MAGMA MIXING AND EVOLUTION AT MINNA BLUFF, ANTARCTICA REVEALED BY AMPHIBOLE AND CLINOPYROXENE ANALYSES
Ellen R. Redner
A Thesis
Submitted to the Graduate College of Bowling Green State University in partial fulfillment of the requirements for the degree of
MASTER OF SCIENCE
December 2016
Committee:
Kurt Panter, Advisor
John Farver
Thom Wilch © 2016
Ellen Redner
All Rights Reserved iii
ABSTRACT
Kurt Panter, Advisor
Lava flows from Minna Bluff, Antarctica, are studied in order to provide insight into magma system dynamics, specifically magma mixing. More than 500 lava/dome and volcaniclastic samples that range in age from ~12 to 4 Ma were collected along the 45 km volcanic peninsula. Lava compositions range from basanite to phonolite. A significant proportion of lavas of all whole rock compositions contain amphibole. This study is focused on the textural and compositional characteristics of amphibole and clinopyroxene as a means to understand open system processes causing fluctuations of temperature, pressure during crystallization.
Lavas with amphibole (± clinopyroxenes) phenocrysts are texturally diverse and range from porphyritic to glomeroporphyritic. Other phenocrysts consist of olivine, plagioclase, alkali feldspars, magnetite and apatite in a groundmass that varies from holocrystalline to hypohyaline. The amphibole is mostly kaersutite and clinopyroxene is diopside. Compositional zoning in amphibole includes normal, reverse and oscillatory types. The coexisting clinopyroxene is weakly zoned. Amphiboles also exhibit weakly to strongly developed reaction rims, which are produced by decompression and/or increase in temperature.
Amphibole phenocrysts have higher Fe/Mg ratios than predicted for equilibrium conditions in basanitic magma and lower ratios than predicted for phonolitic magma. The rims of amphibole phenocrysts in intermediate compositions are mostly in equilibrium but cores of the same grain are not. Clinopyroxene phenocrysts show similar relationships. The amphibole and clinopyroxene phenocrysts that are out of equilibrium suggest magma mixing or accidental incorporation of pre-existing crystal ‘debris’. iv
Geothermobarometric results suggest that amphiboles and clinopyroxenes formed at pressures 4 to 9 kbars (≈ 15-32 km) and 3 to 14 kbars (≈ 11-47 km), respectively. The majority of barometric calculations indicate depths ≥ 22 km, which is at or below the crust- mantle boundary. It is likely that rising melt reached neutral buoyancy at this boundary and pooled, cooled and crystallized to produce more evolved compositions that were, in turn, periodically replenishment by less evolved melts from below. A five stage history is conceived that illustrates the complex nature of magma evolution at Minna Bluff.
v
To my mother,
who gave me the support and unconditional love to follow my dreams and was
always just a phone call away. Thank you for showing me that I can accomplish
anything with patience, perseverance and God’s love.
To my father,
who motivated me and showed me that I can do anything I set my mind to, and
who pushed me to do more than I thought I could. Thank you for always
answering my many questions and helping me become the strong independent
woman I am today.
To my brother,
who was always there when I needed help or support and was only a short drive
away if I needed a break. Your kindness (and cooking) helped me get though these
two years. I wouldn’t have been able to do this without you. vi
ACKNOWLEDGEMENTS
The completion of this project would not have been possible without the support and encouragement from my colleagues, friends and family.
Thank you to my advisor, Kurt Panter, for being such a terrific teacher and helping me grow as a person and geologist. I can’t thank you enough for your patience and guidance throughout this project. You have taught me more than I could have hoped for and I leave here with fantastic experiences and memories.
Thank you to my committee members, Thom Wilch (Albion College) and John Farver, I couldn’t have done this without your input and support. Thank you to Charlie Onasch for teaching me the many steps of making thin sections – I won’t soon forget! Thank you to my fellow graduate student friends, who always helped to keep me on track and focus (usually).
Thank you to the BGSU geology department in general for always being so warm and welcoming.
Lastly, thank you to Gordon Moore and Xiaofei Pu at the University of Michigan EMAL lab for the technical support. A special thank you to Xiaofei for making the long probing sessions enjoyable and for all the kindness you shared with me. vii
TABLE OF CONTENTS
Page
CHAPTER I. INTRODUCTION ...... 1
Geologic Background ...... 2
Antarctic Rifting and Volcanism ...... 3
Geology of Minna Bluff ...... 4
Xeno Ridge ...... 5
Magma Mixing ...... 7
CHAPTER II. METHODOLOGY AND ANALYTICAL TECHNIQUES...... 10
Petrography ...... 10
Mineral Chemistry ...... 11
Geothermobarometry ...... 12
Amphibole Thermobarometry ...... 13
Clinopyroxene Thermobarometry ...... 14
CHAPTER III. RESULTS ...... 15
Petrography ...... 15
Basanite and Tephrite ...... 16
Phonotephrite ...... 16
Mugearite ...... 17
Tephriphonolite ...... 17
Phonolite ...... 17
Samples with Unknown Whole Rock Compositions ...... 18
Mineral Chemistry ...... 18 viii
Amphibole ...... 19
Compositional Zoning in Amphibole ...... 20
Tschermak Substitutions ...... 21
Clinopyroxene...... 21
Mineral-Melt Equilibria ...... 22
Thermobarometry ...... 23
Amphibole ...... 24
Clinopyroxene...... 25
CHAPTER IV. DISCUSSION ...... 27
Evidence for Magma Mixing ...... 27
Disequilibrium Textures ...... 27
Disequilibrium with Whole Rock ...... 30
Crystallization Depths ...... 33
Evidence for Crystallization near the Crust-Mantle Boundary ...... 34
Minna Hook Plumbing System ...... 37
Implications ...... 39
REFERENCES ...... 41
APPENDIX A. ELECTRON ANALYSIS ...... 93
APPENDIX B. GEOTHERMOBAROMETRY ...... 156
ix
LIST OF TABLES
Table Page
1 Detailed textural and mineralogical data ...... 50
2 Empirical thermobarometric formulations for amphibole ...... 51
3 Clinopyroxene-liquid thermobarometers ...... 52
4 Summary of sample composition and petrological observations ...... 53
5 Representative amphibole c ompositions ...... 54
6 Representative clinopyroxene compositions ...... 56
7 Compositional variability within whole rock samples ...... 57
8 Transect through zoned amphiboles in sample MB07-174 ...... 58
9 Transect through zoned clinopyroxene in sample MB07-017 ...... 59
10 Summary and comparisons between whole rock compositions, temperatures, pressures,
ages, zoning and reaction rim data ...... 60 x
LIST OF FIGURES
Figure Page
1 An overview of the McMurdo Volcanic Group (MVG) ...... 61
2 Modified satellite image of the Erebus Volcanic Province (EVP) ...... 62
3 Modified satellite image of Minna Bluff ...... 63
4 Samples used in this study with locations relative to Minna Hook ...... 64
5 Total alkali silica (TAS) plots ...... 65
6 Pyroxene quadrilaterals...... 66
7 Textural classification representatives ...... 67
8 Examples of mineral inclusions within amphibole ...... 68
9 Amphibole reaction rim classification ...... 69
10 Example of zonation within amphibole and clinopyroxene ...... 70
11 TAS diagrams showing reaction rims and zonation versus composition ...... 71
12 Transect across amphibole mineral MB07-174_T ...... 72
13 Amphibole MB07-174_T transect with Ti, Mg and Fe chemistry ...... 73
14 Transect across amphibole mineral MB07-174_B-T ...... 74
15 Amphibole MB07-174_B-T transect with Ti, Mg and Fe chemistry ...... 75
16 Amphibole phenocrysts with zoning and weakly developed reaction rims ...... 76
17 Ti- and Al- Tschermak substitutions in amphibole ...... 77
18 Clinopyroxene mineral MB07-017_CC55 transect with Si, Ti, Mg and Fe
chemistry ...... 78
19 Plot of amphibole KD values versus whole rock SiO2 ...... 79
20 Plot of average amphibole and clinopyroxene KD versus whole rock SiO2 ...... 80 xi
21 Plot of clinopyroxene KD values versus whole rock SiO2 ...... 81
22 Plot of amphibole KD versus whole rock SiO2 with core and rim comparison...... 82
23 Plot of clinopyroxene KD versus whole rock SiO2 with core and rim
comparison ...... 83
24 Amphibole temperature and pressure estimates, separated into core and
rim ...... 84
25 Amphibole temperature and pressure estimates, with core and rim
comparisons focusing on whole rock composition ...... 85
26 MB07-145 core and rim comparison ...... 86
27 MB07-181 core and rim comparison ...... 87
28 Clinopyroxene temperature and pressure estimates ...... 88
29 Average pressures of formation for amphibole and clinopyroxene versus reaction rim
rating ...... 89
30 Stage I and II of the magmatic progression ...... 90
31 Stage III and IV of the magmatic progression ...... 91
32 Stage V of the magmatic progression ...... 92 1
CHAPTER I. INTRODUCTION
When two magmas meet and fuse into one product, regardless if they are from the same origin or not, is a process known as magma mixing (Lai et al., 2008). This mixing creates a new varied composition, which is an important process for magma genesis. The composition and texture of the phenocrysts from the mixed magma may provide clues about temperature and pressure conditions under which the mixing event(s) occurred, as well as provide insight into the magmatic plumbing system (Kuşcu, 2001). Magma mixing is a prominent feature of continental and island arc systems (Lai et al., 2008; Ferla and Meli 2006; Brenna et al., 2014;
Bosshard-Stadlin et al., 2014) but mixing in rift-related alkaline magmas has not been studied to the same extent (Ferla and Meli, 2006). Minna Bluff, Antarctica, is a rift-related volcanic edifice that has been comprehensively mapped, sampled, dated and has preliminary results that suggest magma mixing is an integral part of its evolutionary history (Scanlan et al., 2007; Scanlan,
2008; Dunbar et al., 2008; Panter et al., 2011). Broader studies have been done previously, such as Kyle and Cole (1974) and Wright-Grassham (1978), however this study is more specific to magma processes and builds and expands on previous research done by Scanlan et al. (2007),
Dunbar et al. (2008) and Panter et al. (2011). Although evidence for mixing has been presented in these previous studies, the role of magma mixing and the architecture of the magmatic plumbing system within the Minna Hook region of Minna Bluff are still not clearly understood.
The new data obtained are primarily focused on amphibole phenocrysts found within Minna
Bluff lavas. Amphibole provides insight to crystal formation conditions because of its stability is sensitive to changes in pressure and temperature, which can then be related to magma mixing processes and eruption dynamics (Rutherford and Hill, 1993; Ridolfi et al., 2010; Angelis et al.,
2015). 2
This study adds to the previously collected geochemical, mineral and thermobarometry data completed for 3 lavas from Xeno Ridge (Scanlan, 2008; Wilch et al., 2011) by encompassing 70 additional lavas, 23 of which provide detailed mineral chemistry on clinopyroxene and amphibole that are also used for thermobarometric calculation. Antecrysts and the role they play within the magmatic system is also discussed, so as to take in account their interaction within the system and how they may provide another avenue to explain the disequilibrium within a system. The implications of understanding the role of amphibole fractionation in alkaline magma genesis could enable a greater understanding of the behavior and causes of volcanic eruptions. An understanding the magmatic system at Minna Bluff illuminates conditions for amphibole-liquid equilibria during petrogenesis (Irving and Green,
2008), enhances the awareness of potential dangers posed for populations near volcanically active areas through an understanding of what can make volcanoes more unstable (Brenna et al.,
2014), and potentially helps with our ability to forecast eruptions (Ridolfi et al., 2010).
Geologic Background
The craton of East Antarctica first began forming in the late Neoproterozoic, during the break-up of the Rodinia supercontinent (Elliot et al., 2014). Gondwana was then formed, between 850-600 Ma, when the continental fragments of Rodinia sutured together (Condie,
2003). In the late Proterozoic to Cambrian, metamorphic rocks were intruded by Cambrian-
Ordovician granites (Stump, 1995). Following this there was a combination of uplift (from faulting and isostatic rebound) and metamorphism of sedimentary rocks in addition to the convergence of crustal material (Ross Orogeny) during the late Paleozoic and early Mesozoic
(Stump, 1995). When Gondwana broke up, about 184 Ma, Antarctica, India and Australia began to separate from Africa and South America (Enacrnación et al., 1996). This separation 3 stimulated magmatism and volcanism in the Jurassic era, which consisted largely of the Ferrar
Group (Muirhead et al., 2011). Rifting began again 95 Ma ago when Australia, Zealandia and
Antarctica separated, and has continued into the Cenozoic (Wörner, 1999). Antarctica became fully separated from New Zealand and Australia in the late Cretaceous before 84 Ma (Behrendt et al., 1991; Boger, 2011). The most recent magmatic events - 48 Ma to present (Rocchi et al.,
2002), are associated with the development of the West Antarctic rift system and include volcanism on the Marie Byrd Land dome, the Meander Intrusive Group of northern Victoria
Land and the McMurdo Volcanic Group of the western Ross Sea embayment, which is still active today (Rocchi et al., 2002; Winberry and Anandakrishnan, 2004; LeMasurier 2008). The deposits from the most recent eruptions, which formed during the Late Cenozoic, are rift- related, mostly silica-undersaturated alkaline magmas that vary from basanite to phonolite and trachyte.
Antarctic Rifting and Volcanism
The West Antarctic Rift System (WARS) encompasses the Ross Sea and Byrd
Subglacial Basins, and is bordered by the Transantarctic Mountains (TAM). The TAM separates the East Antarctic craton from the extended West Antarctica lithosphere. The WARS is magmatically active along the western margin of the rift system and is slowly separating part of the West from the East (Behrendt et al., 1991; Ritzwoller et al., 2001; Faure and Mensing,
2010). It extends over a 3000 x 750 km area of Antarctica and consists of extensional basins and substantial uplift, which formed the Transantarctic Mountains in the Cenozoic (Behrendt et al.,
1991; Fitzgerald et al., 1986; Fitzgerald, 1992). The WARS is one of the largest active continental rift systems today (Behrendt et al., 1991). Extension and rifting have caused West
Antarctica’s lithosphere to thin, thereby helping to induce volcanism within the Paleogene
4
(LeMasurier and Rex, 1989; LeMasurier W., 1990b; Behrendt et al., 1991; Huerta and Harry,
2007). Subsidence and uplift within this time period and younger rifting reaching into the
Miocene aided in creating the Terror Rift, a deep and narrow basin within the southern portion of Victoria Land (Fielding et al., 2006; Huerta and Harry, 2007; Henrys et al., 2008).
Minna Bluff is located within the Erebus Volcanic Province (EVP), which is part of the larger McMurdo Volcanic Group (MVG) (Figure 1). The MVG is a volcanic belt extending
2000 km (Kyle, 1990) with volcanic activity linked to a variety of causes including strike-slip deformation (Rocchi et al., 2002), mantle plumes (Kyle, 1990; Kyle et al., 1992) and passive decompression melting (Wörner, 1999; Rocchi et al., 2002), dating back 26 Ma and consists of silica-undersaturated alkali basalts (Wörner, 1999; Kyle, 1990; Martin et al., 2014). EVP is located within southern Victoria Land in the McMurdo Sound region (Figure 2) and is the main volcanically active area today (Martin et al., 2014) depositing compositions ranging from basanite to phonolite and trachyte (LeMasurier, 1990b).
Geology of Minna Bluff
Minna Bluff, originally an island, grew into a 45 km long peninsula (Figure 2) through continual volcanic activity (Wilch et al., 2011). This peninsula is composed of two segments; a
~25 km SE-oriented ridge that includes the southwest-facing McIntosh Cliffs (Wilch et al.,
2011) and a ~20 km north-south oriented ridge called Minna Hook (Wright-Grassham, 1987;
Wilch et al., 2011). Minna Hook’s elevation reaches over 1,100 meters asl while the rest of the
Minna Bluff decreases in elevation (with the bluff top averaging ~800 meters asl. The deposits at Minna Bluff have been dated by the 40Ar/39Ar method and range from 12 to 4 Ma (Ross,
2014). Over that period of time the volcanism migrated to the northwest and the furthest extent of Minna Bluff may now underlie the younger Mt. Discovery edifice (Scanlan, 2008; Antibus et 5 al., 2014). Minna Bluff has a complex history documented by over 200 eruptive episodes
(Antibus et al., 2014) extending from the Minna Hook in the southeastern part of the peninsula to Mt. Discovery in the northwestern part of the peninsula (Wilch et al., 2011; Antibus et al.,
2014; Ross, 2014). Minna Hook has an age range of 12-8 Ma and deposits consist mostly of lava, domes, autoclastic and hyaloclastic breccia, along with minor pyroclastic deposits
(Scanlan, 2008; Wilch et al., 2011; Ross, 2014). Also documented are rare epiclastic sediments found interbedded with primary volcanic sequences and subaqueous deposits such as quenched pillow/lobe shaped lavas (Scanlan, 2008; Wilch et al., 2011; Antibus et al., 2014). Subaerial deposits consist of tephra, tabular ‘a’ā lava, autobreccias (Wilch et al., 2011) and monogenetic cones that are well preserved along the top of the Minna Bluff peninsula (Scanlan, 2008). The occurrence of pillow/lobe-shaped lava is noted to have formed through the interaction with glacial meltwater (Wilch et al., 2011; Antibus et al., 2014). Wilch et al. (2011) hypothesized this to be due to the eruptions occurring just beneath a thin ice layer. The compositions of the volcanic rocks show a full range of alkaline types from basanite to phonolite that are undersaturated with respect to silica (Scanlan, 2008; Panter et al., 2011). The range in compositions found at Minna Bluff are comparable to the range of compositions found at Mt.
Erebus (Kyle et al., 1992; Esser et al., 2004) ~100 km to the north (Figure 2).
The ridge along McIntosh Cliffs, active 8-4 Ma, has mostly subaerially emplaced basanite deposits consisting of tabular ‘a’ā lava with associated red autobreccias in addition to more than 50 partially eroded domes and cinder cones that contain interbedded scoria lapilli and agglutinated spatter (Scanlan, 2008; Wilch et al., 2011; Antibus et al., 2014).
Xeno Ridge
The most recent study on the petrology of Minna Bluff was for a Master’s thesis
6
(Scanlan, 2008). Scanlan (2008) focused on characterizing three inclusion-rich lavas and a dome found in one area at Minna Bluff (‘Xeno Ridge’) to determine inclusion and magma origins, magma differentiation and eruption dynamics. Xeno Ridge lies at the top of Minna
Hook (Figure 3) with deposits that extend ~1 km in length in a NE-SW direction. The lavas that comprise Xeno Ridge are dark to light gray in color and contain fluidal shaped, highly vesicular inclusions that indicate magma comingling. The lavas also contain a variety of inclusions with sharp contacts indicating that they were incorporated in lava in the solid state (Scanlan, 2008).
At the southwestern end of Xeno Ridge there is a yellow volcanic breccia which contains clasts of lava bombs, flow banded dome lava in addition to inclusion-bearing lava fragments. Five main types of inclusions were identified within the Xeno Ridge samples and described by
Scanlan (2008). Of the five inclusions identified, three were analyzed for whole rock compositions, giving a compositional range from phonotephrite to trachyte and contain phenocrysts of feldspar, clinopyroxene, magnetite and amphibole (–kaersutite). Kaersutite is a titaniferous amphibole (NaCa2(Mg4Ti)Si6Al2O23(OH)) that falls within the calcic amphibole category (Leake et al., 1997). Scanlan (2008) analyzed amphibole and clinopyroxene for mineral chemistry in order to derive temperatures and pressure of crystallization using the geothermobarometric methods of Ernst and Liu (1998), Nimis and Ulmer (1998) and Nimis
(1999). The results indicate that the crystallization of kaersutite and clinopyroxene mostly occurred between 5 and 9 kbars pressure, which is equivalent to 15 to 27 km depth (calculated assuming a middle crust to upper mantle density of 2.9 to 3.3 gm/cm3). Combining the data with field relationships and inclusion data, Scanlan proposed a four stage magma system evolution:
Stage I: phonolitic magmas (the host of the inclusions) ascended to the upper crust, Stage II: replenishing phonotephritic magmas (fluidal type I inclusions) rose within the same conduit 7 system, Stage III: these two magmas mixed and rose higher, Stage IV: the quick ascent of magmas, entraining in their solid state inclusions from the conduit walls during eruption.
Magma Mixing
Expanding of the work of Scanlan (2008), this study encompasses a larger area of Minna
Bluff (i.e. Minna Hook), allowing the evolution of magma mixing on a greater scale.
Understanding the controls on magma mixing, ascent rate and eruptive conditions of a magma are linked to knowing the physical and chemical properties of a melt. Magmatic minerals can record pre-eruptive processes within a volcanic plumbing system, which can then be used to infer conditions under which that mineral formed. Textural and mineralogical changes recorded within a mineral can aid in determining magma supply/replenishment fluctuations within the system, which provide evidence for magma mixing.
There are two physical aspects of magma mixing that have been outlined by Sakuyama
(1984); mechanical mixing and molecular diffusion. Mechanical mixing is controlled by the
Reynolds number of the magma, which is a ratio of inertial forces to viscous forces, and the duration of the flow. Molecular diffusion on the other hand, temperature and time dependent, changes the composition through diffusing chemical species. These two processes lead to homogenization of the magma and therefore can make it difficult to identify the individual magmas involved in the mixing event (Anderson, 1976).
Magma mixing is thought to help stimulate the ascent and eventual eruption of magma
(De Angelis et al., 2015). The reheating and change in dynamics of the system can help stimulate magmatic processes (e.g. crystallization, dissolution, vesiculation, assimilation). These changes are documented as disequilibrium textures in minerals (e.g. reverse or oscillatory compositional zoning, mineral resorption, reaction rims and coronas) caused by the interaction 8 of magmas that are compositionally and/or thermally disparate (Anderson, 1976; Sakuyama,
1984; Rutherford and Devine, 2003; Marzoli et al., 2015). Amphibole can provide evidence for magma mixing due to its sensitivity to changes in temperature, pressure and water content of the magma system it is within (De Angelis et al., 2015). As a hydrous mineral, amphibole becomes unstable with changes in temperature and/or pressure. Amphiboles, stable at high pressures, will release volatiles when ascending and begin to breakdown, due to the degassing of the surrounding melt. This pressure release, and then dehydration, over a given period of time forms a “reaction rim” on the amphibole crystal (Browne and Gardner, 2006; Ridolfi et al., 2010).
Reaction rims can also form in response to changes caused by interaction of its host magma with another magma or surrounding country rock (Best and Christansen, 2001; Streck, 2008).
The reaction takes place along the edges of amphibole grains, when the crystal is out of equilibrium, and moves inward with time, with thicker sample rims indicating longer time periods for diffusion or increase in diffusion (kinetics) caused by fluids and/or higher temperatures (Rutherford and Hill, 1993; Rutherford and Gardner, 1998; De Angelis et al.,
2015). Multiple reaction rim layers indicate multiple periods of disequilibrium and reaction
(Browne and Gardner, 2006). It has been found that magmatic systems that exist at low pressures <10 MPa have too high of a melt viscosity for reaction rims to form (Browne and
Gardner, 2006). If at higher pressures the ascent is slow enough, then reaction can completely replace the mineral, leaving pseudomorphs or “ghost amphiboles” (Scott, 2013; De Angelis et al., 2015). These remnants may retain the crystal shape of the amphibole but have completely reacted to form other minerals, mostly magnetite, clinopyroxene and plagioclase.
Heating is an important factor in forming reaction rims on amphibole during magma mixing. While there are many studies that have assessed decompression to derive magma ascent 9 rates based on reaction rim thickness on amphibole (Rutherford and Hill, 1993; Browne et al.,
2003; De Angelis et al., 2015), very few studies have been done analyzing heating alone in the formation of reaction rims. De Angelis et al. (2015) experimentally determined that reaction rims formed from heating alone are texturally consistent with ones formed from decompression, making it hard to differentiate between these mechanisms. Heating and reheating can compositionally zone amphibole crystals, through the rechargment of the magma chamber, in addition to creating complex reaction rim textures (Andrew et al., 2008). Therefore temperature and pressure changes, acting in unison, can cause disequilibrium textures in amphibole (Stewart and Fowler, 2001; Rutherford and Devine, 2003; Buckley, 2006; Humphreys et al., 2006).
Magma mixing at Minna Bluff has been documented in a few lavas at Xeno Ridge by the physical evidence in outcrop (fluidal inclusions in lava) but also by evidence gathered from minerals, particularly reaction rims and reverse compositional zoning in amphibole (Scanlan,
2008). However, in this study I will examine lavas from a much broader area, quantifying and detailing textures in amphibole, and then using the information in conjunction with mineralogical data to support magma mixing. 10
CHAPTER II. METHODOLOGY AND ANALYTICAL TECHNIQUES
A total of 579 samples were collected during the 2006-2007 & 2007-2008 expeditions consisting of sediment, lava, dike/sill, hyaloclastite and tephra within the Minna Bluff region
(Figure 4) (Scanlan, 2008; Wilch et al., 2011; Panter et al., 2011). Of these samples, 186 have whole rock chemistry (Figure 5a). Seventy of those contain amphibole phenocrysts found in lavas, of which twenty-three units (Table 1), including one without amphibole, were examined in this study. These units were lavas, dikes and spatter-feed lavas. Of these, nineteen were probed for mineral chemistry (Figure 5) with 3 of the nineteen previously analyzed by Scanlan
(2008). Thin sections of units found in the Minna Hook region of Minna Bluff (Figures 3 and 5) were analyzed through standard petrographic microscope techniques. The best representative samples were selected for microprobe analysis. Mineral chemistry provides data for classification, assessment of mineral zoning and thermobarometric calculations. Pressure and temperature estimates for clinopyroxene and amphibole were calculated based on the models from Putirka et al. (2003) and Ridolfi et al. (2010), respectively. This data aided in interpreting the magmatic evolution and crystallization sequences within the Minna Hook area.
Petrography
A total of 23 samples of thin and thick sections from the Minna Bluff area were analyzed using an optical microscope to estimate volume percent vesicles, vesicle and general textures, identify types of phenocrysts, percent amphibole, crystal orientation, inclusions in amphibole, identify mineral zoning and measure amphibole rims (Table 1). These samples resent 18 different lava units, collected from a wide number of localities on Minna Hook (Figure 4), and were chosen for this study based on the amount of amphibole, the diversity of reaction rim development (Table 1) and the diversity of whole rock compositions (Figure 4b). A total of 16 11 of the 23 samples were analyzed in this study for mineral chemistry. Three others were previously analyzed by Scanlan (2008).
Mineral Chemistry
Electron microprobe analyses were conducted at the University of Michigan using a
Cameca SX-100 Electron Microprobe Analyzer with the assistance of Gordon Moore and
Xiaofei Pu to obtain chemical compositions of amphibole and clinopyroxene from the selected
Minna Bluff samples. The Cameca SX-100 is equipped with five vertical wavelength-dispersive spectrometers, backscattered electron and absorbed current imaging in addition to transmitted and reflected light imaging. A beam current of 20 nA was used during analysis with a 20-second counting time for all elements. The electron microprobe has a detection limit of ~0.2 wt. % with an analytical uncertainty of < 1.0 % and trace element uncertainty of < 10 %. A total of 246 spot analyses were collected on phenocrysts in 19 samples with 12 of the spots deemed unacceptable due to poor measurement quality from misaligned beam placement. The analyses include multi- spot core to rim transects on three phenocrysts (2 amphibole and 1 clinopyroxene). These points provided compositional information used to identify any variations throughout the minerals.
While amphibole reaction rims and zoning can differ throughout the same grain, transects enabled the ability to see finer scale variations in composition.
Amphibole was analyzed for the major element oxides SiO2, Al2O3, FeO, MgO, CaO,
Na2O and K2O and minor element oxides MnO and TiO2. Major elements are used to classify the amphibole variety and also provide information on the extent of magma evolution.
Amphiboles are classified using an excel spreadsheet (AMPH-CLASS) from Esawi (2004), which is based on the International Mineralogical Association recommendations from Leake et al. (1997), for the classification and nomenclature of amphiboles. Minor elements commonly 12 substitute for major elements within the amphibole crystal lattice (Hawthorne, 2007). The trace element F was also measured and commonly substitutes for hydroxyl (OH) in the amphibole structure (Petersen et al., 1982). Magnesium and Fe contents are used to determine state of evolution (i.e. how mafic it is), while Ca, Na and K were used to identify formation conditions.
