498 115.91 130.24 115.02 140.25 131.17 81.80 47.87 10164 9892 Si29 328329 328329 335917 335917 328329 328329 151965 151965 151965 151965 151965 151965 151965 328329 328329 P31 988.56 1377 971.18 1592 1734 1835 1200 1616 1944 3197 2976 3613 4406 10203 11023 K39 518.98 390.50 236.08 276.53 483.87 352.93 171.53 158.68 172.39 173.52 204.35 165.75 137.91 463.57 565.91 Ca43 85417 93672 117133 66433 87078 58807 10185 2519 11080 21102 12539 10234 14738 108011 67910 Ti49 369.21 504.09 160.29 0.00 400.21 432.78 56.95 61.82 0.00 121.34 139.75 0.00 0.00 399.64 471.49 Fe57 426.15 568.89 339.08 708.77 470.95 469.01 331.71 97.37 443.28 90.52 115.68 498.62 531.42 865.31 1246.43 Rb85 432.79 444.24 35.17 26.75 443.39 401.08 0.36 0.17 0.44 0.40 0.48 0.00 0.19 444.28 428.82 Sr88 496.59 491.62 71.23 67.93 516.53 469.31 0.21 0.00 10.50 0.00 0.00 0.83 0.23 518.04 487.68 Y89 450.39 455.31 33.74 34.57 466.23 416.62 1397 1374 1236 908.43 2222 1164 1135 468.79 444.39 Zr90 83.94 750.14 37.43 16.73 639.30 561.50 784574 786055 804130 781087 857375 758251 719431 164.25 373.35 Nb93 418.71 421.97 33.87 30.67 443.57 389.81 23.04 3.33 23.40 12.21 5.33 21.43 14.14 441.74 408.38 La139 459.99 461.04 35.28 31.75 486.26 423.72 0.03 0.03 3.56 0.01 0.08 1.80 0.15 481.46 446.65 Ce140 448.72 453.59 37.92 33.95 474.26 416.82 29.21 9.25 27.91 15.79 11.43 30.82 21.57 470.93 436.58 Pr141 429.65 436.11 36.19 31.69 456.38 399.23 0.24 0.47 0.56 0.05 0.64 0.78 0.18 451.42 419.48 Nd146 433.36 433.88 33.70 29.39 457.10 402.12 3.95 6.78 4.40 1.41 10.38 6.63 3.50 454.09 418.92 Sm147 449.55 455.43 34.90 32.73 480.08 420.92 7.70 13.48 6.29 3.08 17.78 6.90 6.54 471.65 439.12 Eu153 461.94 463.96 34.76 31.02 491.47 429.86 0.54 1.67 0.81 0.33 2.50 3.39 0.49 484.97 448.82 Gd157 422.22 421.34 31.87 28.89 445.80 389.84 34.68 53.54 27.02 17.84 85.39 30.21 30.46 442.33 409.75 Tb159 445.61 445.99 33.51 31.15 467.89 411.38 12.98 16.44 10.04 7.09 26.39 10.46 11.10 466.51 432.40 Dy163 428.79 429.58 30.45 28.57 452.18 395.73 147.13 170.87 117.75 85.63 276.67 119.46 122.22 450.74 415.41 Ho165 453.07 453.18 34.29 30.43 474.54 416.08 51.42 53.47 43.29 31.78 87.38 41.79 41.77 474.78 438.89 Er166 429.72 428.52 32.04 28.70 453.79 392.39 208.87 196.85 186.01 140.09 320.44 176.77 164.08 451.05 415.71 Tm169 423.14 422.80 31.47 28.31 444.47 389.41 44.17 38.73 41.56 31.53 62.76 37.90 33.84 444.48 409.43 Yb172 465.18 464.40 34.00 31.46 491.05 429.35 408.36 341.99 403.58 301.02 546.61 367.06 304.98 487.12 449.08 Lu175 439.88 438.09 32.28 28.72 458.17 402.54 53.73 46.54 58.57 42.25 74.87 50.21 41.69 459.59 424.75 Hf178 417.12 425.17 32.00 28.67 445.64 387.85 10229 7099 11389 12190 7468 10127 8206 435.30 409.79 Pb208 415.52 418.79 37.91 33.35 440.35 380.54 10.63 2.81 44.93 6.74 5.39 9.89 7.40 435.20 404.82 Th232 454.31 453.79 33.12 30.38 477.53 418.25 239.37 61.66 161.80 151.15 120.29 183.60 162.71 473.95 440.89 U238 460.89 464.91 38.12 34.11 489.39 423.63 384.00 81.42 441.74 361.64 146.06 347.20 241.32 476.06 449.45
511