Sodium and K specifically impact substitution among magnesium, iron and manganese. The silica content is used to identify how evolved a magma is in addition to aiding in geothermobarometric techniques. Aluminum oxide (Al2O3) TiO2, MnO concentrations were used for geothermobarometry as well.
For clinopyroxene, element oxides analyzed are SiO2, Al2O3, MgO, CaO, TiO2, Na2O,
FeO, and MgO. Clinopyroxene was classified using the pyroxene quadrilateral diagram (Figure
6). Clinopyroxene chemistry can be used to estimate crystallization pressure and temperature at which it grew (Putirka et al., 2003; Putirka 2008). Substitutions through Na, Al, Mg, Fe and Si can yield information on the minerals formation conditions. Calcium is also useful to analyze as variations can indicate differences in temperatures (Adam and Green, 1994).
Geothermobarometry
Mineral compositions of amphibole and clinopyroxene are used to estimate equilibrium temperature and pressure conditions. Estimates of temperature and pressure were done using (1) quantitative thermobarometric calculations; and (2) qualitative evaluation of pressure and temperature using Al- and Ti- Tschermak substitutions. Al-Tschermak substitution (TSi + M1-
M3Mg = TAl + M1-M3Al) and Ti-Tschermak substitution (TSi + M1-M3Mn = TAl + M1-M3Ti) reflect coupled exchanges of atoms with different ionic radii into different structural sites and is controlled by changes in temperature and pressure (Spear, 1981; Schmidt, 1992; Anderson and
Smith, 1995; Bachman and Dungan, 2002). 13
Amphibole Thermobarometry
Empirical thermobarometric formulations from Ridolfi et al. (2010) use amphibole minerals chemical composition to calculate the conditions of amphibole crystallization (Table
2). An Excel spreadsheet (AMP-TB.xls) was available to calculate the physical-chemical amphibole conditions (Ridolfi et al., 2010). Amphiboles where the formulas are not charge balanced or contain BCa < 1.5 are not classified. The temperature formula has a +22°C max error, while the pressure index in the melt has uncertainties ranging from <11-24%, based on the minerals stability relative to whole rock composition. The H2Omelt has an error up to 15%
(Ridolfi et al., 2010). These equations are based on multivariate least-square analyses of experimental amphibole compositions and physico-chemical parameters, which link amphibole compositions and physical-chemical conditions (Ridolfi et al., 2010; 2012).
The most abundant calcic amphiboles within the Minna Bluff lavas, fluoro-kaersutite and kaersutite, have high Ti and Al contents with low H2O concentrations. These attributes allow temperature and pressure conditions to be analyzed using Ti- (pressure sensitive) and Al-
(temperature sensitive) Tschermak substitution (Spear, 1981; Schmidt, 1992). The Ti-
Tschermak substitution involves substituting smaller atoms with atoms having larger ionic radii:
Si to Ti and Mn to Ti at high temperatures, because these are most sensitive to temperature changes. Si to Ti substitution is within a tetrahedral site and the charge deficiency is taken care of by exchangeable cations located between amphiboles sheet structure (White, 2013).
Manganese to Ti substitution is within an octahedral site, the charge deficiency is taken care of by exchangeable cations (White, 2013). The Al-Tschermak (TSi + M1-M3Mg = TAl + M1-M1Al) involves substituting larger atoms with atoms having a smaller ionic radii such as: Si to Al and
Mg to Al because these are most sensitive to changes in pressure (Schmidt, 1992). Mg to Al 14 substitution is within an octahedral site, the charge deficiency is taken care of by exchangeable cations (White, 2013).
Clinopyroxene Thermobarometry
The thermobarometry of clinopyroxene formation is based on jadeite (Jdcpx) crystallization and jadeite-diopside + hedenbergite exchange equilibria (Putirka et al., 2003).
The equations used for clinopyroxene thermobarometry are listed in Table 3. Within these equations, Jdcpx is the mole fraction of jadeite in clinopyroxene with pyroxene cations being calculated using 6 O atoms. Jd equals the lesser of Na or VIAl; with any Al remaining being used to form Ca-Tschermak (=VIAl-Jd). Error for the barometer is 1.7 kbar and standard estimated error for the thermometer is 33 K (Putirka et al., 2003). 15
CHAPTER III. RESULTS
Petrography
The results from petrography and mineral chemistry of amphibole and clinopyroxene are discussed in the context of the whole-rock compositions of their host lava, from mafic to felsic.
The whole-rock chemistry of Minna Bluff (Figure 5a) is provided by Scanlan (2008) along with some mineral chemistry from several lavas at Xeno Ridge. Overall textures and mineralogy details are given in Table 1 and representative images are given for textures (Figure 7), inclusions within amphibole (Figure 8), amphibole reaction rims (Figure 9) and zonation
(Figure 10).
Four samples were not analyzed for whole rock chemistry, but are here given a general classification based on the mineral assemblage and mineral chemistry, which are used in comparison to samples with known compositions. By this method, samples MB07-185A2,
MB07-180C and MB07-181 are considered to be tephriphonolitic. With only petrography on sample MB07-010, it is roughly inferred to be basanite. These classifications will be later used with the rest of the samples to support interpretations.
Reaction rims on amphibole phenocrysts are ranked 1-3 based on the relative development (i.e. the thickness) of the reaction rims. The reaction rims were measured in micrometers using a calibrated scale (Figure 9). Amphiboles that receive a ‘1’ rating consist of those having average reaction rims between 0 and 19 microns (μm) in thickness and are termed as weakly developed. Amphiboles that receive a ‘2’ rating are those with reaction rims that range between 20 and 40 μm in thickness and are classified as moderately developed. The amphiboles that have average reaction rims of 41-80 μm are ranked as a ‘3’ and classified as strongly developed. Amphiboles in which the reaction had progressed all the way through the 16 mineral are classified as ghost amphiboles and are not included when calculating the total percent amphibole within a sample. In addition optically identified zoning within amphibole and clinopyroxene is documented as well (Table 4). There is no association between reaction rim type and whole rock composition (Figure 11a) but it does appear that zoning in amphibole is predominantly within intermediate to more evolved compositions (Figure 11b). Furthermore, sample data suggest that older samples have more developed reaction rims (Table 10).
Basanite and Tephrite
Samples classified as basanites (n=3) and tephrites (n=2) range from hypohyaline to holocrystalline, are porphyritic and glomeroporphyritic and often show pilotaxitic textures.
Sample vesicularity varies from a 5 to 15%. Major phenocrysts are clinopyroxene, plagioclase, olivine and amphibole, totaling 15 vol. %, with amphibole making up 4-10%. Inclusions within
Sample MB07-017 provided plagioclase and magnetite inclusions within amphibole, while clinopyroxene had plagioclase inclusions within sample MB07-141. A few amphibole ghosts were noted within the samples and are composed of fine-grained magnetite, clinopyroxene and plagioclase. One tephrite contains amphibole that has strongly developed reaction rims (“3”) and optically identifiable zoning in clinopyroxene but not amphibole. The other tephrite
(MB07-009) shows moderately developed reaction rims on amphibole but the phenocrysts are not zoned.
Phonotephrite
Two samples are classified as phonotephrites and both have hypocrystalline, porphyritic and trachytic textures. Vesicularity varied as one of the samples (MB07-145) contains no vesicles, while the other sample (MB07-180A) has 8 vol. % vesicles (Table 1). Phenocrysts found within the samples consist of plagioclase, amphibole, clinopyroxene and magnetite, 17 totaling 10-15 vol. %. Amphibole phenocrysts comprised ~ 7 vol. % and sample MB07-145 contained plagioclase inclusions. Amphibole in both samples show zoning and strongly developed reaction rims. Also in this sample ‘ghost amphiboles’ make up 5 vol. %.
Mugearite
Only one sample is categorized as mugearite; MB07-028 (Table 1). This sample shows hypocrystalline, porphyritic and pilotaxitic textures with very few vesicles. Phenocrysts found within this sample are plagioclase, amphibole and magnetite (totaling 15 vol. %), with plagioclase and apatite inclusions within amphibole. Amphibole phenocrysts make up ~4 vol. % of the sample and have strongly developed reaction rims. Zoning occurs within both amphibole and clinopyroxene minerals.
Tephriphonolite
Samples with this composition (n=5) show hypocrystalline, porphyritic and trachytic textures in most samples and vesicularity that ranges from 2 to 40 vol. %. Phenocrysts consist of plagioclase, amphibole, magnetite and clinopyroxene (totaling an average of 30 vol. %), with sample MS-114 also containing anorthoclase (Table 1). Amphibole phenocrysts average 10 vol.
% commonly contained plagioclase inclusions. The majority of the amphibole in these samples have moderately developed reaction rims (type 2, Table 4) and are zoned. However, there is some variability in reaction rims with amphibole in sample MS-114 being weakly developed and amphibole in sample MB07-174 being strongly developed. Ghost amphiboles were observed in all tephriphonolite examined and commonly makes up 5 vol. % of the sample.
Clinopyroxenes within these samples are weakly zoned.
Phonolite
Samples that are phonolite (n=5) display hypohyaline, porphyritic and trachytic textures 18 with groundmasses that vary from holocrystalline to hypocrystalline. One sample (MB07-114) exhibits a microphenocryst holocrystalline texture (Figure 7B). The samples have predominantly low amounts of vesicles (mostly <10%). Phenocrysts consist of anorthoclase, plagioclase, amphibole, magnetite and sparse clinopyroxene (totaling 20 vol. %) with amphibole comprising ≤10%. Sample MB07-114 was noted having plagioclase inclusions. Reactions rims on amphibole range from weak to strong and there are a few ‘ghost amphiboles’. Several amphiboles exhibit zoning with zoning in clinopyroxene microphenocrysts also noted within sample MB06-827.
Samples with Unknown Whole Rock Compositions
The majority of the samples show hypocrystalline and porphyritic trachytic textures but holocrystalline and pilotaxitic textures are also present (estimated whole rock composition is labeled in italics in Table 1). Vesicularity is highly variable, ranging from 10 to 50%.
Phenocrysts are amphibole, plagioclase, olivine, clinopyroxene and magnetite (45 vol. %) with amphibole contents ranging from 10 to 50 vol. %. The amphiboles contain few inclusions of plagioclase. Amphibole in MB07-180C and -181 show weakly developed reactions rims and zoning, while the other half display strongly developed reaction rims but without zoning.
Amphibole ghosts were only found within one sample, MB07-185A2.
Mineral Chemistry
Mineral chemistry for olivine, clinopyroxene, feldspars and amphibole was previously obtained for samples MS-113, MS-114 and MS-169 collected at Xeno Ridge (Scanlan, 2008).
New chemical data specifically on amphibole and clinopyroxene was generated for 17 additional samples (MB07-185A2, 184, 181, 180C, 174, 167, 145, 141, 134, 114, 028, 025, 017,
010, MB06-832, MB06-827 and MB06-508) from the Minna Hook region of Minna Bluff 19
(Figure 4). The results are used to classify the minerals and to evaluate compositional variability between minerals (inter- and intra-sample) and compositional zoning within individual crystals.
In addition, mineral chemistry is used to calculate temperature and pressure of crystallization using geothermobarometric methods. Furthermore, experimentally determined Fe-Mg exchange coefficients are used to evaluate whether or not the amphibole and clinopyroxene grew in chemical equilibrium with its host magma. Representative compositions for amphibole and clinopyroxene are given in Tables 5 and 6. A complete set of results is provided in Appendix A.
Amphibole
All (n = 234) amphibole analyses are classified as calcic amphiboles (kaersutite, ferrokaersutite, ferropargasite, mangesiohastingsite, ferroedenite, magnesiosadanagaite). The
2+ 3+ calcic endmembers (An(Ca2)(Z 5-mZ m)(Si8-(n+m)Al(n+m))(OH,F,Cl)2) are defined as monoclinic amphiboles in which; (Ca + Na)B > 1.00; NaB < 0.50; and CaB is usually > 1.50 (Leake et al.,
1997). Modifiers to the root names were determined when a mineral is enriched in specific elements (e.g., Titano = Ti > 0.50, Potassic = K > 0.50, etc.) and indicate a compositional variant (Table 7).
All amphibole compositions from this study and those of Scanlan (2008) are presented in plots typically reserved for the classification of pyroxene (‘pyroxene quadrilateral’ after
Morimoto et al., 1988) that describe Ca (wollastinite – Wo), Mg (enstatite - En) and Fe
(Ferrosillite - Fs) Figure 6. The top diagram (6a) presents data collected in this study, Figure 6b is data collected previously (Scanlan, 2008) and Figure 6c and 6d are the same points separated into analyses from rim and core (Scanlan, 2008).
The compositional range of amphibole measured in this study generally matches what has been previously measured by Scanlan (2008) from Xeno Ridge but show a slightly wider
20 range towards both more Mg-rich and Fe-rich ends (Figure 6a and 6b). The whole rock compositions from the three lavas from Xeno Ridge are restricted to phonolite and tephriphonolite, accounting from its smaller range. Amphibole and clinopyroxene phenocrysts examined in this study are from lavas that encompass the entire range of alkaline compositions.
Within mafic whole rock compositions (basanite, tephrite and mugearite) the amphiboles show the least compositional heterogeneity; kaersutite and fluoro-kaersutite (Table 7). The greatest range in amphibole compositions occur in tephriphonolites (16 identified compositional varieties) and phonolites (13 varieties). The more felsic compositions are dominated by ferri- kaersutite and fluoro-kaersutite varieties (Table 7).
Compositional Zoning in Amphibole
Petrographic observations reveal that zoning is prevalent in both clinopyroxene and amphibole (Figure 11) and over most of the range of whole rock compositions (Figure 6b).
Compositionally, microprobe analysis reveals both reverse and normal zoning in amphibole. To detail compositional changes with zoning, two transects of euhedral, strongly zoned, amphibole phenocrysts from a tephriphonolite lava (MB07-174) were performed (Table 8; Figures 12-15).
In general, core-rim transects show, overall, normal zonation, with decreasing Mg, Si and increasing Fe concentrations towards the rim. Titanium is more variable but shows overall decreasing values rim-ward (Table 8; Figures 13 and 15). However, concentrations vary in a broad oscillatory fashion. For example, Ti and Mg both show higher concentration near the core in grain “T” of sample MB07-174 but then steadily decrease in concentration towards the rim
(Figure 13). Iron concentrations across the same transect have a complimentary but opposite trend relative to Ti and Mg (Figure 13). Another amphibole phenocryst in the same sample (“B-
T”) was analyzed and roughly exhibits the same compositional zonation (Table 8; Figures 14 21 and 15), although this phenocryst lacks the pronounced decrease in Fe and increase in Mg and
Ti near the core as exhibited in the other phenocryst “T” (Figure 13). It is of interest to note that the reaction rim on the amphibole phenocryst “T” (Figure 12) is much less developed relative to phenocryst “B-T” (Figure 14). As a whole, the zoned amphibole phenocrysts in this sample
(MB07-174) contain a diversity of reaction rim types (i.e. moderately to strongly developed) but other samples show strongly zoned amphibole phenocrysts with weakly developed reaction rims
(Figure 16).
Tschermak Substitutions
Temperature and pressure conditions analyzed using Ti- (pressure sensitive) Tschermak substitution (Spear, 1981; Schmidt, 1992) yielded weak correlations with atomic substitutions, indicating that pressure did not have much control over amphibole formation (Figure 17).
However, Al- (temperature sensitive) substitutions (Spear, 1981; Schmidt, 1992) indicated a very strong correlation with changes in temperature (Figure 17), suggesting temperature was an important factor during amphibole crystallization.
Clinopyroxene
Clinopyroxene data were collected from seven samples (MB07-141, -167, -017, -145, -
028, -114 and MB06-827). Regardless of their whole rock composition, the vast majority of clinopyroxene (n = 172) is diopside with only a few analyses that classify as hedenbergite
(Figure 6). Representative analyses are presented in Table 6. Compositional zoning was also documented optically for phenocrysts within five samples. Of these, one diopside (MB07-
017_CC55T) within sample MB07-017 was analyzed in a 14 point transect and shows only subtle variations (Table 9 and Figure 18). The most significant variations are in Si and Ti that show higher and lower values, respectively in the core relative to rims. Within this sample Ca 22 increases and then decreases in content from core to rim, indicating that the rim originally crystallized at lower temperatures, but then increased at higher temperatures (Adam and Green,
1994). Comparing core and rim data without a transect yields core and rim commonly within
~0.1, failing to aid understanding the crystallization temperatures during clinopyroxene formation.
Mineral-Melt Equilibria
Mineral-melt equilibrium is assessed using the Fe-Mg exchange coefficients (KD =
amph amph liq liq (x FeOt/x MgO)/( x FeOt/x MgO) determined for amphibole (0.28 ±0.11, Putirka, 2016) and clinopyroxene (0.27 ±0.03, Putirka, 2008). The amphibole exchange coefficient is independent of pressure or temperature and is based on 23 oxygen atoms per formula unit. The Mg-Fe exchange can be affected by Na-Al exchange and can cause slight errors, which may alter the equilibrium and may cause slight error while using this method. Values too far outside of equilibrium (>0.5) are excluded from Putirka’s study (2016) but are kept in this study.
Clinopyroxene exchange coefficient similarly does not take into account Na-Al or Ca-Na exchange, which may skew the results. The acceptable range of values using this method ranges from 0.04 to 0.68.
The majority of amphiboles found in phonolite and tephriphonolite compositions (SiO2 wt. % 52-58; phonotephrite-tephriphonolite) fall within, or moderately peripheral, to the equilibrium envelope shown in Figure 19. In general, the more mafic samples (basanite, tephrite and phonotephrite, SiO2 wt. % 45-50) have a greater proportion of amphibole that lie outside of the equilibrium envelope (Figure 19). Additionally, an average KD calculated for all amphibole analyses shows an overall decrease with increasing SiO2 of the whole rock (Figure
19). 23
The KD of some clinopyroxene-whole rock pairs are fairly tightly constrained and consistent with being in equilibrium while others are clearly in disequilibrium (Figure 21).
There is a very weak negative correlation of averaged KD calculation with SiO2 content of whole rock (open symbols in Figure 20). MS-169 and MS-114 display a wide range of KD (0.1 to 0.8). Clinopyroxene in sample MB07-141 all plot far outside of equilibrium (at least ~0.1).
In Figures 22 and 23 cores and rims for amphibole and clinopyroxene are shown for each sample. Amphibole cores are more consistently outside of the envelope of equilibrium relative to the rims in Figure 22, especially between amphiboles within the SiO2 range of 48-54 wt. % (phonotephrite to tephriphonolite). This data could be slightly skewed due to there being more acceptable amphibole core data points than rims. Clinopyroxene data exhibits a lack in correlation or trend when comparing core and rim values. Overall there is a weak correlation with clinopyroxene rims favoring lower KD’s than their accompanying cores.
Thermobarometry
A total of 486 analyses from amphibole and clinopyroxene were evaluated for thermobarometry following the methods of Ridolfi et al. (2010) and Putirka et al. (2003). Of these, 184 amphibole analyses and 172 clinopyroxene analyses yielded acceptable results. The rest of the points (n = 130) did not fit the requirements of the thermobarometers used and therefore were discarded. For amphibole, points discarded were those within the spreadsheet that did not charge balance or have recalculated total oxides > 98 wt. % (Ridolfi et al., 2010).
Additionally, physical-chemical conditions provided invalid results if a species had low calcium
(BCa < 1.5) (Ridolfi et al., 2010). For clinopyroxenes, samples that did not fit the requirements lacked Na2O and K2O data. Analyses that yield negative temperature and pressure values were 24 also discarded. The final, reliable, results are summarized in Table 10. See Appendix B for further details on each mineral probed.
Amphibole
The temperatures estimated for the formation of amphibole range from 1006°C to
1118°C, with pressures ranging from 4.1 to 9.4 kbar (17 to 34 km depth assuming an average continental crustal density of 2.8 g/cm3) (Figure 24). Temperatures of cores and rims are indistinguishable within error of the calculation. The majority of the pressure calculations for amphibole (87%) are between 5 and 9 kbar with only a few data points at higher pressures
(Figures 24 & 25). More analyses lie at pressures of less than 5 kbar but none are less than 4 kbar (~17 km equivalent depth). Compositionally, tephriphonolites had the largest range of temperatures (1006-1109ºC) and pressures (4.4-9.2 kbar) while tephrite had the tightest range of formation temperatures and basanite had the smallest range of formation pressures. It is important to note that the larger data set for tephriphonolites may skew this observation.
Amphiboles show an overall increasing temperature of formation with increasing pressure, but whole rock compositional types do not progress as one would expect with higher temperature and pressures; i.e. tephriphonolite compositions alone encompass the entire P-T range calculated from amphibole (Figure 25). This could be due to mixing event(s) or amphiboles lack in sensitivity when used as a thermometer.
For the majority of samples P-T estimates between core and rim do not show any systematic variation. However, amphibole in sample MB07-145 shows rims that formed at higher pressures and temperatures than their corresponding core (Figure 26). Applying Ti-
(pressure sensitive) and Al- (temperature sensitive) Tschermak substitutions is also shown on
Figure 26. Sample MB07-181 shows a similar trend but is not as statically significant (Figure 25
27). Both of these samples have Al-Tschermak substitutions indicating temperature being heavily correlated with formation, while Ti-substitutions yielded no such trend (Figure 26 and
27). There are no correlations between pressure or temperature and reaction rim thickness or
‘strength’ of zoning.
Clinopyroxene
Clinopyroxene phenocrysts have a larger range of calculated temperatures and pressures for formation than the amphiboles. Temperatures range from 859° to 1270°C and pressures range from 2.9 to 13.9 kbar, which is equivalent to 11 to 51 km depth (at 2.8 g/cm3) (Figure 28).
Clinopyroxene formation temperatures in phonolite range 859-952°C, tephriphonolite 959-
1050°C, mugearite 1037-1045°C, phonotephrite 1052-1057°C and tephrite and basanite range from 1066-1270°C. As would be expected, higher formation temperatures correlate with more mafic whole rock compositions, which was not the case for amphibole. The clinopyroxene P-T data also correlate with amphibole reaction rims. That is higher pressures and temperatures calculated for clinopyroxene are associated with more strongly developed reaction rims on amphibole phenocrysts in the same sample.
For clinopyroxene, 74 analyzed points (within 10 samples) have formation pressures > 9 kbar, and 10 points (within 3 samples) have formation pressures < 5 kbar. The majority of clinopyroxene show higher formation pressures than amphibole, with 87% plotting between 4 and 11 kbars. This shows that although formation pressures within clinopyroxene do not provide the restrictive conditions like the pressures for amphibole do (Figure 24), both clinopyroxene and amphibole have only a few samples with formation pressures less than 4 kbar. The relative errors of these pressure and temperatures often overlap samples from different compositions that hinder the interpretation of these results. 26
Compositionally, clinopyroxene in tephriphonolites have the widest range of formation temperatures (959-1050ºC) and the widest range of pressures (2.9-11.1 kbar). Phonolites within these samples have generally higher pressures of mineral formation than tephrite and some basanite compositions. The presence of zoning in clinopyroxene does not generally correlate with temperature or pressure, however there are phenocrysts in samples where the rims formed at lower temperatures than their corresponding cores (e.g., MB07-141 and MB06-827; Figure
28). Unfortunately the estimated error makes the core and rims indistinguishable. 27
CHAPTER IV. DISCUSSION
The results presented in this study expand on previously documented evidence for magma mixing and can be used to explain the complexity of the Minna Bluff magma system.
The amphibole and clinopyroxene phenocrysts provide textural and geochemical evidence of this. Crystallization depths are inferred using geothermobarometry results, which combined with the textural diversity of the amphibole, can then be used to determine whether there was mixing between mafic and more felsic magmas or if fractional crystallization created the diversity of compositions. Combining all of this information makes it possible to further infer the Minna
Hook plumbing system.
Evidence for Magma Mixing
Previous work from Scanlan (2008) has documented physical and mineralogical evidence for magma mixing/comingling for several lavas within a small area on Minna Hook
(Xeno Ridge) and a preliminary evaluation of magma evolution and mixing based on whole rock geochemistry (major and trace elements) for the whole of Minna Bluff by Panter et al.
(2011).
Disequilibrium Textures
Disequilibrium textures displayed by phenocrysts (e.g., reaction rims, zoning) are often used to infer open system processes (e.g., mixing, assimilation) in magmatic systems (Streck,
2008; Scott et al., 2012; Kiss et al., 2014; De Angelis et al., 2015; Marzoli et al., 2015).
Reaction rims on amphibole can provide evidence for disequilibrium caused by changes in pressure and/or temperature (Scott et al., 2012; Rutherford and Devine, 1998; Rutherford and
Devine, 2003; De Angelis et al., 2015). I use amphibole texture and composition, along with 28 clinopyroxene to further evaluate magma mixing in the production of magmas erupted at Minna
Bluff.
Amphibole reaction rims are seen throughout all of the samples, with the majority of the reaction rims falling within the strongly developed category (Table 4). Reaction rims occur on phenocrysts but also on microphenocrysts of amphibole in a few lavas. Microphenocrysts grew in the shallow system just prior to eruption and therefore the weakly developed reaction rims would have had to have formed during eruption as a result of rapid decompression. According to Browne and Gardner (2006) this would have occurred at pressures >.05 kbars (based on a crustal density of 2.8 g/cm3), equivalent to 200 meters or more beneath the surface.
It is difficult differentiating the effects of temperature increase versus decompression on the formation of reaction rims. Most recently, Angelis et al. (2015) conducted heating-induced reaction rim growth experiments in which over half of the results show a reaction rim mean thickness of <40 µm, equivalent to weakly to moderately developed in this study. Angelis et al.
(2015) noted that >70% of the reaction rims formed from the heating experiment have the same rim thickness as those formed from decompression experiments. This indicates that the thickness of the rim cannot be used to determine the cause of the reaction rim as previous studies have suggested (Browne and Gardner, 2003; Rutherford and Hill, 2003; Rutherford and
Hill 1993). Therefore in this study I must consider reaction rim formation in response to both changes in pressure and temperature. The more strongly developed reaction rims occur on amphibole phenocrysts that have average lower pressures of formation (Figure 29) and on amphibole from lavas that yield older eruption ages (Table 10). Furthermore, the older lavas are typically more compositionally evolved, suggesting that they may have stalled or had slower ascent rates to allow for differentiation. 29
In addition to reaction rims, zoning in phenocrysts have been used to explain open system processes in magmas (Streck, 2008; Kiss et al., 2014; Marzoli et al., 2015).
Compositional zoning is documented in nine of the probed amphiboles, and eight of the probed clinopyroxenes (Table 4). Specifically noted is oscillatory and reverse zoning, indicating changes in the melt surrounding the mineral. These changes can occur if a crystal convects within a compositionally stratified magma system or if a new magma of a different composition intrudes and is mixed (Marzoli et al., 2015; Kiss et al., 2014; Rutherford and Devine, 2003;
Devine et al., 1998; Koyaguchi and Blake, 1989). First order evidence for mixing is demonstrated by the occurrence of fluidal-shaped inclusions observed within lavas from Xeno
Ridge (MS-113 and MS-114) as well as by the heterogeneity in the degree of reaction rim development observed by amphibole phenocrysts in these lavas (Scanlan, 2008). A wide range of reaction rim thicknesses have been previously used to support magma mixing (De Angelis et al., 2015).
Mixing may be the reason that mineral zoning does not correlate with reaction rims.
Table 10 shows that strongly zoned amphiboles have weakly developed reaction rims and formed at higher pressures. This may be explained as mixing may have triggered rapid ascent from depth and the reaction rim development was hindered by quick depressurization.
Amphiboles that have undergone zoning through convection in a compositionally stratified magma system may not have obtained reaction rims textures, and if later mixed, may show weakly developed reaction rims if the melt was quickly spurred upward. With the exception of
MS-169, all phenocrysts of clinopyroxene in all samples are zoned. Chemical transects, however, show that the zoning is not as pronounced as the zoning in amphibole (Figure 17).
This could be explained by clinopyroxene crystallizing separately (i.e. before or after 30 amphibole) or that clinopyroxene minerals were physically separated from the magma in which amphibole grew (e.g., not convecting within a stratified system), or that clinopyroxene grew outside the influence of mixing event(s). With clinopyroxene containing less water than amphibole, it has a wider range of temperatures and pressures that it’s stable at, which may also influence textural growth (Bell and Rossman, 1992).
Disequilibrium with Whole Rock
A further test for magma mixing is the consideration of compositional mineral-melt equilibria. The basic premise is that minerals in equilibrium with the melt that they crystallized from will have consistent exchange ratios for certain cations. There is the possibility that during mixing cation were exchanged between the introduced melt and the mineral. This would alter the original chemistry of the mineral and therefore the calculated KD values would not reflect the original exchange conditions. Obtaining the original chemical composition of the melt a mineral first formed in would require analysis of mineral/melt inclusions, which was not part of this study.
There are a significant number of analyses of both amphibole and clinopyroxene phenocrysts that appear out of equilibrium with their lava hosts (Figures 19, 21-23). Amphibole phenocryst cores and rims in samples MB07-025 and MB07-167 plot completely above the
min-liq envelope of equilibrium [KD = (Fe/Mg) = 0.28 ± 0.11] with their host lavas (Figure 22).
The lavas that contain these amphiboles are basanite with Fe/Mg ratios of 0.39 and 0.62, respectively. In order for the amphibole to be in equilibrium with that composition of melt, the
Fe/Mg ratios would need to be 0.25 for sample MB07-025 and 0.30 for sample MB07-167.
Tephriphonolites have Fe/Mg ratios that range from 0.23 to 0.32. Therefore, it is likely that the amphibole in these two samples originally crystallized from a more evolved magma similar to a 31 tephriphonolite. Overall, amphibole cores are more consistently outside of the envelope of equilibrium relative to the rims (Figure 22), especially between amphiboles from lavas with
SiO2 contents that range from 48 to 54 wt. %. This indicates that the core of the mineral crystallized from a slightly different composition than its rim, which may be explained by earlier crystallization in a magma that later mixed with another magma of a different composition. The rims then crystallized from the resulting hybrid composition. The negative correlation of amphibole rims with their whole rock SiO2 contents, which is not as clearly defined as the cores (Figure 22), indicates physical mixing of early formed amphibole crystals within different magma types followed by crystallization of rims from hybrid magmas. Sample
MB07-134 would be just the opposite, with amphibole growing in a more mafic melt and then being mixed with a more evolved melt. There appears to be only a few samples whose cores and rims are in approximate equilibrium with there host lava (i.e. MS-113, MB07-174, MB06-827)
The out-of-equilibrium amphibole cores (± rims) are considered ‘antecrysts’ as they formed from a different magma that they are currently hosted in, but that the precursor magma is related to the same system (Larrea et al., 2013).
The limited number of amphibole cores in equilibrium with the melt while forming
(Figure 22) provides more evidence of the compositionally fluctuating system. Moreover, the compositional variation within the suite of amphiboles (Figure 5) and variations within samples, including differences between cores and rims can be explained if an evolved melt, with amphibole formed at lower temperatures and pressures, was intruded by a more primitive melt with amphibole formed under higher temperatures and pressures. After mixing, amphiboles that originated in the more evolved melt would develop rim compositions that reflect higher temperatures but with the same or lower pressure relative to their cores. The amphibole within 32 the intruding mafic magma would develop lower temperature and pressure rims relative to their cores. Figure 26 depicts a similar situation with amphiboles in which the rims plot at lower formation temperatures and pressure than their core.
Clinopyroxene also exhibit disequilibrium with their host lava (Figure 23).
Clinopyroxene in basanite sample MB07-141 falls out of equilibrium with its host lava with KD values significantly higher than predicted (Figure 23). The whole rock Fe/Mg ratio of the
min-liq basanite is 0.92 but in order to be in equilibrium (KD = (Fe/Mg) = 0.27 ± 0.03) the Fe/Mg ratio for the melt would need to be ~0.30. This value of 0.30 would be the ratio predicted for a tephriphonolite and, once again, indicates that mafic and felsic magmas have been mixed. It is interesting to note that analyzed rims on clinopyroxene in sample MB07-141 have calculated KD values with the host that are closer to equilibrium than their cores (Figure 23), which may be explained by crystallization of the rims occurring before the magmas were fully mixed.
Although amphibole in sample MB07-167 was found to be out of equilibrium with its host, clinopyroxene within the same sample is generally in equilibrium (Figure 23). This suggests that the clinopyroxene crystallized in a basanitic melt prior to being mixed and reinforces the idea that the evolved magma (~tephriphonolite) did not contain clinopyroxene phenocrysts.
In the cases described above for both amphibole and clinopyroxene that exist in basaltic lava at Minna Hook, the mixing between mafic and felsic magmas would have to be in a proportion weighted highly in favor of a more primitive melt in order to produce a hybrid with a basanite composition. Another possibility is that the amphibole represents individual crystals physically incorporated without, or with very little, associated liquid. These antecrysts may be from conduit walls/ floor that were picked up by ascending basanite magma or from melts rising/erupting through mostly crystallized magmas. Antecrysts have been identified through 33 previous studies as minerals that crystallized from a different host magma than that of which they are finally contained (Charlier et al., 2005; Gill et al., 2006; Davidson et al., 2007). Studies have documented antecrysts using mineral ages (Charlier et al., 2005), isotopic variations
(Davidson et al., 2007) and mineral melt equilibria (Gill et al., 2006). In general, the formation of antecrysts occurs as a newer melt intrudes an older magma body, within the same system, that is partly (to wholly) solidified (Charlier et al., 2005; Gill et al., 2006; Davidson et al.,
2007). The newer melt entrains the older mineral(s), slightly changing the composition if partial dissolution occurs (Davidson et al., 2007).
In summary, mixing of magmas within an open system is supported by both textural and compositional evidence. Amphibole reaction rims, visual evidence for zoning along with core to rim compositional transects (Figures 12- 17) all indicate disequilibrium conditions during crystal growth that is likely due to the interaction between different magma batches. Amphibole and clinopyroxene phenocrysts that are out of compositional equilibrium with their host lava indicate mixing of magmas or incorporation of crystal ‘debris’ within a rising magma. A wide range of calculated pressures and temperatures of phenocrysts within individual samples
(Figures 24-29) provide further evidence of disequilibrium in an open system.
Crystallization Depths
Geothermobarometry allows estimations of temperatures and pressures during crystal formation. This is then combined with geophysical evidence to infer where within the general structure of the lithosphere the minerals crystallized. The geothermobarometric calculations indicate that amphibole and clinopyroxene crystallization took place at depths both above and below the lower crust – upper mantle boundary, with some evolved compositions (phonolites) crystallizing at or below this boundary (Figure 24 and 28). 34
The estimated crystallization temperatures for clinopyroxene phenocrysts are higher in more mafic compositions. The estimated crystallization pressures for clinopyroxene phenocrysts however are higher (>10 kbar) in both phonolites and basanites (Figure 28). Few of the clinopyroxene phenocrysts measured in phonolites and basanites plot within melt equilibrium
(Figure 21). The average calculated pressures and temperatures of phonolites plot at lower pressures and temperatures and suggest that the melt in which they formed stagnated at depth or rose very slowly. The basanite compositions formed in similar calculated conditions but did not have the same time to evolve into a more felsic composition (e.g. phonolite, tephriphonolite).
Three samples with coexisting amphibole and clinopyroxene (MB07-167, -827, MS-113) show that clinopyroxene formed at average higher pressures (Table 10), implying that the formation of some clinopyroxene crystals occurs before amphibole crystallization. However, there are several instances where calculated pressures are similar (Table 10).
Evidence for Crystallization near the Crust-Mantle Boundary
Slow ascent or stagnation of magma allows time for magmas to evolve by the process of fractional crystallization and interact with the surrounding rock that they are rising through.
According to the calculated pressures, the majority of amphibole and clinopyroxene crystallization occurs around the depth estimated for the crust-mantle boundary (i.e. the
Mohorovičić discontinuity or Moho) in this region. The transition between ductile and brittle rocks occurs along the Moho, which may affect magma rate of ascent and thus promote crystallization as magmas stall and cool. The transitional effects at this boundary must be taken into consideration when understanding the magmatic system. The uplift of the Transantarctic
Mountains (TAM) and extension of the West Antarctica Rift System thinned the crust beneath the Victoria Land Basin (Behrendt et al., 1991; Fielding et al., 2006). Seismic data were used to 35 examine the structure of the lithosphere across the TAM and into the Ross Sea to deduce crustal thicknesses. Geophysical data around the Victoria Land Basin, including Terror Rift (Figure 1), indicate abnormally high heat flow through seismic studies (Della Vedova et al., 1992;
Bannister et al., 2003; Lawrence et al., 2006; Baranov, 2011), thermobarometry analyses (Della
Vedova et al., 1992; Bannister et al., 2003) and airborne gravity surveys (Lawrence et al., 2006).
These studies are used to estimate the crust-mantle boundary, indicating depths of 16 to 21 km, specifically depths of 19 to 21 km within southern Victoria Land (Della Vedova et al., 1994;
Bannister et al., 2003; Lawrence et al., 2006; Baranov, 2011).
The crustal thickness is important for understanding magma evolution and dynamics during ascent to the surface. The thinner crust and higher heat flow provide a good environment for magma generation in the mantle. This magma generation is then influenced by the surrounding crustal or upper mantle material, affecting ascent rates, cooling and crystallization.
Melts can stall as they rise through material, primarily due to contrasts in densities and/or mechanical aspects throughout the lithosphere (i.e. stress regime and availability of fault systems) (Klügel et al., 2005; Longpré et al., 2008; Thybo and Artemieva, 2013). This stagnation is facilitated by the density contrast that occurs at the mantle-crust boundary (Klügel et al., 2005) and has been previously theorized by numerous studies (Fyfe, 1992; Klügel et al.,
2005; Longpré et al., 2008; Thybo and Artemieva, 2013). These papers have proposed that this stagnation along the Moho is correlated to the magma obtaining neutral buoyancy (magma density becomes equal to that of the host rock) within this region. This buoyancy then allows for magma to ‘pond’ at this level (Klügel et al., 2005; Longpré et al., 2008; Thybo and Artemieva,
2013). The magma stays at this level until there is faulting or the magma differentiates enough, decrease its density, to begin its ascent again (Klügel et al., 2005; Longpré et al., 2008; Thybo 36 and Artemieva, 2013). Other studies support this idea as well, suggesting that the density differences between the crust and mantle causes stagnation, with different magmas rising and stalling at varying depths, allowing magmas to differentiate (Herzberg et al., 1983; Arndt and
Goldstein, 1989). If magmas were to stall and cool at this boundary, fractional crystallization would occur. This stagnation point and the time of residence of magmas can potentially produce a diversity of compositions related to one another through fractional crystallization (Irving and
Green, 2008; O’Reilly and Griffin, 2013). Irving and Green (2008) documented two compositionally distinct alkaline lavas, nepheline basanite and nepheline mugearite, with different mineral assemblages but with the same estimated crystallization depth of ~42 km.
This supports the idea that alkaline magmas can evolve within the lithospheric mantle.
Depth of crystallization is calculated using gravity, pressure and density estimates.
Density is critical when determining depth of fractionation as it differs between mantle and crustal rocks. Depths in this study were estimated based on amphibole and clinopyroxene barometry (Scanlan, 2008) and previous density estimates (Christensen and Mooney, 1995; ten
Brink et al., 1997). An average crustal density of 2.8 g/cm3 was obtained through calculating an average density of 40 km thick continental crust using surface densities (2.66 g/cm3) and densities at the base of the crust (3.1 g/cm3) (Christensen and Mooney, 1995). Since the crust is much thinner in the region of Minna Bluff (19-21 km) mantle density must also be considered to determine equivalent depth based on calculated pressures for clinopyroxene and amphibole.
Using an average upper mantle density under West Antarctica (3.32 g/cm3; ten Brink et al.,
1997) and Christensen and Mooney’s (1995) composite crustal density (2.8 g/cm3) an average density of ~3.1 g/cm3 was obtained. This density is used for pressures that are high enough to be within the upper mantle (>6.3 kbar ≈ >21 km). Using this density to estimate the depth from 37 pressures obtained from amphibole yields 15-23 km for the 29% of the analyses and depths of
22-32 km for the 71% analyses. This suggests that most of the amphiboles formed within the upper mantle. Depths estimated from clinopyroxene barometric calculations using the same average density are 11-23 km for the 14% of the analyses and 22-47 km for the 86% of the analyses. The results also suggest that most of the clinopyroxene formed in the upper mantle but, on average, at greater depth than amphibole. Of the samples, 9% calculated within the pressure range corresponding to the estimated Moho depth (19-21 km) (Della Vedova et al.,
1994; Bannister et al., 2003; Lawrence et al., 2006; Baranov, 2011). This supports that significant crystallization took place around the upper mantle boundary. The stalling of the melt around the Moho (19-21 km ≈5.7-6.3 kbar at 2.8 gm/cm3) would have allowed crystallization to occur. The transition between the upper mantle and crust is a density driven gradational boundary (Klügel et al., 2005; O’Reilly and Griffin, 2013; Thybo and Artemieva, 2013), slowing the melt down, inducing more crystallization. While this aids in understanding crystallization history, ascent paths are complex with the probability of multiple melts and/or replenishments within the system (Scanlan, 2008; Panter et al., 2011; Krans, 2013).
Minna Hook Plumbing System
Combining information of the lithosphere from geophysical data with the textural and geochemical evidence gathered from the samples in this study, an idealized model of the plumbing system underneath Minna Hook was developed. The conceptual model (Figure 30-32) shows magma stagnation, crystallization and mixing levels. This model is a hypothetical generalization of what may have happened in this area, and would have occurred over a wide timespan, with processes occurring multiple times with different batches of magma. A scenario for the progression of magmatic events is as follows: 38
Stage I. Two mafic magmas (Magma #1 and #2) ascend into the upper mantle until they stall at the lower crustal – upper mantle boundary and begin to crystallize clinopyroxene and amphibole. This stagnation may in fact be very slow ascent as the magmas transition through the density-graded Moho boundary. Such a slow ascent allows for the formation of evolved compositions (e.g. phonotephrite, tephriphonolite) producing samples MS-113, MB07-174 and -
184, for example.
Stage II. Another batch of mafic magmas (Magma #3 and Magma #4) begins to slowly rise into the upper mantle and the crystallization of clinopyroxene occurs. Crystallization continues as one part of the mafic magma (Magma #3) stalls while the other magma (Magma #4) rises through the pre-existing conduit system. Magma #3 stagnation allows an evolved composition (e.g. phonolite) to form and explains clinopyroxene within phonolites at high pressures, producing sample MB07-141, for example. Magma #4 beings to crystallize amphibole as it ascends, producing sample MB07-025, -167, and -180A for example. Both magmas are quickly replenished, creating zonation textures within the minerals and weakly developed reaction rims. Magma #4 continues upward, still mafic (e.g. basanite, tephrite) in composition.
Stage III. The mafic magma ascending through the pre-existing conduit system (Magma
#4) encounters the felsic (tephriphonolitic and phonolitic) magmas (Magma #1 and #2). This creates disequilibrium in both clinopyroxene and amphibole minerals. Magma #4 is now considered Hybrid #1, as mixing creates mafic magmas containing evolved amphibole minerals with low temperature and pressure rims and high temperature and pressure cores. As Hybrid #1 does not completely mix with Magma #1 or Magma #2, its whole rock composition stays mafic, producing samples such as MB07-017 and -145. Magma #1 is now considered Hybrid #2 while
Magma #2 is now considered Hybrid #3. Hybrid magmas #2 and #3 contain evolved magmas
39 with mafic amphibole minerals having high temperature, and same or moderate, pressure rims.
Evolved magmas mixing in mafic amphiboles is used to support amphibole cores farther out of equilibrium than their rims, and the range of tephriphonolites and basanites/tephrites. Mixing also explains the zonation and reaction rim textures seen within these compositions. Amphibole crystallization continues. Samples MB07-028, 114 and -134 are good representations for Hybrid
#2, while samples MB06-832 and MB07-174 are used as representations for Hybrid #3.
Stage IV. This mixing event stimulates ascent of Hybrid #1 further through the gradational Moho, with the crystallization of amphibole taking place throughout this transition.
Hybrids #2 and #3 are slower to follow due to their lower temperatures from their stagnation.
Magma #3 continues crystallizing amphibole, becoming more felsic and buoyant, and follows the previous Hybrids #2 and #3 upward.
Stage V. Theoretically, Hybrid #1 (basanites, tephrites) erupts first, with Hybrids #2 and
#3 (phonotephrite, mugearite, tephriphonolite) erupting after, followed lastly by Magma #3
(phonolite).
For those minerals that form at lower temperatures and pressures within Minna Bluff, e.g. phonolites, tephriphonolites, mugearites, this is inferred to be from re-invigorated fractionation due to mixing of magma(s) which then stimulated the crystallization of more mafic minerals.
Implications
This study helps to demonstrate the complexity of the magmatic plumbing system beneath the Minna Bluff area. It reinforces previous studies (Scanlan, 2008; Panter et al., 2011) that suggest magmas within this area underwent mixing and details the specific ways in which magma mixing may have occurred. Understanding the magma reservoir here and its pre- 40 eruptive conditions can shed light on magmatic systems in similar tectonic settings, such as the
East African Rift Zone, and may even help in forecasting eruptions, as the physical and chemical properties of a melt determine a volcano’s eruption style and explosivity (Ridolfi et al., 2010; Angelis et al., 2015). Furthermore this study reinforces the idea that reaction rims and zoning shouldn’t automatically be classified as properties formed during ascent, as mixing could also play a part (Rutherford et al., 1998; Kiss et al., 2014; Angelis et al., 2015; Marzoli et al.,
2015). Additionally, antecryst identification could be used in explaining some of the Minna
Bluff mineral/whole rock variability, which may imply that there wasn’t as much dynamic mixing within this study area as predicted. This study supports the idea of a density driven transition around the Moho, allowing magma ponding at the base of the lower crust/ upper mantle (Griffin and O’Reilly, 1987; O’Reilly and Griffin, 2013; Ghosh et al., 2014) through thermobarometry and whole rock comparisons, indicating the range of fractional crystallization with pressures and evolution. While magma mixing hasn’t been sufficiently evaluated for West
Antarctic volcanism, expect for the few petrogenesis studies done at Mount Sidley (Panter et al.,
1997) and Mount Morning (Martin et al., 2013; 2015), this study has shown that magma mixing and early-stage differentiation is important in alkaline magma genesis within this area. 41
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Table 1: Detailed textural and mineralogical data. This table comprises samples used for analysis and probing, including lava unit descriptions and ages (Fargo, 2009; Wilch et al., 2011; Antibus et al., 2014; Ross, 2014) for this study (Scanlan, 2008; Wilch et al., 2011). 51
Table 2: Empirical thermobarometric formulations for amphibole. Thermobarometer is based on Ridolfi et al. (2010). Temperatures have a standard estimated error of + 22ͼC, the H2O melt has uncertainties up to 15% and the pressure uncertainties range from <11 to 24%, based on the relative stability of the mineral, relative to whole rock composition.
Where P = pressure, R2= statistical measure of how the data aligns to a fitted regression line, Al* = aluminum index, Si* = silicon index, A[ ] = cations within the A site, B[ ] = cations within the B site, C[ ] = cations within the C site, [6]Al = octahedral aluminum, [4]Al = tetrahedral aluminum, AlT = aluminum total. Mineral formulas used by Ridolfi were calculated following the International Mineralogical Association (IMA) recommendation for calcic-amphiboles from Leake et al. (1997). 52
Table 3: Clinopyroxene-liquid thermobarometers. Thermobarometers used are specifically for mafic, evolved, and volatile-bearing lava compositions modified from Putirka et al. (2003). Temperature is in Kelvin and has a standard estimated error (SEE) of 33K. Pressure is in kbar and has an error of + 1.70 kbar.
Jdcpx is the mole fraction of jadeite in clinopyroxene; DiHdcpx is the mole fraction of diopside + hedenbergite in clinopyroxene; Alliq is the liq liq liq liq liq liq liq cation fraction of AlO1.5 in the liquid; Fm is the sum FeO + MgO ; Mg is the cation fraction ratio MgO /(MgO +FeO ). 53
Table 4: Summary of sample compositions and petrological observations. This includes average reaction rim thickness, their corresponding rating based on thickness groupings and information on whether the mineral was zoned. 54
Table 5: Representative amphibole compositions from each sample. Amphiboles are classified based on Esawi (2004), which determines the Fe3+/Fe2+ ratio after adjusting the tetrahedral and octahedral cations to 13 (Leake et al., 1997). 55
(Table 5 continued) 56
Table 6: Representative clinopyroxene compositions from each sample. Samples were classified using the accepted names from Morimoto et al. (1988). 57
Table 7: Compositional variability within whole rock samples. ‘Points’ refer to the number of points probed, ‘Pheno’ refers to the amount of phenocrysts the points were taken from. Samples with > represent those in which the number of phenocrysts wasn’t identified further. Prefixes, modifiers and endmember meanings used in the classification of amphiboles (Leake et al., 1997). 58
Table 8: Transects through zoned amphiboles in sample MB07-174. Transects MB07-174_T (Figure 12 and 13) and MB07-174_B-T (Figure 14 and 15) are split along the core (T9/T10) and (B-T6/B-T7) to depict the variations from core to rim on either side of the minerals. The highlight gray lines show the starting and ending element concentrations in weight %. 59
Table 9: Transect through zoned clinopyroxene in sample MB07-017. The transect (Figure 17) is split along the core (T8/T9) to depict the variations from core to rim on either side of the mineral. The highlight gray lines show the starting and ending element concentrations in weight %. 60
Table 10: Summary and comparison between whole rock compositions, temperatures, pressures, ages, zoning and reaction rims data. Temperature and pressure ranges, and their corresponding errors, are based on thermobarometry studies (Putirka et al., 2003; Ridolfi et al., 2010). Highlighted green boxes focus on amphibole age (Fargo, 2009; Wilch et al., 2011; Antibus et al., 2014; Ross, 2014) and pressure of formation (Ridolfi et al., 2010). Spaces with ‘-’ indicates the data did not fit the requirements of the thermobarometers. Highlighted yellow areas focus on amphibole pressures of formation (Ridolfi et al., 2010) and reaction rims. Zoning and reaction rims are highlighted within the purple dashed boxes. 61
Figure 1: An overview of the McMurdo Volcanic Group (MVG). MVG is highlighted in yellow and is based on Kyle (1990) and Fitzgerald (1992). Image modified from Google Earth. 62
Figure 2: Modified satellite image of the Erebus Volcanic Province (EVP). EVP is outlined with yellow dashed lines and is part of the McMurdo Volcanic Group (MVG) (Fig. 1) located within South Victoria Land. Minna Bluff extends southeast from Mt. Discovery, based on Kyle (1990). The red lines indicate the pattern of volcanism. Image modified from Google Earth. 63
Figure 3: Modified satellite image of Minna Bluff. The image is spilt up into Minna Bluff’s two respective parts – McIntosh Cliffs and Minna Hook. The location of Minna Bluff with respect to Mt. Discovery is shown by the red dashed box within the figure inset (from Fig. 2). The yellow box represents the Xeno Ridge study area from Scanlan (2008). Image modified from Google Earth. 64
Figure 4: Samples used in this study with locations relative to Minna Hook. Image modified from Google Earth. 65
Figure 5: Total alkali silica (TAS) plots. Compositional classification based on LeBas et al. (1986): A. All whole rock data from Minna Bluff samples, B. Whole rock data analyzed from Minna Hook in this study. 66
Figure 6: Pyroxene quadrilaterals. Clinopyroxene and amphibole classifications based on Morimoto et al. (1988): A. Probe analysis from this study, B. Probe analysis also incorporated in this study from Scanlan (2008), C. All core data. D, All rim and unidentified sample data. Unidentified samples were those not labeled as either core or rim. 67
Figure 7: Textural classification representatives. A. Hypohyaline, vitrophyric and pilotaxitic textures seen within MB06-827, B. Aphanitic texture seen within MB07-114, C. Holocrystalline texture seen within MB07-017, D. Hypocrystalline and porphyritic textures seen within MB07-167, E. Trachytic texture seen within MB07-134. 68
Figure 8: Examples of mineral inclusions within amphibole. A. Plagioclase (circled in blue) within sample MB07-174, B. Apatite (circled in red) within sample MB07-028, B. C. Magnetite (circled in green) within sample MB07-017.
69
Figure 9: Amphibole reaction rim classification. The four types of reaction rims: A. Weakly developed reaction rim (0-19μm), sample MB07-181. B. Moderately developed reaction rim (20-40μm), sample MB06-508. C. Strongly developed reaction rim (41-80μm), sample MB07-145. D. Ghost amphibole, sample MB07-017.
70
Figure 10: Examples of zonation within amphibole and clinopyroxene. Amphibole (A, B, C) and clinopyroxene (D, E, F) are pictured underneath plane polarized light, unless otherwise specified: A. MB07-174, B. MB07-114, C. MB07-180A, D. MB07-017 under cross polarized light, E. MB07-167 under cross polarized light, F. MB07-167. 71
Figure 11: TAS diagrams showoing reaction rims and zonation versus composition. Plots are based on LeBas et al. (1986). A. TAS diagram showing the lack of correlation between reaction rim type and whole rock composition, B. TAS diagram showing a slight association between more felsic whole rock sample and amphibole zonation.
72
Figure 12: Transect across amphibole mineral MB07-174_T. The transect was split along the core to depict the variations from core to rim of either side of the mineral. With respect to Mg, yellow arrows indicate reverse zoning, orange arrows indicate normal zoning. Composition is ferropargasite (point 1-2), magnesiohornblende (point 3), ferrokaersutite (point 4-5), kaersutite (point 6-8), ferropargasite (point 9- 10), kaersutite (point 11-12), ferropargasite (point 13-15). 73
Figure 13: Amphibole MB07-174_T transect with Ti, Mg and Fe chemistry. Error is +/- 0.2 wt. %. The transect was split along the core (between T9 and T10) to depict the variations from core to rim of either side of the mineral.
74
Figure 14: Transect across amphibole mineral MB07-174_B-T. The transect was split along the core to depict the variations from core to rim of either side of the mineral. With respect to Mg, yellow arrows indicate reverse zoning, orange arrows indicate normal zoning. Composition is ferropargasite (point 16- 18, ferrokaersutite (point 19), ferropargasite (point 20-21), ferrokaersutite (point 22-25). 75
Figure 15: Amphibole MB07-174_B-T transect with Ti, Mg and Fe chemistry. Error is +/- 0.2 wt. %. The transect was split along the core (between B-T6 and B-T7) to depict the variations from core to rim of either side of the mineral. 76
Figure 16: Amphibole phenocrysts with zoning and weakly developed reaction rims. A, B. MB07-180C, C. MB07-181, D. MB07-114. 77
Figure 17: Ti- and Al- Tschermak substitutions in amphibole. Substitutions are used for temperature and pressure interpretations: A. Increases in formation pressures can be determined through interpreting Al- Tschermak substitutions in amphibole. The samples used in this study do not provide a correlation between components, indicating no systematic change of formation with pressure, B. Temperatures changes can be correlated with Ti-Tschermak substitutions in amphibole. The negative correlation seen in this figure indicates that the formation of amphibole was largely controlled by temperature. Error range: 1.0% uncertainty for > 0.2 wt. %, 10% uncertainty for < 0.2 wt. %. Axes in apfu.
78
Figure 18: Clinopyroxene mineral MB07-017_CC55 transect with Si, Ti, Mg and Fe chemistry. Error is +/- 0.2 wt. %. The transect was split along the core (between T8 and T9) to depict the variations from core to rim of either side of the mineral.
79
Figure 19: Plot of amphibole KD values versus whole rock SiO2. KD is measured as [(Fe/Mg)amp/(Fe/Mg)wr]. Empirically derived KD for amphibole-melt equilibria from Putirka (2016) is shown for comparison.
80
Figure 20: Plot of average amphibole and clinopyroxene KD values versus whole rock SiO2. KD is measured as [(Fe/Mg)amp/(Fe/Mg)wr]. Amphibole and clinopyroxene minerals listed with their corresponding whole rock composition. The sample number is listed above the set of minerals it correlates to. Samples in which the whole composition was inferred are in italics. A linear regression is plotted in the figure through the amphibole minerals showing a good correlation, with r2 plotted on the figure.
81
Figure 21: Plot of clinopyroxene KD values versus whole rock SiO2. KD is measured as [(Fe/Mg)amp/(Fe/Mg)wr]. Empirically derived KD for clinopyroxene-melt equilibria from Putirka et al. (2008) is shown for comparison.
82
Figure 22: Plot of amphibole KD versus whole rock SiO2 with core and rim comparison. KD is measured as [(Fe/Mg)amp/(Fe/Mg)wr]. Empirically derived KD for amphibole-melt equilibria from Putirka (2016) is shown for comparison. The samples are separated into rim and core and the corresponding sample number is shown vertically above.
83
Figure 23: Plot of clinopyroxene KD versus whole rock SiO2 with core and rim comparison. KD is measured as [(Fe/Mg)amp/(Fe/Mg)wr]. Empirically derived KD for clinopyroxene-melt equilibria from Putirka et al. (2008) is shown for comparison. The samples are separated into rim and core and the corresponding sample number is shown vertically above.
84
Figure 24: Amphibole temperature and pressure estimates, separated into core and rim. Values were obtained using thermobarometry techniques with temperature errors of + 22°C and an average pressure uncertainty of +/- 0.68 kbar (Ridolfi et al. 2010).
85
Figure 25: Amphibole temperature and pressure estimates, with core and rim comparisons focusing on whole rock composition. Values were obtained using thermobarometry techniques with temperature errors of + 22°C and average pressure uncertainty of +/- 0.68 kbar (Ridolfi et al. 2010). The area between the orange dashed lines represents the area where most amphibole crystals formed, between 5 and 9 kbar.
86
Figure 26: MB07-145 core and rim comparison. A. Amphibole rims indicating formation at higher temperatures and pressures than their corresponding cores: Arrows show a minerals core to rim trend. Temperature errors are + 22°C and an average pressure uncertainty of +/- 0.68 kbar (Ridolfi et al. 2010), B. Ti-Tschermak substitutions (pressure sensitive), C. Al-Tschermak substitutions (temperature sensitive). B and C have an error range of: 1.0% uncertainty for > 0.2 wt. %, 10% uncertainty for < 0.2 wt. %. Axes in apfu.
87
Figure 27: MB07-181 core and rim comparison. A. Amphibole rims indicating formation at higher temperatures and pressures than their corresponding cores: Arrows show a minerals core to rim trend. Temperature errors are + 22°C and an average pressure uncertainty of +/- 0.68 kbar (Ridolfi et al. 2010), B. Ti-Tschermak substitutions (pressure sensitive), C. Al-Tschermak substitutions (temperature sensitive). B and C have an error range of: 1.0% uncertainty for > 0.2 wt. %, 10% uncertainty for < 0.2 wt. %. Axes in apfu.
88
Figure 28: Clinopyroxene temperature and pressure estimates. Values were obtained using thermobarometry techniques with a temperature error range of + 33°C and the standard estimated error for pressure of 1.7 kbar (Putirka et al. 2003). Top: All samples with clinopyroxene data with corresponding composition. Bottom: Data separated into core and rim. The sample number is listed above the set of minerals it correlates to. The area between the orange dashed lines represents the area where 87% of clinopyroxene crystals formed, between 4 and 11 kbar.
89
Figure 29: Average pressures of formation for amphibole and clinopyroxene versus reaction rim rating. Amphibole values are based on (Ridolfi et al., 2010) and clinopyroxene values are based on (Putirka et al., 2003). Reaction rims ranked "1" extend from 0.5 to 1.5, those ranked “2” extend from 1.6 to 2.5, those ranked “3” extend from 2.6 to 3.8, to give the reader a better view of the distribution.
90
Figure 30: Stage I and II of the magmatic progression. Stage I depicts two mafic magmas ascending into the upper mantle, their slow ascent allowing the formation of evolved compositions. Stage II shows another batch of mafic magmas rising, which are quickly replenished, with Magma #3stalling within the mantle and Magma #4 continuing its ascent upward.
91
Figure 31: Stage III and IV of the magmatic progression. Stage III demonstrates the mixing event occurring between Magma #4 and Magma’s #1 and #2. Magma #4 becomes Hybrid #1 and stays mafic. Magma #3 and #4, now Hybrid #2 and #3, are still evolved in composition. Stage IV depicts the ascent of Hybrid #1, with Hybrid #2 and #3 following. Magma #3 begins its ascent again upward.
92
Figure 32: Stage V of the magmatic progression. This stage shows the theoretical eruption sequence, with Hybrid #1 erupting first, and Hybrid #2 and #3 following, with Magma #3 erupting last.
93 APPENDIX A. ELECTRON ANALYSIS Electron Analysis Host: Amphibole MS169N2-76 MS169N2-75 MS169N2-74 MS169N2-73 MS169N2-72 MS169N2-65 MS169N2-64 Ferri-Potassian Ferri-Titanian Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Magnesiohastingsite Unidentified Unidentified Core Rim Rim Rim Core SiO 39.26 39.67 39.07 39.14 39.12 38.80 39.32 TiO 6.09 5.83 6.15 5.97 6.23 6.00 4.07 AlOΎ 14.31 14.09 14.37 14.27 14.60 14.29 14.24 CrOΏ MgO 11.17 11.76 10.59 10.74 11.52 10.70 9.57 CaO 11.88 11.88 12.02 11.92 12.39 11.89 11.61 MnO 0.20 0.19 0.20 0.19 0.15 0.20 0.27 FeO 12.55 12.45 13.64 13.30 11.68 13.30 15.91 NaO 2.49 2.55 2.48 2.51 2.44 2.43 2.56 KO 1.33 1.20 1.23 1.28 1.21 1.31 1.24 NiO F 0.32 0.31 0.27 0.19 0.13 0.25 0.40 Cl 0.03 0.04 0.02 0.02 0.03 0.02 0.03 Total 99.63 99.96 100.03 99.51 99.49 99.19 99.21
Si 5.778 5.808 5.753 5.778 5.735 5.756 5.894 Ti 0.674 0.642 0.681 0.663 0.687 0.669 0.459 Alƍᵛ 2.202 2.190 2.228 2.200 2.225 2.229 2.121 Al ᵛƍ 0.288 0.242 0.274 0.291 0.313 0.276 0.388 Cr Mg 2.451 2.566 2.324 2.363 2.518 2.367 2.138 Ca 1.872 1.864 1.895 1.885 1.945 1.889 1.865 Mn 0.025 0.024 0.025 0.024 0.019 0.025 0.034 Fe³Ά 1.550 1.524 1.686 1.647 1.441 1.655 1.989 Fe²Ά 0.000 0.000 0.000 0.000 0.000 0.000 0.000 Na 0.709 0.724 0.707 0.719 0.693 0.697 0.744 K 0.250 0.224 0.231 0.240 0.227 0.248 0.237 Ni
Mg# 100.00 100.00 100.00 100.00 100.00 100.00 100.00 Structural formulae on the basis of 24 O. Spaces left blank denote no data was collected for that oxide/element 94 Electron Analysis Host: Amphibole MS169N2-63 MS169N2-62 MS169N2-61 MS169N2-56 MS169N2-55 MS169N2-49 MS169N2-48 MS169N2-47
Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Rim Mantle Core Rim Core Rim Mantle Core SiO 38.72 38.91 38.14 39.49 38.74 39.21 39.00 39.02 TiO 6.28 6.24 6.34 5.88 6.25 6.01 6.04 6.19 AlOΎ 14.59 14.49 14.47 14.16 14.74 14.19 14.27 14.65 CrOΏ MgO 10.92 10.90 9.80 11.33 11.12 10.99 10.71 10.68 CaO 11.88 11.95 11.58 11.93 12.16 11.99 11.95 12.06 MnO 0.18 0.17 0.25 0.16 0.18 0.20 0.20 0.14 FeO 13.11 12.85 14.37 12.52 12.07 12.63 13.17 13.06 NaO 2.42 2.43 2.52 2.41 2.40 2.45 2.43 2.39 KO 1.25 1.24 1.21 1.30 1.28 1.26 1.20 1.23 NiO F 0.23 0.25 0.10 0.28 0.31 0.17 0.21 0.14 Cl 0.01 0.03 0.03 0.01 0.02 0.02 0.02 0.02 Total 99.57 99.43 98.80 99.47 99.27 99.12 99.20 99.57
Si 5.712 5.741 5.702 5.812 5.714 5.793 5.773 5.744 Ti 0.697 0.693 0.713 0.651 0.693 0.668 0.672 0.685 Alƍᵛ 2.281 2.239 2.287 2.172 2.253 2.178 2.206 2.229 Al ᵛƍ 0.258 0.289 0.266 0.290 0.323 0.304 0.292 0.325 Cr Mg 2.401 2.397 2.184 2.486 2.446 2.419 2.364 2.343 Ca 1.877 1.889 1.855 1.881 1.921 1.898 1.895 1.902 Mn 0.022 0.021 0.031 0.020 0.022 0.025 0.025 0.017 Fe³Ά 1.619 1.590 1.800 1.545 1.498 1.568 1.636 1.616 Fe²Ά 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 Na 0.691 0.694 0.729 0.689 0.687 0.701 0.696 0.683 K 0.235 0.232 0.231 0.244 0.240 0.237 0.227 0.230 Ni
Mg# 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 Structural formulae on the basis of 24 O. Spaces left blank denote no data was collected for that oxide/element 95 Electron Analysis Host: Amphibole MS169N2-46 MS169N2-44 MS169N2-43 MS169N2-42 MS169N2-26 MS169N2-18 MS169N2-11 MS169N2-10
Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Core Unidentified Core Rim Unidentified Unidentified Unidentified Unidentified SiO 38.34 39.21 39.57 39.17 39.70 39.14 40.12 39.69 TiO 6.49 5.87 5.86 5.76 5.55 6.29 5.80 5.51 AlOΎ 15.40 14.35 13.80 13.73 13.85 14.97 13.73 13.57 CrOΏ MgO 12.47 11.09 11.29 8.71 11.54 12.45 11.56 11.32 CaO 12.33 12.00 12.02 11.59 11.84 12.24 11.95 11.86 MnO 0.13 0.17 0.15 0.26 0.20 0.12 0.18 0.21 FeO 10.27 12.56 12.46 16.40 12.27 10.24 12.38 12.72 NaO 2.27 2.65 2.52 2.53 2.47 2.26 2.63 2.57 KO 1.14 1.28 1.30 1.27 1.21 1.27 1.31 1.28 NiO F 0.20 0.14 0.21 0.12 0.21 0.29 0.19 0.19 Cl 0.01 0.02 0.02 0.02 0.01 0.01 0.04 0.02 Total 99.06 99.33 99.21 99.55 98.84 99.27 99.89 98.92
Si 5.613 5.780 5.838 5.855 5.865 5.714 5.872 5.877 Ti 0.715 0.650 0.651 0.648 0.617 0.690 0.638 0.614 Alƍᵛ 2.378 2.188 2.129 2.120 2.123 2.266 2.100 2.103 Al ᵛƍ 0.284 0.318 0.284 0.309 0.292 0.319 0.280 0.272 Cr 0.000 Mg 2.721 2.437 2.484 1.940 2.541 2.711 2.522 2.498 Ca 1.935 1.894 1.900 1.857 1.873 1.915 1.873 1.881 Mn 0.016 0.021 0.019 0.033 0.024 0.014 0.022 0.026 Fe³Ά 1.259 1.557 1.545 1.735 1.519 1.254 1.523 1.580 Fe²Ά 0.000 0.000 0.000 0.324 0.000 0.000 0.000 0.000 Na 0.645 0.757 0.722 0.732 0.707 0.639 0.747 0.736 K 0.213 0.241 0.244 0.242 0.228 0.237 0.244 0.242 Ni
Mg# 100.00 100.00 100.00 85.68 100.00 100.00 100.00 100.00 Structural formulae on the basis of 24 O. Spaces left blank denote no data was collected for that oxide/elemen 96 Electron Analysis Host: Amphibole MS169N2-09 MS169N2-07 MS169D-76 MS169D-72 MS169D-58 MS169D-53 MS169D-44 MS169D-40 Ferri-Potassian Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Kaersutite Unidentified Unidentified Unidentified Unidentified Unidentified Unidentified Unidentified Unidentified SiO 39.66 37.50 37.49 37.89 38.29 37.43 37.85 37.93 TiO 5.83 6.66 6.29 6.44 5.19 6.17 5.76 6.00 AlOΎ 13.83 14.77 14.60 14.62 14.01 14.71 14.30 13.86 CrOΏ MgO 11.28 10.94 10.85 10.96 11.74 9.68 10.11 11.01 CaO 11.90 11.81 12.12 12.31 11.79 12.22 11.97 12.27 MnO 0.18 0.18 0.23 0.19 0.19 0.26 0.22 0.20 FeO 12.65 12.66 12.79 12.28 11.95 14.51 14.39 12.89 NaO 2.50 2.63 2.62 2.42 2.53 2.45 2.54 2.52 KO 1.31 1.31 1.24 1.18 1.29 1.24 1.26 1.34 NiO F 0.24 0.18 0.11 0.21 0.32 0.16 0.17 0.29 Cl 0.02 0.02 0.02 0.02 0.03 0.02 0.03 0.03 Total 99.41 98.65 98.35 98.52 97.32 98.84 98.59 98.36
Si 5.843 5.593 5.613 5.645 5.767 5.620 5.690 5.695 Ti 0.646 0.747 0.708 0.722 0.588 0.697 0.651 0.678 Alƍᵛ 2.134 2.393 2.365 2.321 2.235 2.354 2.299 2.276 Al ᵛƍ 0.276 0.208 0.222 0.261 0.251 0.261 0.238 0.189 Cr 0.000 Mg 2.478 2.432 2.421 2.435 2.635 2.166 2.265 2.465 Ca 1.879 1.887 1.944 1.964 1.902 1.965 1.927 1.973 Mn 0.023 0.023 0.029 0.023 0.024 0.033 0.028 0.025 Fe³Ά 1.565 1.582 1.608 1.539 1.504 1.725 1.812 1.627 Fe²Ά 0.000 0.000 0.000 0.000 0.000 0.105 0.000 0.000 Na 0.714 0.761 0.761 0.698 0.739 0.713 0.740 0.733 K 0.247 0.249 0.236 0.225 0.248 0.237 0.241 0.257 Ni
Mg# 100.00 100.00 100.00 100.00 100.00 95.36 100.00 100.00 Structural formulae on the basis of 24 O. Spaces left blank denote no data was collected for that oxide/element 97 Electron Analysis Host: Amphibole MS169D-39 MS169D-06 MS169D-05 MS169D-04 MS169C-36 MS169C-09 MS169C-08 MS169C-04 Ferri-Potassian Ferri-Potassian Kaersutite Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Unidentified Unidentified Rim Core Unidentified Rim Core Rim SiO 38.44 38.28 38.89 38.10 38.51 37.91 37.56 39.04 TiO 5.08 6.09 6.52 6.40 6.12 6.07 6.30 5.61 AlOΎ 13.81 14.33 14.28 15.04 14.29 14.63 15.28 13.82 CrOΏ 0.05 0.01 0.01 0.00 MgO 10.90 11.24 12.51 11.10 11.32 9.70 10.67 11.31 CaO 11.76 12.21 12.35 12.30 12.09 11.66 12.13 11.94 MnO 0.20 0.19 0.13 0.16 0.19 0.22 0.17 0.22 FeO 13.36 12.22 10.33 12.16 12.56 14.44 13.04 13.00 NaO 2.62 2.60 2.60 2.62 2.45 2.41 2.43 2.70 KO 1.45 1.34 1.03 1.24 1.26 1.12 1.20 1.31 NiO 0.00 0.00 0.00 0.00 F 2.70 0.91 0.98 1.15 0.31 0.46 0.37 0.18 Cl 0.04 0.02 0.02 0.01 0.02 0.04 0.02 0.03 Total 100.35 99.41 99.64 100.27 99.17 98.66 99.19 99.14
Si 5.795 5.693 5.711 5.625 5.706 5.696 5.584 5.790 Ti 0.576 0.681 0.720 0.711 0.682 0.686 0.705 0.625 Alƍᵛ 2.197 2.272 2.256 2.339 2.281 2.299 2.405 2.197 Al ᵛƍ 0.260 0.254 0.230 0.295 0.221 0.294 0.277 0.223 Cr 0.000 0.000 0.006 0.001 0.002 0.000 Mg 2.448 2.492 2.739 2.443 2.500 2.172 2.364 2.500 Ca 1.900 1.945 1.943 1.946 1.918 1.877 1.932 1.897 Mn 0.026 0.023 0.016 0.020 0.024 0.029 0.021 0.028 Fe³Ά 1.686 1.530 1.275 1.510 1.559 1.816 1.624 1.616 Fe²Ά 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 Na 0.765 0.749 0.741 0.751 0.703 0.701 0.700 0.775 K 0.279 0.255 0.192 0.233 0.238 0.215 0.228 0.247 Ni 0.000 0.000 0.000 0.000
Mg# 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 Structural formulae on the basis of 24 O. Spaces left blank denote no data was collected for that oxide/element 98 Electron Analysis Host: Amphibole MS169C-03 MS169C-02 MS169B1-67 MS169B1-66 MS169B1-52 MS169B1-51 MS169B1-50 MS169B1-49 Ferri-Potassian Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Kaersutite Mantle Core Rim Core Mantle Mantle Core Rim SiO 38.43 38.35 39.41 38.79 38.95 37.36 38.92 39.55 TiO 5.77 5.84 5.52 6.22 5.93 6.90 5.88 5.40 AlOΎ 14.11 14.16 13.89 14.33 14.07 15.51 14.18 14.28 CrOΏ 0.03 0.02 0.00 0.01 0.03 0.02 0.00 0.00 MgO 9.38 9.51 10.85 9.79 10.70 11.56 10.55 10.32 CaO 11.79 11.83 11.79 11.95 11.88 12.26 12.08 11.75 MnO 0.23 0.21 0.22 0.24 0.20 0.10 0.23 0.26 FeO 15.19 15.10 13.27 14.14 13.44 11.56 13.65 14.15 NaO 2.53 2.51 2.55 2.59 2.56 2.33 2.43 2.61 KO 1.13 1.17 1.27 1.18 1.26 1.13 1.25 1.39 NiO 0.00 0.01 0.02 0.00 0.00 0.03 0.00 0.00 F 0.33 0.26 0.50 0.45 0.36 0.35 0.42 0.33 Cl 0.02 0.02 0.04 0.03 0.03 0.01 0.03 0.03 Total 98.93 98.99 99.31 99.72 99.42 99.11 99.62 100.06
Si 5.769 5.750 5.846 5.757 5.775 5.519 5.769 5.835 Ti 0.652 0.658 0.616 0.695 0.662 0.767 0.655 0.599 Alƍᵛ 2.211 2.233 2.138 2.204 2.206 2.472 2.210 2.149 Al ᵛƍ 0.293 0.277 0.296 0.320 0.261 0.233 0.276 0.341 Cr 0.003 0.003 0.000 0.001 0.003 0.002 0.000 0.000 Mg 2.100 2.127 2.399 2.167 2.366 2.547 2.331 2.269 Ca 1.895 1.900 1.874 1.900 1.887 1.941 1.918 1.857 Mn 0.030 0.027 0.028 0.030 0.025 0.013 0.029 0.032 Fe³Ά 1.778 1.793 1.650 1.624 1.672 1.430 1.698 1.751 Fe²Ά 0.136 0.106 0.000 0.143 0.000 0.000 0.000 0.000 Na 0.738 0.729 0.732 0.744 0.737 0.668 0.698 0.747 K 0.215 0.224 0.241 0.223 0.239 0.212 0.237 0.261 Ni 0.000 0.002 0.002 0.000 0.000 0.003 0.000 0.000
Mg# 93.92 95.24 100.00 93.82 100.00 100.00 100.00 100.00 Structural formulae on the basis of 24 O. Spaces left blank denote no data was collected for that oxide/element 99 Electron Analysis Host: Amphibole MS169B1-42 MS169B1-41 MS169B1-40 MS169B1-36 MS169B1-20 MS169B1-19 MS169B1-09 MS169A-68 Ferri-Potassian Ferri-Potassian Ferri-Potassian Ferri-Potassian Kaersutite Kaersutite Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Kaersutite Ferri-Kaersutite Mantle Core Rim Unidentified Core Rim Unidentified Rim SiO 39.07 38.95 38.57 38.88 38.25 38.70 37.62 38.47 TiO 4.92 5.02 4.93 5.77 6.11 6.18 6.21 6.12 AlOΎ 12.98 12.92 12.79 14.06 14.72 14.31 14.34 14.28 CrOΏ 0.01 0.02 0.00 0.00 0.00 0.02 0.03 MgO 6.53 6.52 6.19 11.13 11.01 12.22 10.80 11.08 CaO 11.47 11.47 11.11 11.89 11.85 12.11 11.85 11.58 MnO 0.39 0.44 0.45 0.21 0.18 0.18 0.17 0.17 FeO 20.21 20.46 20.99 13.16 12.06 12.98 13.46 12.36 NaO 2.75 2.78 2.76 2.76 2.45 2.72 2.50 2.64 KO 1.34 1.33 1.29 1.29 1.06 1.22 1.34 1.23 NiO 0.02 0.00 0.00 0.00 0.01 0.01 0.00 F 0.49 0.25 0.44 0.55 0.35 0.42 0.15 0.34 Cl 0.05 0.05 0.05 0.02 0.03 0.03 0.02 0.03 Total 100.22 100.22 99.56 99.72 98.08 101.09 98.48 98.29
Si 5.940 5.918 5.925 5.758 5.708 5.647 5.640 5.741 Ti 0.562 0.574 0.570 0.642 0.686 0.678 0.700 0.687 Alƍᵛ 2.028 2.055 2.067 2.228 2.275 2.376 2.359 2.244 Al ᵛƍ 0.311 0.269 0.252 0.232 0.322 0.074 0.174 0.274 Cr 0.001 0.002 0.000 0.000 0.000 0.002 0.003 Mg 1.479 1.477 1.417 2.458 2.450 2.657 2.414 2.464 Ca 1.869 1.868 1.828 1.887 1.895 1.892 1.902 1.851 Mn 0.050 0.056 0.058 0.027 0.022 0.023 0.022 0.021 Fe³Ά 1.687 1.728 1.859 1.633 1.510 1.577 1.687 1.546 Fe²Ά 0.896 0.883 0.841 0.000 0.000 0.000 0.000 0.000 Na 0.811 0.820 0.821 0.791 0.709 0.769 0.728 0.764 K 0.259 0.258 0.253 0.244 0.201 0.227 0.256 0.234 Ni 0.002 0.000 0.000 0.000 0.001 0.001 0.000
Mg# 62.27 62.60 62.76 100.00 100.00 100.00 100.00 100.00 Structural formulae on the basis of 24 O. Spaces left blank denote no data was collected for that oxide/element 100 Electron Analysis Host: Amphibole MS169A-67 MS169A-66 MS169A-46 MS169A-45 MS169A-44 MS169A-41 MS169A-40 MS169A-39 Ferri-Potassian- Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Mantle Core Core Rim Rim Rim Mantle Core SiO 38.45 38.66 38.80 38.44 38.78 38.34 37.89 38.82 TiO 6.16 6.04 5.88 6.13 5.88 5.89 6.22 5.80 AlOΎ 14.45 14.57 13.78 14.06 13.98 14.12 14.75 13.51 CrOΏ MgO 10.84 10.93 10.51 10.52 10.32 9.62 11.16 9.07 CaO 11.92 11.88 11.62 11.71 11.67 11.66 12.02 11.67 MnO 0.17 0.15 0.20 0.18 0.22 0.27 0.17 0.23 FeO 12.32 12.19 13.32 13.09 13.65 14.41 11.62 15.08 NaO 2.43 2.38 2.55 2.57 2.41 2.65 2.45 2.48 KO 1.13 1.16 1.23 1.19 1.34 1.14 1.15 1.21 NiO F 0.28 0.28 0.19 0.22 0.37 0.18 0.20 0.26 Cl 0.02 0.02 0.03 0.02 0.01 0.02 0.02 0.02 Total 98.18 98.26 98.09 98.11 98.62 98.28 97.64 98.13
Si 5.736 5.754 5.815 5.759 5.800 5.767 5.670 5.865 Ti 0.692 0.676 0.662 0.691 0.661 0.667 0.701 0.659 Alƍᵛ 2.236 2.222 2.164 2.216 2.183 2.207 2.302 2.092 Al ᵛƍ 0.317 0.344 0.278 0.278 0.289 0.307 0.312 0.330 Cr Mg 2.411 2.424 2.349 2.349 2.302 2.158 2.489 2.043 Ca 1.906 1.893 1.865 1.880 1.869 1.878 1.927 1.888 Mn 0.021 0.019 0.025 0.022 0.028 0.034 0.021 0.029 Fe³Ά 1.544 1.524 1.675 1.646 1.712 1.725 1.461 1.607 Fe²Ά 0.000 0.000 0.000 0.000 0.000 0.096 0.000 0.312 Na 0.703 0.687 0.739 0.745 0.697 0.772 0.710 0.727 K 0.215 0.220 0.234 0.227 0.256 0.218 0.220 0.233 Ni
Mg# 100.00 100.00 100.00 100.00 100.00 95.76 100.00 86.75 Structural formulae on the basis of 24 O. Spaces left blank denote no data was collected for that oxide/element 101 Electron Analysis Host: Amphibole MS169A-38 MS169A-37 MS169A-36 MS169A-24 MS169A-23 MS169A-22 MS169A-17 MS169A-07
Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Rim Mantle Core Rim Mantle Core Unidentified Core SiO 37.99 37.46 38.92 38.32 38.07 38.25 38.42 38.21 TiO 6.21 5.92 5.66 5.92 6.51 6.05 5.79 5.40 AlOΎ 14.74 13.50 13.38 14.25 15.33 14.47 14.19 13.94 CrOΏ MgO 11.05 9.01 8.14 10.08 12.06 9.72 10.77 7.43 CaO 12.06 11.94 11.39 11.46 12.05 11.71 11.67 11.42 MnO 0.14 0.25 0.30 0.22 0.12 0.21 0.18 0.37 FeO 11.66 15.12 16.60 13.61 10.12 13.57 12.81 18.20 NaO 2.31 2.43 2.46 2.41 2.21 2.39 2.50 2.60 KO 1.09 1.24 1.22 1.19 1.10 1.18 1.24 1.16 NiO F 0.18 0.13 0.22 0.26 0.22 0.19 0.26 0.20 Cl 0.02 0.01 0.04 0.04 0.00 0.01 0.03 0.03 Total 97.45 97.01 98.31 97.78 97.80 97.74 97.86 98.97
Si 5.690 5.748 5.904 5.772 5.636 5.757 5.765 5.809 Ti 0.699 0.683 0.645 0.670 0.725 0.685 0.653 0.618 Alƍᵛ 2.282 2.209 2.061 2.218 2.350 2.209 2.220 2.177 Al ᵛƍ 0.333 0.250 0.344 0.315 0.332 0.373 0.296 0.327 Cr 0.000 0.000 Mg 2.467 2.060 1.840 2.263 2.663 2.180 2.408 1.683 Ca 1.935 1.963 1.851 1.850 1.912 1.888 1.876 1.860 Mn 0.018 0.032 0.038 0.028 0.015 0.027 0.023 0.048 Fe³Ά 1.467 1.598 1.666 1.717 1.257 1.670 1.612 1.815 Fe²Ά 0.000 0.357 0.452 0.000 0.000 0.048 0.000 0.504 Na 0.671 0.723 0.725 0.705 0.635 0.699 0.728 0.767 K 0.209 0.242 0.236 0.229 0.208 0.226 0.237 0.225 Ni
Mg# 100.00 85.23 80.28 100.00 100.00 97.84 100.00 76.97 Structural formulae on the basis of 24 O. Spaces left blank denote no data was collected for that oxide/element 102 Electron Analysis Host: Amphibole MS169A-06 MS169A-05 MS169A-04 MS114A-68 MS114A-67 MS114A-66 MS114A-65 MS114A-64 Ferri-Potassian Ferri-Potassian Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Kaersutite Rim Rim Core Core Rim Rim Core Core SiO 38.55 38.96 38.32 39.07 39.08 38.69 38.21 39.20 TiO 5.61 5.64 5.97 4.54 5.15 5.54 4.85 4.72 AlOΎ 14.32 14.21 14.32 13.13 13.27 13.85 13.65 12.58 CrOΏ MgO 11.10 8.39 9.07 7.32 9.15 9.91 6.59 8.35 CaO 11.91 11.54 11.79 11.09 11.52 11.60 11.23 11.33 MnO 0.14 0.28 0.24 0.42 0.32 0.25 0.45 0.39 FeO 12.73 16.97 15.05 19.07 15.96 14.19 19.40 17.27 NaO 2.67 2.79 2.63 2.61 2.65 2.63 2.59 2.61 KO 0.95 1.19 1.16 1.29 1.29 1.17 1.16 1.30 NiO F 0.25 0.17 0.17 0.07 0.17 0.19 0.15 0.09 Cl 0.03 0.02 0.02 0.06 0.04 0.03 0.04 0.04 Total 98.25 100.17 98.74 98.66 98.60 98.04 98.31 97.87
Si 5.753 5.808 5.754 5.967 5.899 5.825 5.876 5.992 Ti 0.630 0.633 0.674 0.521 0.585 0.628 0.561 0.543 Alƍᵛ 2.237 2.171 2.207 2.036 2.082 2.153 2.113 1.991 Al ᵛƍ 0.287 0.335 0.344 0.325 0.286 0.313 0.365 0.282 Cr 0.000 0.000 0.000 0.000 0.000 Mg 2.469 1.864 2.031 1.667 2.060 2.223 1.511 1.904 Ca 1.905 1.844 1.896 1.814 1.863 1.871 1.851 1.856 Mn 0.018 0.036 0.030 0.054 0.041 0.032 0.059 0.051 Fe³Ά 1.591 1.760 1.634 1.936 1.786 1.760 1.838 1.796 Fe²Ά 0.000 0.364 0.268 0.497 0.235 0.033 0.662 0.418 Na 0.771 0.806 0.765 0.772 0.776 0.767 0.771 0.772 K 0.180 0.226 0.223 0.251 0.247 0.224 0.228 0.254 Ni
Mg# 100.00 83.68 88.32 77.02 89.76 98.52 69.54 82.01 Structural formulae on the basis of 24 O. Spaces left blank denote no data was collected for that oxide/element 103 Electron Analysis Host: Amphibole MS114A-63 MS114A-62 MS114A-61 MS114A-51 MS114A-50 MS114A-49 MS114A-44 Ferri-Potassian Ferri-Potassian Ferri-Potassian Titanian Ferri-Kaersutite Kaersutite Kaersutite Ferri-Kaersutite Ferri-Kaersutite Mangesiohastingsite Ferri-Kaersutite Rim Rim Core Unidentified Rim Core Unidentified SiO 39.20 38.87 38.49 38.73 39.04 38.77 37.41 TiO 5.01 5.14 4.77 5.03 5.18 4.20 6.13 AlOΎ 13.18 13.40 13.19 13.96 13.56 12.85 14.33 CrOΏ MgO 9.01 9.09 6.85 10.05 9.69 5.68 9.95 CaO 11.39 11.39 11.09 11.60 11.38 10.79 11.23 MnO 0.30 0.29 0.42 0.20 0.22 0.57 0.21 FeO 16.00 15.73 19.23 13.96 14.67 21.39 13.50 NaO 2.55 2.76 2.62 2.49 2.72 2.71 2.63 KO 1.23 1.30 1.30 1.20 1.13 1.33 1.26 NiO F 0.21 0.17 0.19 0.24 0.16 0.07 0.32 Cl 0.04 0.04 0.05 0.05 0.03 0.09 0.03 Total 98.11 98.17 98.19 97.52 97.77 98.45 97.00
Si 5.942 5.889 5.927 5.855 5.896 6.007 5.696 Ti 0.571 0.585 0.552 0.572 0.588 0.489 0.702 Alƍᵛ 2.044 2.088 2.062 2.132 2.086 1.994 2.293 Al ᵛƍ 0.316 0.314 0.336 0.361 0.335 0.352 0.283 Cr 0.000 0.000 0.000 Mg 2.036 2.052 1.572 2.266 2.182 1.313 2.259 Ca 1.849 1.849 1.829 1.879 1.841 1.791 1.831 Mn 0.039 0.037 0.055 0.026 0.028 0.074 0.027 Fe³Ά 1.816 1.751 1.839 1.769 1.788 1.921 1.723 Fe²Ά 0.217 0.250 0.641 0.000 0.070 0.850 0.000 Na 0.748 0.811 0.783 0.731 0.798 0.813 0.776 K 0.237 0.252 0.255 0.231 0.217 0.264 0.244 Ni
Mg# 90.38 89.15 71.04 100.00 96.90 60.70 100.00 Structural formulae on the basis of 24 O. Spaces left blank denote no data was collected for that oxide/element 104 Electron Analysis Host: Amphibole MS114A-43 MS114A-42 MS114A-41 MS114A-40 MS114A-28 MS114A-27 MS114A-25 Ferri-PotassianTitanian Ferri-Kaersutite Magnesiohastingsite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Rim Core Rim Core Rim Core Unidentified SiO 37.90 38.42 37.94 38.20 39.02 39.07 38.84 TiO 6.22 4.02 6.25 6.22 4.96 5.49 5.17 AlOΎ 14.92 12.86 14.37 14.63 13.09 13.63 13.70 CrOΏ MgO 11.74 6.46 10.42 11.08 8.91 11.13 10.03 CaO 11.64 10.66 11.67 11.59 11.40 11.67 11.56 MnO 0.15 0.55 0.23 0.16 0.30 0.15 0.24 FeO 11.10 20.33 12.78 11.65 15.84 12.20 13.99 NaO 2.60 2.49 2.73 2.79 2.75 2.76 2.68 KO 1.15 1.30 1.14 1.13 1.24 1.14 1.14 NiO F 0.20 0.17 0.22 0.22 0.15 0.17 0.15 Cl 0.01 0.04 0.02 0.03 0.04 0.02 0.05 Total 97.63 97.28 97.76 97.69 97.70 97.43 97.55
Si 5.655 5.996 5.705 5.710 5.939 5.861 5.868 Ti 0.698 0.471 0.707 0.700 0.568 0.619 0.587 Alƍᵛ 2.341 2.032 2.264 2.260 2.030 2.106 2.110 Al ᵛƍ 0.283 0.323 0.295 0.330 0.331 0.316 0.339 Cr 0.000 0.000 0.000 Mg 2.610 1.503 2.336 2.470 2.022 2.489 2.259 Ca 1.860 1.782 1.879 1.856 1.859 1.876 1.871 Mn 0.019 0.072 0.030 0.021 0.039 0.019 0.031 Fe³Ά 1.386 2.114 1.616 1.464 1.697 1.539 1.758 Fe²Ά 0.000 0.527 0.000 0.000 0.330 0.000 0.016 Na 0.752 0.755 0.795 0.809 0.812 0.804 0.783 K 0.219 0.259 0.219 0.215 0.240 0.218 0.220 Ni
Mg# 100.00 74.04 100.00 100.00 85.97 100.00 99.31 Structural formulae on the basis of 24 O. Spaces left blank denote no data was collected for that oxide/element 105 Electron Analysis Host: Amphibole MS114A-24 MS114A-23 MS114A-18 MS114A-17 MS114A-16 MS114A-15 MS114A-08 MS114A-07 Ferri-Potassian Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Rim Core Unidentified Rim Core Unidentified Unidentified Unidentified SiO 38.72 38.03 37.03 38.81 38.17 38.88 38.24 39.10 TiO 5.07 6.09 6.27 5.16 5.69 5.16 5.52 5.48 AlOΎ 13.25 13.95 14.88 13.25 14.22 13.53 13.74 12.95 CrOΏ MgO 8.90 10.18 10.70 8.93 10.25 9.76 10.06 9.95 CaO 11.42 11.51 11.28 11.49 11.61 11.55 11.37 11.44 MnO 0.35 0.20 0.19 0.33 0.21 0.26 0.27 0.28 FeO 15.92 13.14 12.42 15.59 13.50 14.20 14.05 14.09 NaO 2.54 2.64 2.69 2.65 2.57 2.59 2.83 2.95 KO 1.27 1.20 1.23 1.30 1.25 1.15 1.11 1.03 NiO F 0.09 0.15 0.23 0.24 0.23 0.21 0.19 0.19 Cl 0.02 0.02 0.01 0.04 0.02 0.04 0.04 0.03 Total 97.55 97.09 96.94 97.78 97.70 97.32 97.42 97.48
Si 5.903 5.760 5.612 5.906 5.757 5.895 5.799 5.918 Ti 0.581 0.694 0.715 0.590 0.645 0.589 0.630 0.623 Alƍᵛ 2.079 2.210 2.388 2.060 2.227 2.078 2.190 2.044 Al ᵛƍ 0.308 0.293 0.270 0.331 0.307 0.350 0.270 0.281 Cr 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 Mg 2.022 2.299 2.417 2.025 2.305 2.206 2.275 2.246 Ca 1.866 1.868 1.832 1.874 1.875 1.876 1.846 1.854 Mn 0.045 0.026 0.024 0.043 0.027 0.033 0.034 0.036 Fe³Ά 1.788 1.673 1.574 1.670 1.707 1.722 1.785 1.645 Fe²Ά 0.247 0.000 0.000 0.326 0.000 0.087 0.000 0.150 Na 0.752 0.774 0.790 0.781 0.752 0.760 0.832 0.865 K 0.247 0.232 0.237 0.253 0.240 0.222 0.215 0.199 Ni
Mg# 89.12 100.00 100.00 86.13 100.00 96.19 100.00 93.72 Structural formulae on the basis of 24 O. Spaces left blank denote no data was collected for that oxide/element 106
Electron Analysis Host: Amphibole MS114A-06 MS114A-02 MS113A-69 MS113A-68 MS113A-67 MS113A-66 MS113A-65 MS113A-64 Ferri-Potassian Ferri-Potassian- Ferri-Potassian Kaersutite Ferri-Kaersutite Ferri-Kaersutite Kaersutite Ferri-Kaersutite Ferri-Kaersutite Kaersutite Ferri-Kaersutite Unidentified Unidentified Rim Rim Core Core Rim Rim SiO 38.96 38.83 37.97 38.23 37.37 38.56 38.68 38.07 TiO 4.91 4.94 5.99 5.79 6.60 5.61 5.87 6.09 AlOΎ 13.00 13.26 14.11 14.15 15.23 13.63 13.80 14.09 CrOΏ MgO 8.72 8.62 10.67 9.91 11.67 9.29 10.66 10.64 CaO 11.49 11.30 11.55 11.66 11.99 11.67 11.74 11.85 MnO 0.41 0.34 0.23 0.21 0.10 0.26 0.19 0.19 FeO 16.53 16.19 12.67 13.67 10.86 14.79 12.99 12.51 NaO 2.62 2.55 2.43 2.35 2.27 2.43 2.34 2.37 KO 1.32 1.23 1.26 1.36 1.13 1.17 1.32 1.25 NiO F 0.19 0.18 0.25 0.23 0.19 0.13 0.29 0.18 Cl 0.02 0.05 0.02 0.03 0.04 0.03 0.02 0.02 Total 98.17 97.49 97.15 97.59 97.44 97.55 97.89 97.27
Si 5.928 5.931 5.742 5.777 5.584 5.847 5.808 5.742 Ti 0.562 0.568 0.681 0.658 0.742 0.639 0.663 0.691 Alƍᵛ 2.051 2.051 2.246 2.197 2.406 2.121 2.171 2.228 Al ᵛƍ 0.289 0.343 0.273 0.335 0.281 0.328 0.280 0.289 Cr 0.000 Mg 1.978 1.964 2.405 2.231 2.600 2.099 2.386 2.393 Ca 1.874 1.849 1.870 1.888 1.919 1.896 1.888 1.915 Mn 0.052 0.043 0.029 0.027 0.013 0.034 0.024 0.024 Fe³Ά 1.771 1.790 1.605 1.723 1.359 1.685 1.636 1.586 Fe²Ά 0.340 0.284 0.000 0.012 0.000 0.200 0.000 0.000 Na 0.774 0.756 0.713 0.689 0.659 0.715 0.680 0.692 K 0.256 0.239 0.244 0.262 0.215 0.226 0.253 0.241 Ni
Mg# 85.34 87.38 100.00 99.45 100.00 91.31 100.00 100.00 Structural formulae on the basis of 24 O. Spaces left blank denote no data was collected for that oxide/element 107
Electron Analysis Host: Amphibole MS113A-63 MS113A-62 MS113A-61 MS113A-60 MS113A-58 MS113A-57 MS113A-56 Ferri-PotassianTitanian Ferri-Potassian Ferri-Kaersutite Ferri-Kaersutite Ferri-Kaersutite Magnesiohastingsite Ferri-Kaersutite Ferri-Kaersutite Kaersutite Core Core Core Unidentified Rim Mantle Core SiO 37.89 38.37 38.46 38.14 37.69 38.43 38.20 TiO 6.62 6.09 5.73 3.33 6.23 5.60 5.02 AlOΎ 14.89 14.19 13.51 14.26 14.77 13.99 12.99 CrOΏ MgO 11.29 10.77 9.16 8.94 11.25 9.47 6.88 CaO 12.06 11.82 11.59 11.09 11.88 11.70 11.38 MnO 0.15 0.19 0.23 0.28 0.13 0.23 0.37 FeO 11.18 12.34 15.27 16.98 11.33 14.42 18.86 NaO 2.33 2.40 2.48 2.50 2.35 2.52 2.41 KO 1.15 1.16 1.28 1.48 1.20 1.17 1.34 NiO F 0.18 0.26 0.17 0.29 0.14 0.29 0.05 Cl 0.03 0.02 0.03 0.04 0.01 0.02 0.03 Total 97.78 97.60 97.89 97.32 96.98 97.83 97.54
Si 5.649 5.759 5.832 5.868 5.666 5.811 5.910 Ti 0.742 0.687 0.654 0.385 0.705 0.636 0.584 Alƍᵛ 2.320 2.214 2.139 2.180 2.312 2.157 2.062 Al ᵛƍ 0.310 0.308 0.287 0.383 0.315 0.350 0.318 Cr Mg 2.510 2.411 2.071 2.049 2.522 2.136 1.588 Ca 1.927 1.901 1.883 1.827 1.913 1.895 1.887 Mn 0.019 0.024 0.029 0.036 0.017 0.029 0.049 Fe³Ά 1.401 1.555 1.709 2.166 1.429 1.681 1.722 Fe²Ά 0.000 0.000 0.237 0.000 0.000 0.152 0.730 Na 0.674 0.699 0.728 0.747 0.685 0.739 0.723 K 0.218 0.221 0.247 0.290 0.230 0.226 0.265 Ni
Mg# 100.00 100.00 89.74 100.00 100.00 93.36 68.50 Structural formulae on the basis of 24 O. Spaces left blank denote no data was collected for that oxide/element 108 Electron Analysis Host: Amphibole MS113A-40 MS113A-39 MS113A-38 MS113A-37 MS113A-36 MS113A-35 MS113A-34 MS113A-33 Ferri-Potassian Ferri-Potassian Ferri-Potassian Ferri-Potassian Ferri-Potassian Kaersutite Kaersutite Ferri-Kaersutite Ferri-Kaersutite Kaersutite Ferri-Kaersutite Kaersutite Kaersutite Rim Mantle Core Unidentified Unidentified Rim Mantle Core SiO 38.29 38.61 37.98 38.69 38.13 37.98 38.65 38.43 TiO 6.03 5.45 5.97 5.51 6.00 5.77 5.68 4.97 AlOΎ 13.94 13.75 14.09 13.15 14.01 14.40 13.93 12.92 CrOΏ MgO 11.01 9.90 10.72 8.07 10.37 11.07 10.96 6.76 CaO 11.68 11.52 11.56 11.36 11.72 11.74 11.73 11.29 MnO 0.19 0.24 0.19 0.29 0.20 0.15 0.19 0.38 FeO 12.43 14.19 13.08 16.89 13.06 12.29 12.55 18.97 NaO 2.31 2.38 2.42 2.42 2.32 2.34 2.32 2.51 KO 1.33 1.34 1.28 1.27 1.31 1.28 1.31 1.40 NiO F 0.18 0.17 0.22 0.19 0.14 0.23 0.16 0.14 Cl 0.02 0.04 0.02 0.04 0.02 0.03 0.03 0.03 Total 97.39 97.60 97.54 97.87 97.28 97.28 97.50 97.80
Si 5.762 5.840 5.729 5.908 5.761 5.722 5.806 5.937 Ti 0.682 0.620 0.677 0.633 0.681 0.654 0.642 0.577 Alƍᵛ 2.226 2.146 2.269 2.063 2.216 2.272 2.180 2.029 Al ᵛƍ 0.251 0.311 0.237 0.314 0.289 0.287 0.292 0.336 Cr 0.000 0.000 0.000 Mg 2.470 2.233 2.410 1.837 2.334 2.487 2.454 1.558 Ca 1.883 1.866 1.868 1.858 1.897 1.896 1.888 1.869 Mn 0.024 0.031 0.025 0.037 0.025 0.019 0.024 0.050 Fe³Ά 1.567 1.799 1.650 1.709 1.657 1.550 1.581 1.676 Fe²Ά 0.000 0.000 0.000 0.458 0.000 0.000 0.000 0.789 Na 0.674 0.699 0.708 0.716 0.679 0.683 0.675 0.750 K 0.256 0.259 0.246 0.247 0.253 0.245 0.251 0.276 Ni
Mg# 100.00 100.00 100.00 80.05 100.00 100.00 100.00 66.37 Structural formulae on the basis of 24 O. Spaces left blank denote no data was collected for that oxide/element 109 Electron Analysis Host: Amphibole MB07-185A2_AR42 MB07-185A2_AC43 MB07-185A2_AC42 MB07-185A2_AC41B MB07-185A2_AC41 MB07-185A2_AC40B
Fluoro -Kaersutite Fluoro -Kaersutite Fluoro -Kaersutite Fluoro -Kaersutite Fluoro -Kaersutite Fluoro -Kaersutite Rim Core Core Core Core Core SiO 38.64 38.34 38.15 38.38 38.66 37.70 TiO 6.17 5.88 6.08 6.14 5.87 5.75 AlOΎ 14.23 14.22 14.10 14.13 14.08 13.52 MgO 12.75 10.15 9.93 11.33 11.42 9.59 CaO 12.40 11.85 11.77 12.15 12.02 11.60 MnO 0.12 0.19 0.19 0.15 0.19 0.23 FeO 10.00 13.97 14.15 12.30 12.49 15.82 NaO 2.75 2.65 2.76 2.91 2.53 2.85 KO 1.03 1.26 1.18 1.23 1.24 1.21 F 1.00 0.30 0.72 0.93 0.19 1.39 Cl 0.02 0.01 0.03 0.02 0.04 0.04 Total 99.10 98.83 99.07 99.67 98.74 99.69
Si 5.65 5.72 5.68 5.64 5.73 5.64 Ti 0.68 0.66 0.68 0.68 0.65 0.65 Alƍᵛ 2.26 2.24 2.24 2.26 2.24 2.28 Al ᵛƍ 0.23 0.28 0.27 0.23 0.23 0.14 Mg 2.78 2.26 2.20 2.48 2.53 2.14 Ca 1.94 1.89 1.88 1.91 1.91 1.86 Mn 0.01 0.02 0.02 0.02 0.02 0.03 Fe³Ά 0.00 0.00 0.00 0.00 0.00 0.00 Fe²Ά 1.24 1.76 1.79 1.54 1.56 2.01 Na 0.78 0.77 0.80 0.83 0.73 0.83 K 0.19 0.24 0.22 0.23 0.23 0.23
Mg# 69.11 56.25 55.25 61.78 61.88 51.55 Structural formulae on the basis of 23 O. Spaces left blank denote no data was collected for that oxide/element. 110 Electron Analysis Host: Amphibole MB07-185A2_AC40 MB07-184_AR51B MB07-184_AR51 MB07-184_AR50B MB07-184_AR50 MB07-184_AR39B MB07-184_AR39
Fluoro - Fluoro -Kaersutite PotassianKaersutite Fluoro -Kaersutite Fluoro -Kaersutite Fluoro -Kaersutite Fluoro -Kaersutite Fluoro -Kaersutite Core Rim Rim Rim Rim Rim Rim SiO 38.42 37.96 37.37 38.71 37.51 38.20 36.47 TiO 5.88 5.60 6.26 5.01 5.71 5.21 5.77 AlOΎ 13.68 13.15 13.93 12.56 13.05 14.44 14.28 MgO 9.37 11.50 11.95 11.33 11.68 11.45 12.19 CaO 11.86 11.68 11.86 11.77 11.90 10.96 11.12 MnO 0.28 0.21 0.14 0.24 0.16 0.17 0.09 FeO 15.55 12.71 11.40 13.10 12.31 11.60 8.85 NaO 2.69 2.47 2.39 2.72 2.36 2.35 2.25 KO 1.25 1.36 1.14 1.26 1.25 1.27 1.01 F 0.17 0.29 0.18 Cl 0.04 0.02 0.02 0.06 0.03 0.09 0.06 Total 99.18 96.66 96.46 96.77 95.95 96.02 92.28
Si 5.76 5.77 5.65 5.88 5.74 5.78 5.68 Ti 0.66 0.64 0.71 0.57 0.66 0.59 0.68 Alƍᵛ 2.20 2.24 2.35 2.10 2.27 2.23 2.31 Al ᵛƍ 0.23 0.12 0.13 0.15 0.09 0.34 0.32 Mg 2.09 2.61 2.70 2.57 2.66 2.58 2.83 Ca 1.90 1.90 1.92 1.92 1.95 1.78 1.86 Mn 0.04 0.03 0.02 0.03 0.02 0.02 0.01 Fe³Ά 0.00 0.05 0.03 0.00 0.03 0.22 0.03 Fe²Ά 1.96 1.56 1.41 1.67 1.55 1.24 1.12 Na 0.78 0.73 0.70 0.80 0.70 0.69 0.68 K 0.24 0.26 0.22 0.25 0.24 0.24 0.20
Mg# 51.63 62.48 65.61 60.60 63.24 67.52 71.61 Structural formulae on the basis of 23 O. Spaces left blank denote no data was collected for that oxide/element. 111 Electron Analysis Host: Amphibole MB07-184_AC51B MB07-184_AC51 MB07-184_AC50B MB07-184_AC50 MB07-184_AC39B MB07-184_AC39 MB07-184_AC38B Fluoro Titano - Potassian Fluoro Titano - Ferrokaersutite Ferrokaersutite Fluoro -Kaersutite Fluoro -Kaersutite Fluoro -Kaersutite Fluoro -Kaersutite Fluoro -Kaersutite Core Core Core Core Core Core Core SiO 37.96 38.00 38.06 35.65 38.16 36.42 38.34 TiO 5.42 5.64 6.01 6.24 4.89 5.00 5.98 AlOΎ 12.65 13.04 13.74 12.73 13.41 13.61 14.83 MgO 8.97 9.02 10.84 10.46 9.35 9.45 12.01 CaO 11.53 11.47 12.01 11.85 10.71 10.69 11.86 MnO 0.31 0.29 0.14 0.17 0.27 0.20 0.15 FeO 16.12 16.29 12.66 12.73 14.24 13.01 11.35 NaO 2.52 2.67 2.26 2.29 2.80 2.22 2.42 KO 1.35 1.26 1.21 1.21 1.26 1.16 1.30 F 0.22 0.17 0.23 Cl 0.04 0.02 0.03 0.04 0.09 0.23 0.03 Total 96.86 97.71 96.95 93.37 95.39 92.14 98.51
Si 5.85 5.81 5.75 5.64 5.90 6.06 5.66 Ti 0.63 0.65 0.68 0.74 0.57 0.63 0.66 Alƍᵛ 2.13 2.18 2.22 2.33 2.07 2.18 2.33 Al ᵛƍ 0.18 0.17 0.24 0.06 0.38 0.38 0.26 Mg 2.06 2.06 2.44 2.47 2.15 2.34 2.64 Ca 1.90 1.88 1.94 2.01 1.77 1.90 1.88 Mn 0.04 0.04 0.02 0.02 0.04 0.03 0.02 Fe³Ά 0.00 0.00 0.00 0.00 0.00 1.74 0.03 Fe²Ά 2.08 2.08 1.61 1.69 1.85 0.00 1.37 Na 0.75 0.79 0.66 0.70 0.84 0.72 0.69 K 0.27 0.24 0.23 0.24 0.25 0.25 0.25
Mg# 49.72 49.65 60.32 59.31 53.80 100.00 65.81 Structural formulae on the basis of 23 O. Spaces left blank denote no data was collected for that oxide/element. 112 Electron Analysis Host: Amphibole MB07-184_AC38 MB07-181_AR13 MB07-181_AR12B MB07-181_AR12 MB07-181_AR11 MB07-181_AR10 MB07-181_AOR10
Fluoro -Kaersutite Kaersutite Kaersutite Kaersutite PotassianKaersutite Kaersutite Fluoro -Kaersutite Core Rim Rim Rim Rim Rim Rim SiO 38.56 37.75 37.84 37.98 38.64 38.59 38.47 TiO 6.12 6.04 6.38 6.10 5.63 5.66 6.22 AlOΎ 14.65 14.74 14.23 14.05 14.10 13.62 14.46 MgO 11.95 11.58 11.37 11.35 11.31 9.15 12.48 CaO 12.17 11.87 11.66 11.61 11.56 11.60 12.12 MnO 0.12 0.15 0.18 0.16 0.18 0.25 0.13 FeO 11.52 11.76 12.20 12.78 13.17 15.34 10.10 NaO 2.37 2.39 2.41 2.39 2.42 2.63 2.43 KO 1.31 1.16 1.28 1.24 1.36 1.21 1.12 F 0.30 0.35 0.22 0.27 0.31 0.05 0.20 Cl 0.03 0.02 0.02 0.04 0.05 0.03 0.00 Total 99.11 97.81 97.77 97.96 98.73 98.14 97.73
Si 5.67 5.63 5.66 5.68 5.74 5.83 5.94 Ti 0.68 0.68 0.72 0.69 0.63 0.64 0.72 Alƍᵛ 2.30 2.35 2.33 2.32 2.26 2.14 2.27 Al ᵛƍ 0.25 0.25 0.19 0.16 0.21 0.30 0.26 Mg 2.62 2.57 2.54 2.53 2.50 2.06 2.87 Ca 1.92 1.90 1.87 1.86 1.84 1.88 2.00 Mn 0.02 0.02 0.02 0.02 0.02 0.03 0.02 Fe³Ά 0.00 0.02 0.01 0.13 0.16 0.00 1.26 Fe²Ά 1.42 1.45 1.52 1.47 1.48 1.95 0.00 Na 0.68 0.69 0.70 0.69 0.70 0.77 0.73 K 0.25 0.22 0.24 0.24 0.26 0.23 0.22
Mg# 64.78 64.01 62.56 63.30 62.92 51.40 100.00 Structural formulae on the basis of 23 O. Spaces left blank denote no data was collected for that oxide/element. 113 Electron Analysis Host: Amphibole MB07-181_AC13B MB07-181_AC13 MB07-181_AC12B MB07-181_AC12 MB07-181_AC11 MB07-181_AC10 MB07-180C_AR19B
Titano -Potassian Titano -Potassian Ferrokaersutite Ferrokaersutite Kaersutite Kaersutite Kaersutite Kaersutite Kaersutite Core Core Core Core Core Core Rim SiO 38.42 38.48 37.97 37.89 38.06 38.61 37.95 TiO 5.28 5.34 5.77 5.64 5.80 5.70 5.07 AlOΎ 13.05 13.00 13.85 14.07 13.93 13.62 14.07 MgO 8.27 8.14 9.73 9.55 10.88 9.18 10.75 CaO 11.39 11.38 11.67 11.60 11.71 11.56 11.64 MnO 0.30 0.34 0.26 0.23 0.16 0.24 0.22 FeO 17.52 17.44 14.90 15.18 13.36 15.13 13.38 NaO 2.58 2.44 2.50 2.56 2.24 2.51 2.59 KO 1.39 1.37 1.24 1.24 1.30 1.14 1.26 F 0.23 0.22 0.17 0.17 0.20 0.18 0.28 Cl 0.01 0.03 0.03 0.04 0.03 0.05 0.03 Total 98.44 98.17 98.09 98.16 97.67 97.93 97.24
Si 5.85 5.87 5.73 5.72 5.73 5.83 5.74 Ti 0.61 0.61 0.66 0.64 0.66 0.65 0.58 Alƍᵛ 2.12 2.10 2.25 2.26 2.27 2.13 2.25 Al ᵛƍ 0.23 0.25 0.22 0.25 0.20 0.31 0.27 Mg 1.88 1.85 2.19 2.15 2.44 2.07 2.42 Ca 1.86 1.86 1.89 1.88 1.89 1.87 1.89 Mn 0.04 0.04 0.03 0.03 0.02 0.03 0.03 Fe³Ά 0.00 0.00 0.00 0.00 0.08 0.00 0.04 Fe²Ά 2.24 2.24 1.89 1.92 1.60 1.92 1.66 Na 0.76 0.72 0.73 0.75 0.65 0.74 0.76 K 0.27 0.27 0.24 0.24 0.25 0.22 0.24
Mg# 45.60 45.30 53.73 52.80 60.36 51.79 59.38 Structural formulae on the basis of 23 O. Spaces left blank denote no data was collected for that oxide/element. 114 Electron Analysis Host: Amphibole MB07-180C_AR19 MB07-180C_AR18 MB07-180C_AOR19 MB07-180C_AC19B MB07-180C_AC19 MB07-180C_AC18 MB07-180C_AC17
Titano -Potassian Titano -Potassian Titano - Titano - Kaersutit Kaersutite Kaersutite Ferrokaersutite Ferrokaersutite Ferrokaersutite Ferrokaersutite Rim Rim Rim Core Core Core Core SiO 38.39 37.48 38.72 38.41 38.17 38.22 38.57 TiO 5.10 6.75 4.66 5.17 5.36 5.56 5.27 AlOΎ 14.14 15.06 12.98 12.85 13.17 13.91 13.28 MgO 11.01 12.04 10.30 7.69 7.99 8.53 7.47 CaO 11.70 12.01 11.38 11.39 11.35 11.54 11.40 MnO 0.23 0.12 0.24 0.36 0.32 0.34 0.34 FeO 12.97 11.08 14.55 17.75 17.38 16.25 18.33 NaO 2.72 2.20 2.65 2.44 2.44 2.52 2.46 KO 1.11 1.19 1.13 1.38 1.30 1.27 1.27 F 0.39 0.22 0.31 0.13 0.17 0.28 0.07 Cl 0.03 0.01 0.06 0.06 0.04 0.03 0.03 Total 97.78 98.16 97.00 97.65 97.68 98.45 98.50
Si 5.75 5.55 5.89 5.90 5.85 5.78 5.88 Ti 0.57 0.75 0.53 0.60 0.62 0.63 0.60 Alƍᵛ 2.22 2.44 2.10 2.06 2.12 2.18 2.10 Al ᵛƍ 0.29 0.19 0.24 0.28 0.27 0.32 0.30 Mg 2.46 2.66 2.34 1.76 1.83 1.92 1.70 Ca 1.88 1.91 1.85 1.88 1.86 1.87 1.86 Mn 0.03 0.02 0.03 0.05 0.04 0.04 0.04 Fe³Ά 0.00 0.06 0.07 0.00 0.00 0.00 0.00 Fe²Ά 1.63 1.31 1.79 2.30 2.24 2.07 2.35 Na 0.79 0.63 0.78 0.73 0.73 0.74 0.73 K 0.21 0.23 0.22 0.27 0.26 0.24 0.25
Mg# 60.13 66.99 56.70 43.43 44.94 48.17 41.99 Structural formulae on the basis of 23 O. Spaces left blank denote no data was collected for that oxide/element. 115 Electron Analysis Host: Amphibole MB07-174_T9 MB07-174_T8 MB07-174_T7 MB07-174_T6 MB07-174_T5 MB07-174_T4 MB07-174_T3 Fluoro Titano - Fluoro Titano - Fluoro - Fluoro -Potassian Fluoro -Potassian Potassian Potassian PotassianTitanian Ferropargasite Fluoro -Kaersutite Fluoro -Kaersutite Kaersutite Ferrokaersutite Ferrokaersutite Magnesiohastingsite Core Core Core Core Core Core Core SiO 38.36 38.44 37.79 37.81 37.38 37.59 37.74 TiO 4.17 5.64 5.34 4.93 4.41 4.40 3.98 AlOΎ 11.87 12.43 12.60 12.37 12.03 12.05 11.96 MgO 7.56 10.59 9.72 9.36 7.49 7.63 6.75 CaO 11.20 11.72 11.69 11.47 11.05 11.18 11.12 MnO 0.43 0.26 0.31 0.31 0.43 0.42 0.45 FeO 18.75 13.50 14.94 15.68 18.77 18.58 20.28 NaO 2.71 2.76 2.70 2.65 2.62 2.59 2.62 KO 1.35 1.08 1.25 1.34 1.40 1.37 1.43 F Cl 0.07 0.04 0.04 0.05 0.08 0.08 0.07 Total 96.47 96.46 96.39 95.97 95.65 95.90 96.39
Si 6.01 5.87 5.83 5.88 5.92 5.93 6.23 Ti 0.49 0.65 0.62 0.58 0.53 0.52 0.49 Alƍᵛ 1.98 2.09 2.15 2.11 2.08 2.07 2.03 Al ᵛƍ 0.22 0.16 0.16 0.16 0.16 0.17 0.19 Mg 1.77 2.41 2.24 2.17 1.77 1.79 1.66 Ca 1.88 1.92 1.93 1.91 1.87 1.89 1.97 Mn 0.06 0.03 0.04 0.04 0.06 0.06 0.06 Fe³Ά 0.00 0.00 0.00 0.00 0.03 0.00 1.95 Fe²Ά 2.46 1.73 1.94 2.04 2.45 2.45 0.73 Na 0.82 0.82 0.81 0.80 0.80 0.79 0.84 K 0.27 0.21 0.25 0.27 0.28 0.28 0.30
Mg# 41.78 58.18 53.60 51.50 41.90 42.25 69.54 Structural formulae on the basis of 23 O. Spaces left blank denote no data was collected for that oxide/element. 116 Electron Analysis Host: Amphibole MB07-174_T2 MB07-174_T15 MB07-174_T14 MB07-174_T13 MB07-174_T12 MB07-174_T11 MB07-174_T10 Fluoro - Fluoro - Fluoro - Fluoro - PotassianTitanian PotassianTitanian PotassianTitanian Fluoro -Potassian Fluoro -Potassian Fluoro -Potassian PotassianTitanian Ferropargasite Ferropargasite Ferropargasite Ferropargasite Kaersutite Kaersutite Ferropargasite Core Rim Core Core Core Core Core SiO 37.38 37.93 38.81 38.89 38.65 38.46 38.38 TiO 3.47 3.24 3.98 4.24 4.91 5.11 4.01 AlOΎ 11.52 12.60 12.18 12.34 12.78 12.20 11.88 MgO 5.66 5.13 6.68 7.67 9.21 9.12 7.28 CaO 11.11 10.27 10.90 11.26 11.41 11.30 11.13 MnO 0.58 0.47 0.44 0.45 0.35 0.33 0.50 FeO 21.79 20.13 20.17 18.58 15.97 15.72 19.38 NaO 2.41 6.09 2.55 2.62 2.67 2.64 2.57 KO 1.54 1.55 1.43 1.39 1.29 1.28 1.43 F Cl 0.08 0.04 0.06 0.08 0.04 0.05 0.06 Total 95.54 97.44 97.21 97.51 97.28 96.22 96.61
Si 6.02 5.98 6.05 6.01 5.91 5.95 6.02 Ti 0.42 0.38 0.47 0.49 0.57 0.59 0.47 Alƍᵛ 1.98 1.84 1.95 1.98 2.07 2.03 1.98 Al ᵛƍ 0.21 0.57 0.29 0.27 0.24 0.21 0.22 Mg 1.36 1.21 1.55 1.77 2.10 2.10 1.70 Ca 1.92 1.74 1.82 1.86 1.87 1.87 1.87 Mn 0.08 0.06 0.06 0.06 0.04 0.04 0.07 Fe³Ά 0.03 0.00 0.03 0.00 0.00 0.00 0.01 Fe²Ά 2.90 2.73 2.60 2.41 2.05 2.04 2.53 Na 0.75 1.86 0.77 0.78 0.79 0.79 0.78 K 0.32 0.31 0.29 0.27 0.25 0.25 0.29
Mg# 31.90 30.62 37.38 42.33 50.66 50.73 40.17 Structural formulae on the basis of 23 O. Spaces left blank denote no data was collected for that oxide/element. 117 Electron Analysis Host: Amphibole MB07-174_T1 MB07-174_B-T9 MB07-174_B-T8 MB07-174_B-T7 MB07-174_B-T6 MB07-174_B-T5 MB07-174_B-T4 Fluoro - Fluoro - Fluoro Titano - Fluoro - Fluoro - Fluoro Titano - PotassianTitanian PotassianTitanian Fluoro -Potassian Potassian PotassianTitanian PotassianTitanian Potassian Ferropargasite Ferropargasite Ferropargasite Ferrokaersutite Ferropargasite Ferropargasite Ferrokaersutite Rim Core Core Core Core Core Core SiO 36.19 38.19 38.42 38.42 38.51 38.21 38.58 TiO 3.63 3.55 4.23 4.49 3.29 4.07 4.34 AlOΎ 10.24 11.66 12.20 12.15 12.65 12.52 12.28 MgO 5.81 5.94 7.82 8.30 8.01 8.11 8.11 CaO 11.42 11.06 11.49 11.32 11.16 11.38 11.38 MnO 0.48 0.49 0.42 0.43 0.46 0.45 0.38 FeO 21.66 21.81 18.47 17.63 18.64 18.13 17.65 NaO 3.00 2.54 2.62 2.67 2.68 2.61 2.64 KO 1.20 1.62 1.39 1.32 1.45 1.37 1.42 F Cl 0.01 0.08 0.08 0.06 0.08 0.05 0.03 Total 93.65 96.95 97.14 96.80 96.94 96.90 96.82
Si 5.99 6.05 5.97 5.96 5.99 5.94 5.99 Ti 0.45 0.42 0.49 0.52 0.39 0.48 0.51 Alƍᵛ 1.98 1.95 2.01 2.03 2.03 2.06 1.99 Al ᵛƍ 0.03 0.22 0.23 0.20 0.29 0.23 0.26 Mg 1.43 1.40 1.81 1.92 1.86 1.88 1.88 Ca 2.02 1.88 1.91 1.88 1.86 1.90 1.89 Mn 0.07 0.07 0.06 0.06 0.06 0.06 0.05 Fe³Ά 0.00 0.03 0.00 0.00 0.17 0.03 0.00 Fe²Ά 3.01 2.86 2.41 2.29 2.24 2.33 2.30 Na 0.96 0.78 0.79 0.80 0.81 0.79 0.80 K 0.25 0.33 0.27 0.26 0.29 0.27 0.28
Mg# 32.24 32.92 42.95 45.57 45.30 44.71 44.93 Structural formulae on the basis of 23 O. Spaces left blank denote no data was collected for that oxide/element. 118 Electron Analysis Host: Amphibole MB07-174_B-T3 MB07-174_B-T2 MB07-174_B-T10 MB07-174_B-T1 MB07-174_AR9 MB07-174_AR8 MB07-174_AR7 Fluoro - Fluoro - Fluoro - Fluoro - PotassianTitanian PotassianTitanian PotassianTitanian PotassianTitanian PotassianTitanian PotassianTitanian PotassianTitanian Ferropargasite Ferropargasite Ferropargasite Ferropargasite Ferropargasite Ferropargasite Ferropargasite Core Core Rim Rim Rim Rim Rim SiO 37.92 37.76 36.60 37.85 38.29 38.54 38.25 TiO 3.69 3.55 3.71 3.98 3.68 3.58 4.00 AlOΎ 11.70 11.64 10.17 11.94 12.16 12.52 12.54 MgO 6.07 5.91 5.58 6.88 5.99 5.53 7.51 CaO 11.09 11.08 11.03 11.18 11.00 10.65 11.24 MnO 0.54 0.51 0.45 0.49 0.51 0.48 0.45 FeO 21.37 21.88 20.30 20.50 21.99 20.13 19.05 NaO 2.60 2.45 4.45 2.58 2.38 6.19 2.66 KO 1.58 1.59 1.29 1.45 1.54 1.44 1.45 F 0.27 0.23 0.26 Cl 0.08 0.08 0.10 0.09 0.08 0.02 0.07 Total 96.64 96.45 93.68 96.94 97.88 99.32 97.48
Si 6.02 6.02 6.04 5.96 5.99 5.96 5.94 Ti 0.44 0.43 0.46 0.47 0.43 0.42 0.47 Alƍᵛ 1.98 1.99 1.83 2.05 2.01 1.85 2.05 AAl ᵛƍ 0.21 0.19 0.20 0.16 0.23 0.50 0.25 Mg 1.44 1.40 1.37 1.61 1.40 1.27 1.74 Ca 1.89 1.89 1.95 1.89 1.84 1.76 1.87 Mn 0.07 0.07 0.06 0.07 0.07 0.06 0.06 Fe³Ά 0.00 0.09 0.00 0.11 0.21 0.00 0.02 Fe²Ά 2.84 2.82 2.86 2.58 2.67 2.69 2.46 Na 0.80 0.76 1.42 0.79 0.72 1.85 0.80 K 0.32 0.32 0.27 0.29 0.31 0.28 0.29
Mg# 33.59 33.22 32.40 38.46 34.38 32.19 41.43 Structural formulae on the basis of 23 O. Spaces left blank denote no data was collected for that oxide/element. 119 Electron Analysis Host: Amphibole MB07-174_AR6 MB07-174_AOR9 MB07-174_AOR7 MB07-174_AC9 MB07-174_AC8 MB07-174_AC7 MB07-174_AC6
PotassianTitanian PotassianTitanian PotassianTitanian Potassian PotassianTitanian PotassianTitanian Ferropargasite Ferropargasite Ferropargasite Ferropargasite Ferropargasite Kaersutite Ferropargasite Rim Rim Rim Core Core Core Core SiO 38.20 37.70 38.31 39.00 38.22 39.35 38.56 TiO 3.75 4.05 3.43 4.28 3.47 5.19 4.04 AlOΎ 12.12 12.23 12.96 12.91 12.48 12.81 13.25 MgO 5.87 6.39 5.04 8.15 5.54 9.67 7.63 CaO 10.98 10.63 10.47 11.23 10.77 11.51 11.21 MnO 0.52 0.45 0.45 0.40 0.46 0.30 0.44 FeO 22.15 20.11 19.78 18.27 21.00 14.89 18.76 NaO 2.44 4.16 6.61 2.66 6.56 2.88 2.75 KO 1.55 1.64 1.48 1.30 1.50 1.24 1.41 F 0.33 0.12 0.23 0.39 0.06 0.27 0.27 Cl 0.05 0.01 0.02 0.08 0.03 0.04 0.08 Total 97.96 97.49 98.78 98.68 100.09 98.15 98.42
Si 5.98 5.92 5.95 5.93 5.90 5.93 5.91 Ti 0.44 0.48 0.40 0.49 0.40 0.59 0.47 Alƍᵛ 2.02 2.01 1.82 2.05 1.92 2.01 2.08 AAl ᵛƍ 0.22 0.27 0.64 0.27 0.42 0.28 0.32 Mg 1.37 1.49 1.17 1.85 1.28 2.17 1.74 Ca 1.84 1.79 1.74 1.83 1.78 1.86 1.84 Mn 0.07 0.06 0.06 0.05 0.06 0.04 0.06 Fe³Ά 0.18 0.00 0.00 0.09 0.00 0.00 0.04 Fe²Ά 2.72 2.67 2.67 2.24 2.79 1.89 2.37 Na 0.74 1.27 1.99 0.79 1.97 0.84 0.82 K 0.31 0.33 0.29 0.25 0.29 0.24 0.28
Mg# 33.48 35.88 30.41 45.18 31.37 53.41 42.36 Structural formulae on the basis of 23 O. Spaces left blank denote no data was collected for that oxide/element. 120 Electron Analysis Host: Amphibole MB07- MB07-174_A11Cd MB07-174_A11Cc MB07-174_A11Cb MB07-174_A11C MB07-174_A10Cd 174 AC5 FluorianPotassianTitanian PotassianTitanian PotassianTitanian PotassianTitanian PotassianTitanian Ferropargasite Ferropargasite Ferropargasite Kaersutite Ferropargasite Ferropargasite Core Core Core Core Core Core SiO 38.66 38.53 39.12 38.90 39.01 39.01 TiO 3.70 3.67 4.19 5.17 4.01 3.65 AlOΎ 12.14 11.76 11.91 12.49 11.99 10.36 MgO 5.70 5.68 7.62 9.38 7.48 7.15 CaO 10.90 11.20 11.26 11.54 11.28 11.42 MnO 0.55 0.53 0.42 0.33 0.46 0.45 FeO 21.78 22.58 18.94 15.49 19.05 19.23 NaO 2.87 2.44 2.56 2.69 2.56 3.38 KO 1.51 1.63 1.45 1.27 1.44 2.10 F 0.61 Cl 0.09 0.07 0.06 0.04 0.06 0.04 Total 98.49 98.10 97.52 97.29 97.35 96.78
Si 6.01 6.04 6.05 5.94 6.05 6.15 Ti 0.43 0.43 0.49 0.59 0.47 0.43 Alƍᵛ 1.94 1.96 1.94 2.03 1.94 1.74 AAl ᵛƍ 0.30 0.21 0.24 0.23 0.26 0.21 Mg 1.32 1.33 1.76 2.14 1.73 1.68 Ca 1.81 1.88 1.87 1.89 1.87 1.93 Mn 0.07 0.07 0.05 0.04 0.06 0.06 Fe³Ά 0.00 0.06 0.00 0.00 0.00 0.00 Fe²Ά 2.86 2.90 2.46 1.99 2.48 2.58 Na 0.87 0.74 0.77 0.79 0.77 1.03 K 0.30 0.33 0.29 0.25 0.29 0.42
Mg# 31.63 31.42 41.70 51.80 41.13 39.45 Structural formulae on the basis of 23 O. Spaces left blank denote no data was collected for that oxide/element. 121 Electron Analysis Host: Amphibole MB07-174_A10Cc MB07-174_A10Cb MB07-174_A10C MB07-167_A9Cb MB07-167_A9C MB07-167_A8Rb MB07-167_A8R
PotassianTitanian Titano -Potassian PotassianTitanian Ferropargasite Ferrokaersutite Ferropargasite Kaersutite Kaersutite Kaersutite Kaersutite Core Core Core Core Core Rim Rim SiO 39.13 38.84 38.54 38.58 38.06 38.35 38.25 TiO 3.80 4.43 3.22 6.41 6.04 6.83 6.36 AlOΎ 11.96 12.18 12.86 13.77 14.01 13.87 13.69 MgO 6.92 7.86 8.03 11.76 11.31 12.55 11.14 CaO 11.22 11.24 11.06 11.93 11.93 12.39 11.93 MnO 0.46 0.42 0.41 0.17 0.18 0.14 0.17 FeO 20.39 18.29 18.49 11.32 12.49 10.38 12.50 NaO 2.50 2.57 2.55 2.74 2.72 2.33 2.66 KO 1.42 1.32 1.40 1.16 1.12 1.17 1.17 F Cl 0.08 0.10 0.25 0.03 0.01 0.01 0.04 Total 97.88 97.23 96.81 97.88 97.87 98.02 97.91
Si 6.07 6.01 5.99 5.74 5.70 5.68 5.73 Ti 0.44 0.52 0.38 0.72 0.68 0.76 0.72 Alƍᵛ 1.93 1.98 2.03 2.22 2.28 2.29 2.24 Al ᵛƍ 0.25 0.24 0.32 0.21 0.20 0.14 0.19 Mg 1.60 1.81 1.86 2.61 2.52 2.77 2.49 Ca 1.86 1.86 1.84 1.90 1.91 1.97 1.91 Mn 0.06 0.05 0.05 0.02 0.02 0.02 0.02 Fe³Ά 0.03 0.00 0.24 0.00 0.00 0.00 0.00 Fe²Ά 2.61 2.37 2.16 1.42 1.57 1.29 1.57 Na 0.75 0.77 0.77 0.79 0.79 0.67 0.77 K 0.28 0.26 0.28 0.22 0.21 0.22 0.22
Mg# 38.03 43.34 46.33 64.80 61.68 68.21 61.26 Structural formulae on the basis of 23 O. Spaces left blank denote no data was collected for that oxide/element. 122 Electron Analysis Host: Amphibole MB07-167_A8Cb MB07-167_A8C MB07-145_AR55B MB07-145_AR55 MB07-145_AR54B MB07-145_AR54 MB07-145_AR53B
Fluoro -Potassian Kaersutite Kaersutite Fluoro -Kaersutite Fluoro -Kaersutite Fluoro -Kaersutite Fluoro -Kaersutite Kaersutite Core Core Rim Rim Rim Rim Rim SiO 38.03 38.26 37.93 37.96 35.85 36.09 36.53 TiO 6.35 6.21 5.21 5.60 6.48 6.25 6.52 AlOΎ 14.06 13.86 12.64 13.40 14.17 14.17 14.31 MgO 11.68 11.13 10.00 11.65 11.58 12.08 12.68 CaO 12.28 11.88 11.46 11.97 11.80 11.68 12.22 MnO 0.11 0.17 0.25 0.16 0.14 0.15 0.12 FeO 11.44 12.34 14.60 12.15 11.72 10.90 10.56 NaO 2.52 2.45 2.71 2.58 2.49 2.62 2.26 KO 1.18 1.22 1.11 1.14 1.25 1.14 1.30 F Cl 0.03 0.01 0.05 0.02 0.04 0.04 0.02 Total 97.69 97.53 95.95 96.63 95.51 95.13 96.52
Si 5.68 5.74 5.85 5.75 5.51 5.54 5.52 Ti 0.71 0.70 0.60 0.64 0.75 0.72 0.74 Alƍᵛ 2.28 2.24 2.13 2.24 2.49 2.46 2.49 Al ᵛƍ 0.21 0.22 0.17 0.16 0.07 0.10 0.06 Mg 2.60 2.49 2.30 2.63 2.65 2.77 2.86 Ca 1.97 1.91 1.89 1.94 1.94 1.92 1.98 Mn 0.01 0.02 0.03 0.02 0.02 0.02 0.02 Fe³Ά 0.00 0.00 0.00 0.00 0.05 0.08 0.09 Fe²Ά 1.44 1.55 1.89 1.54 1.46 1.32 1.25 Na 0.73 0.71 0.81 0.76 0.74 0.78 0.66 K 0.23 0.23 0.22 0.22 0.25 0.22 0.25
Mg# 64.39 61.55 54.93 63.05 64.52 67.77 69.63 Structural formulae on the basis of 23 O. Spaces left blank denote no data was collected for that oxide/element. 123 Electron Analysis Host: Amphibole MB07-145_AR53 MB07-145_AR3B MB07-145_AR3 MB07-145_AR2B MB07-145_AR2 MB07-145_AC55B MB07-145_AC55
Fluoro -Kaersutite Kaersutite Kaersutite Kaersutite Kaersutite Fluoro -Kaersutite Fluoro -Kaersutite Rim Rim Rim Rim Rim Core Core SiO 36.89 37.58 37.21 38.72 36.80 37.49 38.39 TiO 6.39 6.56 6.43 6.02 6.42 5.30 5.21 AlOΎ 14.45 14.52 14.55 14.04 14.71 12.58 12.77 MgO 12.63 11.18 11.73 12.51 12.05 9.91 9.83 CaO 11.95 11.85 11.98 11.91 11.76 11.37 11.50 MnO 0.14 0.17 0.16 0.13 0.16 0.25 0.30 FeO 10.34 12.17 11.54 10.61 11.21 14.79 15.21 NaO 2.25 2.50 2.48 2.38 2.41 2.75 2.63 KO 1.23 1.20 1.14 1.09 1.10 1.14 1.12 F 0.24 0.19 0.18 0.27 Cl 0.03 0.02 0.02 0.01 0.01 0.06 0.04 Total 96.30 97.99 97.43 97.61 96.91 95.62 97.00
Si 5.57 5.61 5.58 5.75 5.54 5.82 5.87 Ti 0.73 0.74 0.73 0.67 0.73 0.62 0.60 Alƍᵛ 2.44 2.36 2.41 2.24 2.47 2.17 2.13 Al ᵛƍ 0.12 0.21 0.17 0.22 0.14 0.13 0.17 Mg 2.84 2.49 2.62 2.77 2.70 2.29 2.24 Ca 1.93 1.90 1.92 1.89 1.90 1.89 1.88 Mn 0.02 0.02 0.02 0.02 0.02 0.03 0.04 Fe³Ά 0.13 0.00 0.00 0.00 0.17 0.00 0.00 Fe²Ά 1.18 1.53 1.45 1.32 1.24 1.92 1.95 Na 0.66 0.73 0.72 0.68 0.70 0.83 0.78 K 0.24 0.23 0.22 0.21 0.21 0.23 0.22
Mg# 70.73 61.97 64.39 67.71 68.60 54.40 53.51 Structural formulae on the basis of 23 O. Spaces left blank denote no data was collected for that oxide/element. 124 Electron Analysis Host: Amphibole MB07-145_AC54B MB07-145_AC54 MB07-145_AC53C MB07-145_AC53B MB07-145_AC53 MB07-145_AC4B MB07-145_AC4
Fluoro -Kaersutite Fluoro -Kaersutite Fluoro -Kaersutite Fluoro -Kaersutite Fluoro -Kaersutite Kaersutite Kaersutite Core Core Core Core Core Core Core SiO 37.10 37.44 37.05 36.66 38.03 38.18 38.73 TiO 5.55 5.63 6.32 5.76 5.86 5.73 5.29 AlOΎ 12.82 12.74 13.99 13.41 13.48 13.46 12.97 MgO 10.60 10.45 11.41 10.82 11.02 10.07 10.06 CaO 11.62 11.49 11.89 11.65 11.82 11.37 11.48 MnO 0.23 0.25 0.18 0.21 0.18 0.26 0.30 FeO 13.84 13.89 12.10 13.48 13.29 14.23 14.98 NaO 2.50 2.63 2.35 2.51 2.56 2.54 2.81 KO 1.04 1.15 1.26 1.23 1.18 1.18 1.10 F 0.14 0.20 Cl 0.05 0.04 0.00 0.04 0.03 0.02 0.05 Total 95.34 95.72 96.55 95.76 97.44 97.16 97.97
Si 5.75 5.78 5.63 5.66 5.74 5.80 5.85 Ti 0.65 0.65 0.72 0.67 0.67 0.65 0.60 Alƍᵛ 2.26 2.21 2.37 2.35 2.25 2.19 2.13 Al ᵛƍ 0.08 0.11 0.13 0.08 0.15 0.22 0.19 Mg 2.45 2.41 2.58 2.49 2.48 2.28 2.27 Ca 1.93 1.90 1.93 1.93 1.91 1.85 1.86 Mn 0.03 0.03 0.02 0.03 0.02 0.03 0.04 Fe³Ά 0.06 0.00 0.00 0.09 0.00 0.00 0.00 Fe²Ά 1.73 1.79 1.54 1.64 1.68 1.81 1.90 Na 0.75 0.79 0.69 0.75 0.75 0.75 0.82 K 0.20 0.23 0.24 0.24 0.23 0.23 0.21
Mg# 58.63 57.29 62.71 60.25 59.64 55.74 54.41 Structural formulae on the basis of 23 O. Spaces left blank denote no data was collected for that oxide/element. 125 Electron Analysis Host: Amphibole MB07-145_AC3B MB07-145_AC3 MB07-145_AC2B MB07-145_AC2 MB07-145_AC1 MB07-134_A4R MB07-134_A4Cb
Titano - Titano -Potassian Titano -Potassian Ferrokaersutite Kaersutite Kaersutite Kaersutite Kaersutite Ferrokaersutite Ferrokaersutite Core Core Core Core Core Rim Core SiO 38.38 38.10 38.79 38.56 37.39 37.08 37.23 TiO 5.61 5.67 5.48 5.49 6.33 4.50 4.49 AlOΎ 12.92 12.90 13.23 13.08 14.19 10.47 10.65 MgO 8.67 8.98 10.48 10.44 10.94 5.27 5.15 CaO 11.33 11.55 11.46 11.52 11.83 10.40 10.42 MnO 0.32 0.32 0.24 0.26 0.18 1.08 1.14 FeO 16.57 16.00 13.78 13.91 12.65 23.30 23.35 NaO 2.62 2.57 2.60 2.70 2.51 2.55 2.54 KO 1.23 1.17 1.12 1.11 1.27 1.39 1.48 F 0.20 0.19 0.13 0.30 0.06 Cl 0.06 0.05 0.05 0.05 0.01 0.10 0.06 Total 97.91 97.51 97.34 97.40 97.35 96.13 96.52
Si 5.85 5.82 5.86 6.09 5.64 5.99 6.00 Ti 0.64 0.65 0.62 0.65 0.72 0.55 0.54 Alƍᵛ 2.12 2.15 2.13 2.14 2.34 1.98 2.01 Al ᵛƍ 0.21 0.19 0.24 0.21 0.19 0.00 0.00 Mg 1.97 2.04 2.36 2.46 2.46 1.27 1.24 Ca 1.85 1.89 1.85 1.95 1.91 1.80 1.80 Mn 0.04 0.04 0.03 0.03 0.02 0.15 0.16 Fe³Ά 0.00 0.00 0.00 1.77 0.00 0.39 0.35 Fe²Ά 2.12 2.06 1.74 0.00 1.60 2.74 2.77 Na 0.77 0.76 0.76 0.83 0.73 0.80 0.79 K 0.24 0.23 0.22 0.22 0.24 0.29 0.30
Mg# 48.13 49.86 57.49 100.00 60.59 31.69 30.81 Structural formulae on the basis of 23 O. Spaces left blank denote no data was collected for that oxide/element. 126 Electron Analysis Host: Amphibole MB07-134_A4C MB07-134_A3Rb MB07-134_A3R MB07-134_A3Cb MB07-134_A2C MB07-134_A1C MB07-114_AR59B Fluoro - Titano -Potassian Titano - Titano - PotassianTitanian Titano -Potassian Ferrokaersutite Kaersutite Ferrokaersutite Ferrokaersutite Ferropargasite Ferrokaersutite Fluoro -Kaersutite Core Rim Rim Core Core Core Rim SiO 37.72 37.14 37.19 37.35 36.79 36.32 35.48 TiO 4.54 5.78 5.30 5.33 4.74 4.63 6.06 AlOΎ 10.41 12.99 12.03 11.93 10.93 10.77 13.25 MgO 5.35 10.77 8.20 7.85 5.23 4.98 11.28 CaO 10.50 11.43 10.98 10.88 10.56 10.64 11.48 MnO 1.09 0.72 0.84 0.83 1.19 1.19 0.71 FeO 23.23 13.94 17.90 18.81 23.30 23.61 12.85 NaO 2.57 2.41 2.43 2.49 2.44 2.47 2.28 KO 1.43 1.11 1.19 1.23 1.54 1.45 1.15 F Cl 0.10 0.04 0.05 0.07 0.10 0.08 0.03 Total 96.94 96.33 96.12 96.77 96.81 96.12 94.57
Si 6.04 5.71 5.84 5.85 6.17 5.90 5.55 Ti 0.55 0.67 0.63 0.63 0.60 0.57 0.71 Alƍᵛ 1.95 2.33 2.19 2.19 2.05 2.04 2.42 Al ᵛƍ 0.00 0.01 0.02 0.00 0.00 0.00 0.00 Mg 1.28 2.47 1.92 1.83 1.31 1.21 2.63 Ca 1.80 1.88 1.85 1.83 1.90 1.85 1.92 Mn 0.15 0.09 0.11 0.11 0.17 0.16 0.09 Fe³Ά 0.30 0.32 0.28 0.32 2.28 0.38 0.43 Fe²Ά 2.79 1.47 2.05 2.13 0.83 2.80 1.24 Na 0.80 0.72 0.74 0.76 0.79 0.78 0.69 K 0.29 0.22 0.24 0.25 0.33 0.30 0.23
Mg# 31.40 62.75 48.31 46.25 61.31 30.14 67.98 Structural formulae on the basis of 23 O. Spaces left blank denote no data was collected for that oxide/element. 127 Electron Analysis Host: Amphibole MB07-114_AR59 MB07-114_AR58 MB07-114_ACC57B MB07-114_ACC57 MB07-114_ACC56B MB07-114_ACC56 MB07-114_AC61B Fluoro Titano - Fluoro Titano - Fluoro Titano - Fluoro Titano - Potassian Potassian Potassian Potassian Titano - Fluoro -Kaersutite Fluoro -Kaersutite Ferrokaersutite Ferrokaersutite Ferrokaersutite Ferrokaersutite Ferrokaersutite Rim Rim Core Core Core Core Core SiO 35.19 36.21 37.08 36.98 37.09 35.24 36.30 TiO 5.76 6.37 4.60 4.76 4.50 4.61 5.38 AlOΎ 12.99 13.78 10.96 11.44 11.02 9.78 12.46 MgO 10.66 12.03 6.51 7.08 5.85 5.82 7.95 CaO 11.10 11.76 10.78 10.77 10.70 10.86 11.08 MnO 0.78 0.60 0.97 0.93 1.06 1.03 0.85 FeO 13.87 11.39 21.01 19.88 22.20 21.13 17.96 NaO 2.42 2.16 2.45 2.53 2.50 2.36 2.47 KO 1.13 1.20 1.49 1.34 1.55 1.56 1.18 F Cl 0.05 0.02 0.08 0.08 0.08 0.08 0.06 Total 93.96 95.52 95.93 95.78 96.57 92.48 95.68
Si 5.58 5.56 5.94 5.90 5.94 5.92 5.74 Ti 0.69 0.74 0.55 0.57 0.54 0.58 0.64 Alƍᵛ 2.40 2.48 2.06 2.14 2.07 1.93 2.29 Al ᵛƍ 0.00 0.00 0.00 0.00 0.00 0.00 0.02 Mg 2.52 2.75 1.55 1.68 1.40 1.46 1.88 Ca 1.88 1.94 1.85 1.84 1.84 1.96 1.88 Mn 0.11 0.08 0.13 0.13 0.14 0.15 0.11 Fe³Ά 0.52 0.29 0.27 0.29 0.31 0.06 0.27 Fe²Ά 1.29 1.16 2.53 2.34 2.65 2.91 2.10 Na 0.74 0.64 0.76 0.78 0.78 0.77 0.76 K 0.23 0.24 0.31 0.27 0.32 0.33 0.24
Mg# 66.05 70.29 38.04 41.81 34.55 33.39 47.24 Structural formulae on the basis of 23 O. Spaces left blank denote no data was collected for that oxide/element. 128 Electron Analysis Host: Amphibole MB07-114_AC61 MB07-114_AC60 MB07-114_AC59 MB07-114_AC58 MB07-028_A7R MB07-028_A7C MB07-028_A6Cc Alumino Fluoro Potassic - Fluoro -Kaersutite Ferroedenite Fluoro -Kaersutite Fluoro -Kaersutite Kaersutite Kaersutite Kaersutite Core Core Core Core Rim Core Core SiO 36.92 36.42 35.33 36.55 37.26 37.81 36.70 TiO 5.14 4.27 5.44 5.80 5.74 5.43 5.54 AlOΎ 11.77 10.59 12.45 12.81 12.35 11.73 11.96 MgO 8.77 5.50 8.43 9.37 10.91 10.17 10.62 CaO 11.09 10.62 11.27 11.48 11.19 11.14 11.28 MnO 0.81 1.17 0.86 0.70 0.85 0.89 0.87 FeO 16.84 22.88 16.86 15.39 13.71 15.35 14.17 NaO 2.69 2.50 2.38 2.37 2.41 2.35 2.51 KO 1.17 1.64 1.22 1.17 1.01 0.97 0.99 F Cl 0.06 0.07 0.03 0.04 0.03 0.05 0.06 Total 95.26 95.67 94.29 95.70 95.46 95.89 94.70
Si 5.84 5.93 5.66 5.71 5.77 5.87 5.76 Ti 0.61 0.52 0.66 0.68 0.67 0.63 0.65 Alƍᵛ 2.18 2.02 2.34 2.31 2.24 2.13 2.20 Al ᵛƍ 0.00 0.00 0.00 0.05 0.00 0.00 0.00 Mg 2.07 1.34 2.02 2.18 2.52 2.35 2.49 Ca 1.88 1.85 1.94 1.92 1.86 1.85 1.90 Mn 0.11 0.16 0.12 0.09 0.11 0.12 0.12 Fe³Ά 0.16 0.37 0.24 0.12 0.38 0.41 0.33 Fe²Ά 2.06 2.72 2.01 1.88 1.38 1.57 1.51 Na 0.82 0.79 0.74 0.72 0.72 0.71 0.76 K 0.24 0.34 0.25 0.23 0.20 0.19 0.20
Mg# 50.09 32.89 50.10 53.66 64.54 60.05 62.16 Structural formulae on the basis of 23 O. Spaces left blank denote no data was collected for that oxide/element. 129 Electron Analysis Host: Amphibole MB07-028_A6Cb MB07-028_A6C MB07-028_A5Rb MB07-028_A5R MB07-028_A5Cb MB07-028_A5C MB07-025_A15R
Kaersutite Kaersutite Kaersutite Kaersutite Kaersutite Kaersutite Fluoro -Kaersutite Core Core Rim Rim Core Core Rim SiO 37.30 37.38 37.22 36.84 37.32 37.36 38.16 TiO 5.51 5.44 5.58 6.06 5.05 5.21 5.89 AlOΎ 11.73 11.78 12.00 12.63 11.62 11.53 13.55 MgO 10.31 10.38 11.41 11.59 9.16 9.11 9.92 CaO 11.20 11.16 11.36 11.68 10.75 10.97 11.66 MnO 0.95 0.94 0.82 0.81 1.02 1.00 0.24 FeO 15.09 15.14 13.07 12.61 17.03 16.99 14.39 NaO 2.51 2.43 2.27 2.29 2.46 2.44 2.85 KO 1.03 0.92 0.95 1.00 0.97 0.97 1.22 F Cl 0.05 0.05 0.06 0.04 0.05 0.06 0.05 Total 95.68 95.62 94.75 95.54 95.43 95.63 97.94
Si 5.82 5.82 5.79 5.69 5.88 5.87 5.77 Ti 0.65 0.64 0.65 0.70 0.60 0.62 0.67 Alƍᵛ 2.14 2.14 2.18 2.28 2.13 2.12 2.20 Al ᵛƍ 0.00 0.00 0.00 0.00 0.00 0.00 0.22 Mg 2.40 2.41 2.65 2.67 2.15 2.13 2.23 Ca 1.87 1.86 1.90 1.93 1.81 1.85 1.89 Mn 0.13 0.12 0.11 0.11 0.14 0.13 0.03 Fe³Ά 0.37 0.47 0.40 0.31 0.55 0.44 0.00 Fe²Ά 1.58 1.48 1.29 1.31 1.66 1.77 1.83 Na 0.76 0.73 0.69 0.69 0.75 0.74 0.83 K 0.20 0.18 0.19 0.20 0.19 0.19 0.24
Mg# 60.31 61.90 67.24 67.06 56.41 54.63 55.00 Structural formulae on the basis of 23 O. Spaces left blank denote no data was collected for that oxide/element. 130 Electron Analysis Host: Amphibole MB07-025_A15C MB07-025_A14Cb MB07-025_A14C MB07-017_AR57 MB07-017_AR56 MB07-017_AR15 MB07-017_AC57B
Fluoro -Kaersutite Fluoro -Kaersutite Kaersutite Fluoro -Kaersutite Fluoro -Kaersutite Kaersutite Fluoro -Kaersutite Core Core Core Rim Rim Rim Core SiO 38.79 38.90 39.20 37.64 37.85 38.21 37.28 TiO 5.64 4.94 5.11 6.25 5.72 6.71 6.30 AlOΎ 13.65 13.06 13.26 12.87 12.53 14.55 13.49 MgO 10.19 11.28 11.21 12.40 10.97 12.75 11.92 CaO 11.42 11.41 11.36 11.96 11.47 12.26 11.69 MnO 0.21 0.18 0.23 0.40 0.49 0.12 0.45 FeO 14.36 13.28 13.22 10.97 13.37 10.14 11.96 NaO 2.84 2.88 2.92 2.43 2.51 2.26 2.37 KO 1.06 1.05 1.07 1.10 1.16 1.03 1.13 F 0.25 Cl 0.03 0.03 0.03 0.05 0.04 0.02 0.03 Total 98.19 97.03 97.62 96.06 96.12 98.30 96.61
Si 5.82 5.88 5.88 5.72 5.81 5.63 5.66 Ti 0.64 0.56 0.58 0.71 0.66 0.74 0.72 Alƍᵛ 2.17 2.13 2.12 2.28 2.20 2.35 2.37 Al ᵛƍ 0.25 0.20 0.23 0.03 0.06 0.18 0.03 Mg 2.28 2.54 2.51 2.81 2.51 2.80 2.70 Ca 1.84 1.85 1.83 1.95 1.89 1.93 1.90 Mn 0.03 0.02 0.03 0.05 0.06 0.01 0.06 Fe³Ά 0.00 0.06 0.03 0.00 0.09 0.00 0.21 Fe²Ά 1.80 1.61 1.63 1.40 1.62 1.25 1.30 Na 0.83 0.85 0.85 0.71 0.75 0.64 0.70 K 0.20 0.20 0.20 0.21 0.23 0.19 0.22
Mg# 55.82 61.16 60.65 66.81 60.74 69.09 67.46 Structural formulae on the basis of 23 O. Spaces left blank denote no data was collected for that oxide/element. 131 Electron Analysis Host: Amphibole MB07-017_AC57 MB07-017_AC56C MB07-017_AC56B MB07-017_AC56 MB07-017_AC16 MB07-017_AC15 MB06-832_AR21
PotassianTitanian Fluoro -Kaersutite Fluoro -Kaersutite Fluoro -Kaersutite Fluoro -Kaersutite Kaersutite Kaersutite Ferropargasite Core Core Core Core Core Core Rim SiO 35.07 36.80 37.22 37.50 38.34 38.60 32.74 TiO 6.39 5.83 5.94 5.89 6.72 6.32 3.25 AlOΎ 12.07 12.46 12.63 12.72 14.57 13.41 11.83 MgO 11.18 10.99 11.16 10.82 12.45 11.54 5.33 CaO 12.09 11.73 11.74 11.69 12.13 11.58 8.54 MnO 0.42 0.47 0.46 0.47 0.10 0.18 0.42 FeO 10.97 13.28 13.07 13.26 9.94 12.44 15.36 NaO 2.15 2.38 2.40 2.33 2.43 2.65 5.51 KO 1.17 1.18 1.17 1.20 1.20 1.15 1.15 F 0.15 0.30 0.28 Cl 0.05 0.05 0.05 0.06 0.03 0.03 0.06 Total 91.55 95.17 95.84 95.94 98.05 98.22 84.48
Si 5.64 5.72 5.73 5.77 5.66 5.75 5.88 Ti 0.77 0.68 0.69 0.68 0.75 0.71 0.44 Alƍᵛ 2.30 2.28 2.28 2.23 2.31 2.23 1.94 Al ᵛƍ 0.00 0.00 0.01 0.07 0.24 0.14 0.64 Mg 2.68 2.55 2.56 2.48 2.74 2.56 1.43 Ca 2.08 1.95 1.94 1.93 1.92 1.85 1.64 Mn 0.06 0.06 0.06 0.06 0.01 0.02 0.06 Fe³Ά 0.00 0.09 0.07 0.02 0.00 0.00 0.00 Fe²Ά 1.48 1.64 1.61 1.69 1.23 1.56 2.38 Na 0.67 0.72 0.72 0.69 0.69 0.77 1.92 K 0.24 0.23 0.23 0.24 0.23 0.22 0.26
Mg# 64.34 60.89 61.47 59.52 68.94 62.23 37.49 Structural formulae on the basis of 23 O. Spaces left blank denote no data was collected for that oxide/element. 132 Electron Analysis Host: Amphibole MB06-832_AC22B MB06-832_AC22 MB06-832_AC21 MB06-832_AC20B MB06-832_AC20 MB06-827_A13Cb
FerrianPotassianTitanian Titano -Potassian Titano -Potassian PotassianKaersutite PotassianKaersutite Magnesiosadanagaite Ferrokaersutite Ferrokaersutite Kaersutite Core Core Core Core Core Core SiO 36.69 35.52 28.94 36.62 36.42 39.54 TiO 4.42 5.14 3.13 4.24 3.93 5.62 AlOΎ 12.03 12.27 11.96 11.62 11.53 12.30 MgO 7.96 8.99 7.61 7.35 6.90 10.89 CaO 9.80 9.72 8.80 9.60 9.51 11.84 MnO 0.34 0.25 0.37 0.32 0.34 0.29 FeO 13.95 11.58 14.78 14.44 15.37 14.24 NaO 2.46 2.32 2.43 2.59 2.44 2.56 KO 1.25 1.22 1.50 1.29 1.32 1.24 F 0.28 0.31 0.79 0.17 0.32 Cl 0.05 0.05 0.42 0.05 0.05 0.02 Total 89.22 87.36 80.72 88.28 88.13 98.54
Si 6.06 5.93 5.45 6.13 6.14 5.92 Ti 0.55 0.65 0.44 0.53 0.50 0.63 Alƍᵛ 1.89 2.01 2.58 1.80 1.80 2.07 Al ᵛƍ 0.48 0.42 0.06 0.52 0.51 0.11 Mg 1.96 2.24 2.14 1.83 1.73 2.43 Ca 1.73 1.74 1.78 1.72 1.72 1.90 Mn 0.05 0.04 0.06 0.04 0.05 0.04 Fe³Ά 0.00 0.00 0.86 0.00 0.00 0.00 Fe²Ά 1.94 1.63 1.46 2.04 2.19 1.79 Na 0.79 0.75 0.89 0.84 0.80 0.74 K 0.26 0.26 0.36 0.28 0.28 0.24
Mg# 50.20 57.85 59.47 47.30 44.20 57.65 Structural formulae on the basis of 23 O. Spaces left blank denote no data was collected for that oxide/element. 133 Electron Analysis Host: Amphibole MB06-827_A13C MB06-827_A12C MB06-508_AR52B MB06-508_AR44 MB06-508_AC52B MB06-508_AC52 MB06-508_AC46B
Fluoro -Potassian Kaersutite Kaersutite Fluoro -Kaersutite Kaersutite Fluoro -Kaersutite Fluoro -Kaersutite Fluoro -Kaersutite Core Core Rim Rim Core Core Core SiO 39.22 38.06 38.70 39.71 39.54 38.77 39.21 TiO 5.93 6.64 6.50 6.33 6.30 6.78 6.84 AlOΎ 13.09 14.27 12.17 13.33 13.17 12.24 12.78 MgO 11.39 11.90 11.35 10.72 11.74 11.56 11.32 CaO 11.80 11.94 11.50 11.26 11.27 11.80 11.55 MnO 0.21 0.13 0.26 0.26 0.24 0.26 0.24 FeO 12.88 11.10 11.97 12.36 12.02 11.97 12.08 NaO 2.50 2.50 2.50 2.66 2.61 2.42 2.65 KO 1.20 1.16 1.26 1.45 1.29 1.23 1.25 F 0.43 0.23 Cl 0.01 0.02 0.04 0.04 0.07 0.05 0.05 Total 98.23 97.73 96.24 98.54 98.25 97.07 98.20
Si 5.85 5.67 5.88 5.88 6.12 5.84 5.83 Ti 0.67 0.74 0.74 0.71 0.73 0.77 0.77 Alƍᵛ 2.14 2.31 2.09 2.05 2.13 2.12 2.11 Al ᵛƍ 0.16 0.20 0.11 0.31 0.18 0.06 0.15 Mg 2.53 2.64 2.57 2.37 2.71 2.60 2.51 Ca 1.89 1.90 1.87 1.79 1.87 1.90 1.84 Mn 0.03 0.02 0.03 0.03 0.03 0.03 0.03 Fe³Ά 0.00 0.00 0.00 0.00 1.49 0.00 0.00 Fe²Ά 1.61 1.39 1.53 1.55 0.00 1.52 1.52 Na 0.72 0.72 0.74 0.76 0.78 0.71 0.76 K 0.23 0.22 0.24 0.27 0.25 0.24 0.24
Mg# 61.15 65.58 62.69 60.43 100.00 63.11 62.35 Structural formulae on the basis of 23 O. Spaces left blank denote no data was collected for that oxide/element. 134
Electron Analysis Host: Amphibole MB06-508_AC46 MB06-508_AC45B MB06-508_AC45 MB06-508_AC44
Fluoro -Kaersutite Fluoro -Kaersutite Fluoro -Kaersutite Fluoro -Kaersutite Core Core Core Core SiO 39.54 39.45 39.46 39.10 TiO 7.01 6.73 6.88 6.75 AlOΎ 12.94 12.45 12.78 12.82 MgO 11.37 11.55 11.44 11.20 CaO 11.58 11.74 11.66 11.60 MnO 0.24 0.23 0.22 0.27 FeO 12.19 11.70 12.03 12.29 NaO 2.59 2.53 2.57 2.50 KO 1.21 1.21 1.21 1.21 F 0.43 0.38 0.35 0.41 Cl 0.05 0.03 0.05 0.05 Total 99.16 98.00 98.64 98.20
Si 5.82 5.87 5.84 5.82 Ti 0.78 0.75 0.77 0.76 Alƍᵛ 2.12 2.06 2.10 2.12 Al ᵛƍ 0.15 0.15 0.15 0.15 Mg 2.49 2.56 2.52 2.49 Ca 1.83 1.87 1.85 1.85 Mn 0.03 0.03 0.03 0.03 Fe³Ά 0.00 0.00 0.00 0.00 Fe²Ά 1.52 1.47 1.50 1.54 Na 0.74 0.73 0.74 0.72 K 0.23 0.23 0.23 0.23
Mg# 62.19 63.49 62.66 61.68 Structural formulae on the basis of 23 O. Spaces left blank denote no data was collected for that oxide/element. 135 Electron Analysis Host: Clinopyroxene MS169N2-71 MS169N2-68 MS169N2-58 MS169N2-57 MS169N2-45 MS169N2-29 MS169N2-28 MS169N2-27 MS169N2-24 Diopside Diopside Diopside Diopside Diopside Hedenburgite Diopside Diopside Diopside Unidentified Unidentified Unidentified Unidentified Unidentified Unidentified Unidentified Unidentified Unidentified SiO 47.87 45.64 48.25 49.04 44.54 48.71 46.50 48.38 38.40 TiO 2.05 2.86 2.29 1.72 3.19 0.52 2.46 1.90 6.51 AlOΎ 5.62 8.54 6.61 5.20 8.95 2.57 7.88 5.65 14.10 CrOΏ MgO 11.33 10.70 13.52 12.29 10.42 5.37 11.20 11.99 8.40 CaO 21.70 22.05 21.45 22.30 22.11 20.85 22.21 21.94 21.34 MnO 0.27 0.20 0.18 0.25 0.23 1.26 0.24 0.28 0.18 FeO 10.72 9.35 7.86 8.85 9.66 19.46 8.93 9.39 10.06 NaO 0.47 0.69 0.46 0.55 0.70 1.22 0.66 0.56 0.81 KO 0.00 0.00 0.01 0.00 0.01 0.06 0.00 0.01 0.02 NiO F 0.03 0.00 0.12 0.12 0.00 0.05 0.08 0.02 0.06 Cl 0.00 0.00 0.00 0.01 0.00 0.00 0.00 0.00 0.00 Total 100.05 100.03 100.74 100.33 99.81 100.07 100.16 100.12 99.88
Si 1.802 1.710 1.779 1.827 1.675 1.906 1.737 1.808 1.457 Ti 0.058 0.081 0.063 0.048 0.090 0.015 0.069 0.053 0.186 Alƍᵛ 0.198 0.290 0.221 0.173 0.325 0.093 0.263 0.192 0.543 Al ᵛƍ 0.051 0.087 0.066 0.056 0.072 0.025 0.084 0.057 0.087 Cr Mg 0.636 0.598 0.743 0.683 0.584 0.313 0.624 0.668 0.475 Ca 0.875 0.885 0.847 0.890 0.891 0.874 0.889 0.878 0.867 Mn 0.009 0.006 0.006 0.008 0.007 0.042 0.008 0.009 0.006 Fe³Ά 0.272 0.201 0.181 0.215 0.181 0.130 0.089 0.068 0.144 Fe²Ά 0.065 0.092 0.062 0.061 0.123 0.507 0.191 0.225 0.175 Na 0.034 0.050 0.033 0.040 0.051 0.092 0.048 0.041 0.060 K 0.000 0.000 0.000 0.000 0.000 0.003 0.000 0.000 0.001
Mg# 90.67 86.71 92.34 91.85 82.63 38.20 76.60 74.81 73.07
End-members Wo 56 56 51 54 56 52 52 50 57 En 40 38 45 42 37 18 37 38 31 Fs 4 6 4 4 8 30 11 13 12 Structural formulae on the basis of 6 O. Spaces left blank denote no data was collected for that oxide/element. 136 Electron Analysis Host: Clinopyroxene MS169N2-20 MS169N2-19 MS169N2-14 MS169N2-13 MS169N2-12 MS169N2-08 MS169D-75 MS169D-68 MS169D-67 MS169D-62 Diopside Diopside Diopside Diopside Diopside Diopside Diopside Diopside Diopside Diopside Unidentified Unidentified Unidentified Unidentified Unidentified Unidentified Unidentified Unidentified Unidentified Unidentified SiO 47.14 45.93 40.71 42.31 49.41 48.54 44.37 39.52 46.63 44.07 TiO 2.53 2.89 5.09 4.48 1.70 2.00 3.10 5.63 2.24 3.16 AlOΎ 7.11 8.52 12.93 11.39 5.23 6.45 8.75 13.48 6.76 10.20 CrOΏ MgO 12.35 11.09 9.66 9.72 12.56 13.53 10.46 9.59 13.38 11.66 CaO 21.41 22.07 21.59 21.36 21.93 21.73 22.23 22.15 22.24 22.75 MnO 0.25 0.20 0.15 0.20 0.25 0.15 0.22 0.14 0.10 0.16 FeO 8.96 9.01 8.98 9.51 8.77 7.18 9.01 8.66 6.84 7.23 NaO 0.49 0.66 0.67 0.71 0.56 0.46 0.66 0.64 0.46 0.55 KO 0.03 0.01 0.00 0.00 0.02 0.00 0.00 0.01 0.00 0.00 NiO F 0.00 0.03 0.06 0.08 0.08 0.08 0.00 0.00 0.01 0.00 Cl 0.01 0.00 0.00 0.01 0.00 0.00 0.01 0.00 0.00 0.01 Total 100.27 100.40 99.83 99.77 100.50 100.11 98.80 99.81 98.65 99.78
Si 1.755 1.712 1.533 1.597 1.835 1.796 1.683 1.488 1.747 1.640 Ti 0.071 0.081 0.144 0.127 0.047 0.056 0.089 0.159 0.063 0.088 Alƍᵛ 0.245 0.288 0.467 0.403 0.165 0.204 0.317 0.513 0.251 0.360 Al ᵛƍ 0.067 0.086 0.107 0.104 0.064 0.077 0.075 0.086 0.044 0.088 Cr Mg 0.686 0.616 0.542 0.547 0.695 0.746 0.591 0.538 0.747 0.647 Ca 0.854 0.881 0.871 0.864 0.872 0.861 0.904 0.893 0.893 0.907 Mn 0.008 0.006 0.005 0.007 0.008 0.005 0.007 0.004 0.003 0.005 Fe³Ά 0.071 0.087 0.122 0.097 0.046 0.049 0.173 0.118 0.100 0.090 Fe²Ά 0.208 0.194 0.161 0.203 0.226 0.173 0.113 0.155 0.114 0.135 Na 0.035 0.048 0.049 0.052 0.040 0.033 0.049 0.046 0.033 0.040 K 0.001 0.000 0.000 0.000 0.001 0.000 0.000 0.001 0.000 0.000
Mg# 76.73 76.07 77.08 72.90 75.46 81.15 83.92 77.64 86.75 82.77
End-members Wo 49 52 55 54 49 48 56 56 51 54 En 39 36 34 34 39 42 37 34 43 38 Fs 12 11 10 13 13 10 7 10 7 8 Structural formulae on the basis of 6 O. Spaces left blank denote no data was collected for that oxide/element. 137 Electron Analysis Host: Clinopyroxene MS169D-61 MS169D-60 MS169D-54 MS169D-52 MS169D-46 MS169D-45 MS169D-43 MS169D-38 MS169D-37 MS169D-32 Hedenbergite Diopside Diopside Diopside Diopside Diopside Diopside Diopside Hedenburgite Diopside Unidentified Unidentified Unidentified Unidentified Unidentified Unidentified Unidentified Unidentified Unidentified Unidentified SiO 48.95 48.18 46.56 46.72 43.36 41.20 43.54 46.31 48.01 48.50 TiO 0.53 1.55 2.01 2.11 3.28 4.40 3.13 2.06 0.57 1.12 AlOΎ 2.48 5.19 6.51 6.20 10.38 11.28 8.79 6.41 2.40 3.47 CrOΏ MgO 7.36 12.74 12.50 13.96 11.48 10.55 9.98 11.72 6.75 11.70 CaO 21.59 22.40 22.20 21.80 22.49 22.13 22.14 22.62 21.87 22.54 MnO 0.78 0.26 0.25 0.14 0.14 0.16 0.29 0.26 0.72 0.36 FeO 17.00 8.23 8.76 7.07 7.65 8.47 9.74 8.81 17.70 9.90 NaO 0.71 0.57 0.59 0.47 0.55 0.61 0.72 0.56 0.62 0.52 KO 0.01 0.01 0.01 0.03 0.02 0.01 0.00 0.00 0.00 0.00 NiO F 0.03 0.06 0.02 0.08 0.00 0.00 0.00 0.01 0.05 0.07 Cl 0.01 0.00 0.00 0.01 0.01 0.00 0.01 0.00 0.00 0.02 Total 99.44 99.19 99.39 98.59 99.36 98.79 98.34 98.79 98.70 98.19
Si 1.908 1.807 1.743 1.751 1.623 1.560 1.664 1.751 1.894 1.855 Ti 0.016 0.044 0.057 0.060 0.092 0.125 0.090 0.059 0.017 0.032 Alƍᵛ 0.092 0.193 0.257 0.249 0.377 0.440 0.336 0.249 0.106 0.146 Al ᵛƍ 0.022 0.036 0.030 0.025 0.081 0.063 0.060 0.036 0.006 0.011 Cr Mg 0.428 0.712 0.698 0.780 0.641 0.595 0.569 0.661 0.397 0.667 Ca 0.902 0.900 0.890 0.875 0.902 0.898 0.907 0.916 0.924 0.924 Mn 0.026 0.008 0.008 0.005 0.004 0.005 0.009 0.008 0.024 0.012 Fe³Ά 0.461 0.147 0.118 0.082 0.089 0.098 0.163 0.137 0.113 0.109 Fe²Ά 0.093 0.111 0.156 0.139 0.151 0.171 0.148 0.141 0.471 0.208 Na 0.054 0.041 0.043 0.034 0.040 0.045 0.053 0.041 0.048 0.039 K 0.000 0.001 0.001 0.001 0.001 0.000 0.000 0.000 0.000 0.000
Mg# 82.14 86.53 81.71 84.87 80.96 77.72 79.31 82.38 45.74 76.24
End-members Wo 63 52 51 49 53 54 56 53 52 51 En 30 41 40 43 38 36 35 38 22 37 Fs 7 6 9 8 9 10 9 8 26 12 Structural formulae on the basis of 6 O. Spaces left blank denote no data was collected for that oxide/element. 138 Electron Analysis Host: Clinopyroxene MS169D-31 MS169D-30 MS169D-29 MS169D-26 MS169D-25 MS169D-22 MS169D-18 MS169D-17 MS169D-14 MS169D-13 Diopside Diopside Diopside Diopside Hedenburgite Diopside Diopside Diopside Diopside Diopside Unidentified Unidentified Unidentified Unidentified Unidentified Unidentified Rim Core Rim Mantle SiO 44.47 42.96 42.38 43.24 48.07 44.80 47.00 46.90 44.03 39.83 TiO 2.67 3.54 3.90 3.19 0.60 2.57 1.78 2.33 2.83 5.00 AlOΎ 7.49 9.51 9.77 9.60 2.24 8.39 6.08 6.70 9.05 12.91 CrOΏ MgO 12.06 10.79 10.57 10.39 7.56 11.08 12.43 13.50 10.98 9.51 CaO 22.38 22.30 22.13 22.09 22.20 22.58 22.69 22.57 22.20 22.13 MnO 0.19 0.19 0.16 0.19 0.90 0.22 0.27 0.17 0.23 0.17 FeO 8.57 8.75 9.11 9.25 16.04 8.94 8.63 7.03 9.07 9.15 NaO 0.54 0.68 0.63 0.69 0.67 0.73 0.61 0.45 0.68 0.74 KO 0.01 0.03 0.04 0.05 0.03 0.03 0.01 0.00 0.01 0.01 NiO F 0.29 0.00 0.07 0.01 0.03 0.11 0.07 0.00 0.08 0.07 Cl 0.01 0.02 0.00 0.00 0.00 0.01 0.01 0.02 0.01 0.00 Total 98.68 98.77 98.75 98.71 98.32 99.45 99.57 99.65 99.15 99.53
Si 1.684 1.627 1.610 1.642 1.892 1.684 1.757 1.741 1.660 1.504 Ti 0.076 0.101 0.111 0.091 0.018 0.073 0.050 0.065 0.080 0.142 Alƍᵛ 0.316 0.373 0.390 0.358 0.104 0.316 0.243 0.259 0.340 0.496 Al ᵛƍ 0.018 0.052 0.048 0.072 0.000 0.056 0.025 0.034 0.063 0.079 Cr Mg 0.681 0.609 0.599 0.588 0.444 0.621 0.693 0.747 0.617 0.535 Ca 0.908 0.905 0.901 0.898 0.937 0.909 0.909 0.898 0.897 0.895 Mn 0.006 0.006 0.005 0.006 0.030 0.007 0.009 0.005 0.007 0.005 Fe³Ά 0.185 0.169 0.165 0.155 0.120 0.168 0.161 0.127 0.166 0.187 Fe²Ά 0.086 0.108 0.124 0.138 0.409 0.113 0.109 0.091 0.120 0.102 Na 0.039 0.050 0.046 0.051 0.051 0.053 0.044 0.033 0.049 0.054 K 0.001 0.001 0.002 0.002 0.001 0.001 0.000 0.000 0.001 0.000
Mg# 88.80 84.94 82.81 80.95 52.06 84.59 86.43 89.11 83.74 84.04
End-members Wo 54 56 55 55 52 55 53 52 55 58 En 41 38 37 36 25 38 41 43 38 35 Fs 5 7 8 9 23 7 6 5 7 7 Structural formulae on the basis of 6 O. Spaces left blank denote no data was collected for that oxide/element. 139 Electron Analysis Host: Clinopyroxene MS169D-12 MS169D-11 MS169D-03 MS169D-02 MS169D-01 MS169C-40 MS169C-37 MS169C-35 MS169C-33 MS169C-32 Diopside Diopside Diopside Diopside Diopside Diopside Diopside Diopside Diopside Diopside Core Core Rim Rim Core Unidentified Unidentified Unidentified Rim Rim SiO 40.32 46.53 50.39 46.57 43.85 50.04 45.37 45.42 45.35 42.91 TiO 4.49 2.39 0.93 2.14 3.51 1.00 2.81 2.56 3.08 4.10 AlOΎ 12.77 6.87 3.28 6.60 10.49 2.92 8.32 8.45 7.99 10.24 CrOΏ 0.00 0.00 0.01 0.02 0.17 MgO 10.46 13.08 11.43 13.76 11.76 11.95 11.08 10.81 10.63 11.08 CaO 22.51 22.33 22.87 22.47 22.63 22.52 22.47 22.24 22.05 22.49 MnO 0.11 0.16 0.48 0.14 0.14 0.42 0.21 0.23 0.29 0.11 FeO 7.92 7.44 10.57 6.77 7.00 10.51 8.98 9.53 9.64 7.60 NaO 0.58 0.45 0.51 0.47 0.63 0.46 0.65 0.65 0.73 0.54 KO 0.00 0.00 0.04 0.00 0.00 0.03 0.02 0.01 NiO 0.00 0.02 0.00 0.01 0.04 F 0.17 0.00 0.04 1.18 0.01 0.31 0.10 0.10 Cl 0.00 0.01 0.00 0.02 0.02 0.00 0.01 0.00 Total 99.34 99.25 100.54 100.11 100.03 100.14 100.04 100.02 99.79 99.27
Si 1.517 1.738 1.888 1.737 1.627 1.885 1.699 1.703 1.700 1.615 Ti 0.127 0.067 0.026 0.060 0.098 0.028 0.079 0.072 0.087 0.116 Alƍᵛ 0.483 0.262 0.112 0.263 0.373 0.115 0.301 0.297 0.293 0.385 Al ᵛƍ 0.084 0.041 0.033 0.027 0.085 0.014 0.066 0.077 0.061 0.069 Cr 0.000 0.000 0.000 0.001 0.005 Mg 0.587 0.729 0.639 0.765 0.650 0.671 0.618 0.604 0.594 0.621 Ca 0.907 0.894 0.918 0.898 0.899 0.908 0.901 0.893 0.885 0.907 Mn 0.004 0.005 0.015 0.004 0.004 0.013 0.007 0.007 0.009 0.004 Fe³Ά 0.187 0.119 0.063 0.150 0.137 0.078 0.124 0.123 0.173 0.108 Fe²Ά 0.062 0.113 0.269 0.062 0.080 0.253 0.157 0.176 0.123 0.132 Na 0.043 0.033 0.037 0.034 0.045 0.034 0.047 0.047 0.053 0.039 K 0.000 0.000 0.002 0.000 0.000 0.001 0.001 0.001
Mg# 90.45 86.57 70.40 92.53 89.04 72.62 79.73 77.46 82.89 82.46
End-members Wo 58 51 50 52 55 50 54 53 55 55 En 38 42 35 44 40 37 37 36 37 37 Fs 4 7 15 4 5 14 9 11 8 8 Structural formulae on the basis of 6 O. Spaces left blank denote no data was collected for that oxide/element. 140 Electron Analysis Host: Clinopyroxene MS169C-31 MS169C-30 MS169C-29 MS169C-28 MS169C-21 MS169C-18 MS169C-17 MS169C-16 MS169C-15 MS169C-13 Diopside Hedenburgite Hedenburgite Diopside Diopside Diopside Diopside Diopside Diopside Diopside Rim Core Core Unidentified Unidentified Rim Mantle Mantle Core Rim SiO 43.46 49.64 49.20 41.44 50.07 50.48 49.91 48.93 42.30 46.73 TiO 3.93 0.52 0.69 5.00 1.18 0.70 1.04 1.58 4.36 2.21 AlOΎ 9.98 2.62 2.98 11.18 3.75 2.63 3.49 4.93 10.69 6.68 CrOΏ 0.21 0.00 0.03 0.04 0.02 0.00 0.00 0.00 0.01 0.00 MgO 11.30 7.92 8.13 10.00 13.13 11.20 11.23 12.73 9.78 10.06 CaO 22.52 21.67 21.38 21.95 21.61 21.69 22.41 22.18 22.00 22.23 MnO 0.12 0.64 0.59 0.12 0.30 0.56 0.46 0.26 0.22 0.40 FeO 7.62 16.86 16.31 9.37 9.56 10.46 10.85 8.71 9.88 11.06 NaO 0.52 0.64 0.67 1.06 0.60 0.55 0.74 0.75 KO 0.04 0.01 0.00 0.03 0.03 NiO 0.00 0.01 0.00 0.00 0.03 0.00 0.00 0.00 0.00 0.01 F 0.32 0.00 0.08 0.09 0.13 Cl 0.00 0.00 0.00 0.01 0.01 Total 99.67 100.52 99.96 99.11 99.63 99.14 99.98 99.94 100.10 100.31
Si 1.627 1.868 1.859 1.582 1.883 1.917 1.881 1.825 1.593 1.761 Ti 0.111 0.015 0.020 0.144 0.033 0.020 0.029 0.044 0.123 0.063 Alƍᵛ 0.372 0.091 0.103 0.418 0.117 0.083 0.120 0.175 0.407 0.239 Al ᵛƍ 0.068 0.028 0.033 0.085 0.049 0.035 0.035 0.042 0.067 0.058 Cr 0.006 0.000 0.001 0.001 0.001 0.000 0.000 0.000 0.000 0.000 Mg 0.631 0.444 0.458 0.569 0.736 0.634 0.631 0.708 0.549 0.565 Ca 0.903 0.874 0.865 0.898 0.870 0.882 0.904 0.886 0.887 0.897 Mn 0.004 0.020 0.019 0.004 0.010 0.018 0.015 0.008 0.007 0.013 Fe³Ά 0.112 0.406 0.394 0.044 0.001 0.086 0.069 0.084 0.146 0.110 Fe²Ά 0.127 0.088 0.086 0.255 0.300 0.246 0.272 0.187 0.165 0.239 Na 0.038 0.047 0.049 0.078 0.044 0.039 0.054 0.055 K 0.000 0.000 0.002 0.000 0.000 0.001 0.001
Mg# 83.26 83.40 84.15 69.07 71.05 72.01 69.85 79.06 76.92 70.32
End-members Wo 54 62 61 52 46 50 50 50 55 53 En 38 32 32 33 39 36 35 40 34 33 Fs 8 6 6 15 16 14 15 11 10 14 Structural formulae on the basis of 6 O. Spaces left blank denote no data was collected for that oxide/element. 141 Electron Analysis Host: Clinopyroxene MS169C-12 MS169C-11 MS169C-05 MS169B1-58e MS169B1-58d MS169B1-58c MS169B1-58b MS169B1-58a MS169B1-56 Diopside Diopside Diopside Diopside Diopside Diopside Diopside Diopside Diopside Core Core Unidentified Rim Rim Mantle Mantle Core Unidentified SiO 45.20 42.52 45.21 41.19 41.37 41.43 41.57 41.63 45.61 TiO 2.83 4.21 2.74 4.58 4.58 4.56 4.56 4.57 2.96 AlOΎ 8.36 10.48 8.45 12.72 12.69 12.85 12.79 12.89 8.45 CrOΏ 0.01 0.03 0.00 0.17 0.20 0.22 0.22 0.24 0.00 MgO 10.92 10.07 10.66 10.60 10.99 10.43 10.40 10.57 10.96 CaO 22.22 21.53 21.81 22.03 21.89 22.11 22.07 22.39 22.53 MnO 0.23 0.21 0.27 0.10 0.11 0.10 0.11 0.12 0.23 FeO 9.18 9.40 9.85 8.10 7.92 8.09 8.04 7.96 9.54 NaO 0.67 0.75 0.76 0.56 0.55 0.57 0.53 0.54 0.67 KO 0.02 0.01 0.06 0.01 0.00 0.00 0.03 0.00 0.00 NiO 0.01 0.02 0.01 0.01 0.02 0.01 0.03 0.01 0.01 F 0.13 0.34 0.32 0.09 0.33 0.00 0.15 0.16 0.11 Cl 0.00 0.02 0.01 0.00 0.00 0.00 0.00 0.00 0.02 Total 99.77 99.58 100.14 100.15 100.63 100.36 100.49 101.09 101.07
Si 1.698 1.610 1.699 1.537 1.538 1.543 1.550 1.551 1.693 Ti 0.080 0.120 0.077 0.129 0.128 0.128 0.128 0.128 0.083 Alƍᵛ 0.302 0.390 0.301 0.462 0.461 0.457 0.449 0.458 0.307 Al ᵛƍ 0.069 0.078 0.073 0.098 0.095 0.108 0.113 0.105 0.063 Cr 0.000 0.001 0.000 0.005 0.006 0.007 0.006 0.007 0.000 Mg 0.612 0.568 0.597 0.590 0.609 0.579 0.578 0.587 0.607 Ca 0.894 0.873 0.878 0.881 0.872 0.882 0.881 0.894 0.896 Mn 0.007 0.007 0.009 0.003 0.004 0.003 0.004 0.004 0.007 Fe³Ά 0.121 0.126 0.128 0.142 0.144 0.128 0.112 0.056 0.127 Fe²Ά 0.167 0.171 0.182 0.111 0.102 0.124 0.138 0.192 0.170 Na 0.049 0.055 0.056 0.041 0.039 0.041 0.038 0.039 0.048 K 0.001 0.000 0.003 0.000 0.000 0.000 0.001 0.000 0.000
Mg# 78.54 76.85 76.64 84.15 85.62 82.36 80.71 75.34 78.16
End-members Wo 53 54 53 56 55 56 55 53 54 En 37 35 36 37 38 37 36 35 36 Fs 10 11 11 7 6 8 9 11 10 Structural formulae on the basis of 6 O. Spaces left blank denote no data was collected for that oxide/element. 142 Electron Analysis Host: Clinopyroxene MS169B1-48 MS169B1-35 MS169B1-26 MS169B1-23 MS169B1-22 MS169B1-18 MS169B1-17 MS169B1-15 MS169B1-14 Diopside Diopside Diopside Diopside Diopside Diopside Diopside Diopside Diopside Unidentified Unidentified Unidentified Core Rim Rim Core Unidentified Unidentified SiO 45.05 46.27 46.13 53.07 49.34 51.50 52.36 49.26 45.75 TiO 3.13 2.29 3.00 0.42 1.26 1.04 0.88 1.70 2.80 AlOΎ 8.94 7.90 7.19 1.06 4.07 3.80 2.59 5.21 8.27 CrOΏ 0.01 0.01 0.04 0.02 0.01 0.00 0.00 0.01 0.00 MgO 10.83 11.09 11.66 13.85 10.09 12.25 14.88 12.54 11.10 CaO 22.08 22.05 21.30 22.21 22.32 21.36 22.57 22.46 22.37 MnO 0.26 0.26 0.21 0.35 0.53 0.49 0.35 0.27 0.22 FeO 9.37 9.39 9.30 9.24 12.14 9.47 6.36 8.46 9.10 NaO 0.71 0.65 0.44 0.51 0.77 1.39 0.67 0.54 0.68 KO 0.01 0.00 0.02 0.01 0.04 0.06 0.04 0.01 0.00 NiO 0.02 0.01 0.00 0.01 0.02 0.00 0.00 0.01 0.00 F 0.10 0.09 0.27 0.18 0.32 0.20 0.61 0.26 0.08 Cl 0.00 0.00 0.01 0.01 0.01 0.00 0.00 0.01 0.00 Total 100.50 100.02 99.56 100.95 100.90 101.55 101.31 100.73 100.37
Si 1.681 1.733 1.742 1.963 1.859 1.891 1.915 1.828 1.707 Ti 0.088 0.064 0.085 0.012 0.036 0.029 0.024 0.047 0.079 Alƍᵛ 0.319 0.267 0.257 0.036 0.140 0.109 0.085 0.172 0.293 Al ᵛƍ 0.075 0.082 0.063 0.010 0.040 0.056 0.027 0.056 0.070 Cr 0.000 0.000 0.001 0.000 0.000 0.000 0.000 0.000 0.000 Mg 0.602 0.619 0.656 0.764 0.567 0.670 0.811 0.693 0.617 Ca 0.883 0.885 0.862 0.880 0.901 0.840 0.884 0.893 0.894 Mn 0.008 0.008 0.007 0.011 0.017 0.015 0.011 0.008 0.007 Fe³Ά 0.120 0.103 0.056 0.039 0.085 0.095 0.057 0.060 0.115 Fe²Ά 0.173 0.191 0.238 0.247 0.298 0.196 0.138 0.203 0.168 Na 0.051 0.047 0.032 0.037 0.056 0.099 0.048 0.039 0.049 K 0.000 0.000 0.001 0.001 0.002 0.003 0.002 0.000 0.000
Mg# 77.70 76.45 73.38 75.58 65.56 77.39 85.49 77.39 78.56
End-members Wo 53 52 49 47 51 49 48 50 53 En 36 37 37 40 32 39 44 39 37 Fs 10 11 14 13 17 11 8 11 10 Structural formulae on the basis of 6 O. Spaces left blank denote no data was collected for that oxide/element. 143 Electron Analysis Host: Clinopyroxene MS169B1-13 MS169B1-08 MS169B1-07 MS169B1-06 MS169B1-05 MS169B1-04 MS169A-65 MS169A-64 MS169A-61 MS169A-60 Diopside Diopside Diopside Diopside Diopside Diopside Diopside Diopside Diopside Diopside Unidentified Rim Mantle Mantle Core Core Unidentified Unidentified Unidentified Unidentified SiO 47.91 49.30 46.15 44.75 47.95 47.92 42.00 47.07 52.11 43.12 TiO 1.74 0.73 2.35 2.73 1.68 1.81 4.45 2.06 0.65 3.80 Al OΎ 5.48 2.28 7.24 8.13 5.29 5.60 10.82 6.55 1.43 10.66 CrOΏ 0.00 0.01 0.00 0.00 0.00 0.00 MgO 12.78 10.46 11.71 10.27 12.68 12.49 9.57 10.41 12.02 10.90 CaO 22.46 22.45 22.28 21.65 22.39 22.23 21.34 22.01 21.60 22.18 MnO 0.23 0.69 0.24 0.30 0.22 0.25 0.21 0.36 0.51 0.13 FeO 8.38 12.30 8.96 10.55 8.55 8.96 9.77 10.81 9.90 7.46 Na O 0.61 0.57 0.62 0.62 0.53 0.58 0.69 0.67 0.75 0.52 K O 0.01 0.02 0.00 0.01 0.00 0.01 0.00 0.05 0.01 0.00 NiO 0.00 0.01 0.01 0.00 0.00 0.01 F 0.00 0.15 0.06 0.30 0.18 0.14 0.18 0.00 0.10 0.02 Cl 0.00 0.00 0.00 0.00 0.00 0.01 0.00 0.03 0.00 0.00 Total 99.58 98.96 99.62 99.31 99.47 100.01 99.03 100.00 99.06 98.79
Si 1.788 1.894 1.730 1.702 1.798 1.789 1.602 1.775 1.976 1.628 Ti 0.049 0.021 0.066 0.078 0.047 0.051 0.127 0.058 0.018 0.108 Alƍ ᵛ 0.212 0.103 0.270 0.298 0.202 0.211 0.399 0.225 0.024 0.371 Al ᵛƍ 0.029 0.000 0.051 0.066 0.031 0.035 0.088 0.066 0.039 0.103 Cr 0.000 0.000 0.000 0.000 0.000 0.000 Mg 0.711 0.599 0.655 0.582 0.709 0.695 0.544 0.585 0.679 0.614 Ca 0.898 0.924 0.895 0.882 0.899 0.889 0.872 0.889 0.877 0.898 Mn 0.007 0.022 0.008 0.010 0.007 0.008 0.007 0.011 0.016 0.004 Fe³Ά 0.129 0.103 0.131 0.121 0.115 0.116 0.107 0.091 0.003 0.091 Fe²Ά 0.132 0.292 0.149 0.214 0.153 0.164 0.204 0.249 0.311 0.145 Na 0.044 0.042 0.045 0.045 0.038 0.042 0.051 0.049 0.055 0.038 K 0.000 0.001 0.000 0.001 0.000 0.001 0.000 0.002 0.000 0.000
Mg# 84.31 67.26 81.44 73.09 82.25 80.93 72.68 70.12 68.60 80.89
End-members Wo 52 51 53 53 51 51 54 52 47 54 En 41 33 39 35 40 40 34 34 36 37 Fs 8 16 9 13 9 9 13 14 17 9 Structural formulae on the basis of 6 O. Spaces left blank denote no data was collected for that oxide/element. 144 Electron Analysis Host: Clinopyroxene MS169A-57 MS169A-56 MS169A-55 MS169A-54 MS169A-53 MS169A-52 MS169A-49 MS169A-47 MS169A-34 MS169A-32 Diopside Diopside Diopside Diopside Diopside Diopside Diopside Diopside Diopside Diopside Rim Rim Rim Mantle Core Core Unidentified Unidentified Unidentified Unidentified SiO 48.30 45.03 48.24 46.03 49.83 47.22 43.78 51.51 46.81 50.76 TiO 1.72 2.58 1.91 2.71 0.96 2.30 3.41 1.33 2.32 0.73 Al OΎ 5.18 8.16 5.54 7.30 3.15 6.09 9.89 2.90 6.51 1.52 CrOΏ 0.01 0.00 0.00 0.00 0.00 0.02 MgO 12.23 8.84 11.79 10.80 10.37 11.20 10.64 13.84 11.87 8.74 CaO 21.97 21.72 22.16 22.07 21.67 22.15 21.40 20.62 21.20 20.08 MnO 0.27 0.33 0.22 0.21 0.42 0.23 0.19 0.26 0.23 0.65 FeO 8.93 11.45 8.93 8.89 12.26 9.52 8.66 7.74 9.02 14.32 Na O 0.56 0.78 0.57 0.65 0.57 0.66 0.71 0.83 0.53 1.55 K O 0.00 0.02 0.02 0.05 NiO 0.00 0.00 0.00 0.00 0.00 0.01 F 0.07 0.00 0.06 0.19 Cl 0.00 0.00 0.02 0.00 Total 99.16 98.88 99.36 98.66 99.22 99.39 98.75 99.04 98.58 98.57
Si 1.818 1.725 1.816 1.749 1.905 1.782 1.659 1.926 1.776 1.968 Ti 0.049 0.074 0.054 0.077 0.028 0.065 0.097 0.037 0.066 0.021 Alƍ ᵛ 0.182 0.275 0.184 0.251 0.095 0.218 0.341 0.074 0.224 0.032 Al ᵛƍ 0.048 0.094 0.061 0.076 0.046 0.053 0.101 0.054 0.068 0.037 Cr 0.000 0.000 0.000 0.000 0.000 0.001 Mg 0.687 0.505 0.662 0.612 0.591 0.630 0.601 0.772 0.672 0.505 Ca 0.886 0.892 0.894 0.898 0.887 0.895 0.869 0.826 0.862 0.834 Mn 0.008 0.011 0.007 0.007 0.013 0.007 0.006 0.008 0.007 0.021 Fe³Ά 0.077 0.090 0.057 0.069 0.036 0.083 0.176 0.237 0.224 0.396 Fe²Ά 0.204 0.276 0.224 0.214 0.356 0.218 0.098 0.005 0.063 0.069 Na 0.041 0.058 0.041 0.048 0.043 0.048 0.052 0.060 0.039 0.117 K 0.000 0.001 0.001 0.002
Mg# 77.07 64.63 74.67 74.10 62.42 74.31 85.94 99.42 91.48 88.04
End-members Wo 50 53 50 52 48 51 55 52 54 59 En 39 30 37 35 32 36 38 48 42 36 Fs 11 17 13 12 19 12 6 0 4 5 Structural formulae on the basis of 6 O. Spaces left blank denote no data was collected for that oxide/element. 145 Electron Analysis Host: Clinopyroxene MS169A-31 MS169A-30 MS169A-18 MS169A-10 MS114A-70 MS114A-69 MS114A-53 MS114A-52 MS114A-48 MS114A-26 Diopside Diopside Diopside Diopside Diopside Hedenburgite Diopside Diopside Diopside Diopside Unidentified Unidentified Unidentified Unidentified Unidentified Unidentified Unidentified Unidentified Unidentified Unidentified SiO 50.93 48.64 50.49 46.70 47.10 44.86 49.80 45.61 47.85 48.25 TiO 0.68 1.59 0.74 2.08 1.80 2.86 0.99 1.96 1.73 1.50 Al OΎ 1.50 5.27 2.66 7.20 6.39 7.24 3.37 7.11 5.50 4.94 CrOΏ MgO 8.70 12.33 10.99 11.24 9.48 6.42 10.17 8.81 10.34 10.43 CaO 19.98 21.87 21.91 22.02 21.87 21.10 22.07 21.59 22.04 22.08 MnO 0.62 0.24 0.49 0.21 0.37 0.58 0.44 0.46 0.37 0.38 FeO 14.40 8.88 10.94 8.80 11.89 15.36 11.63 12.89 10.54 10.45 Na O 1.55 0.52 0.54 0.72 0.83 0.96 0.66 0.75 0.77 0.71 K O 0.02 0.00 0.03 0.00 0.01 0.08 0.00 0.00 0.00 0.01 NiO F 0.04 0.11 0.00 0.06 0.15 0.00 0.03 0.02 0.00 0.12 Cl 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.01 Total 98.40 99.44 98.79 99.03 99.89 99.46 99.15 99.21 99.13 98.88
Si 1.975 1.827 1.930 1.762 1.787 1.743 1.903 1.748 1.818 1.841 Ti 0.020 0.045 0.021 0.059 0.051 0.084 0.028 0.057 0.050 0.043 Alƍ ᵛ 0.025 0.173 0.070 0.238 0.213 0.257 0.097 0.252 0.182 0.159 Al ᵛƍ 0.043 0.060 0.050 0.082 0.073 0.075 0.054 0.070 0.064 0.063 Cr Mg 0.503 0.690 0.626 0.632 0.536 0.372 0.579 0.503 0.586 0.593 Ca 0.830 0.880 0.897 0.890 0.889 0.878 0.903 0.887 0.897 0.903 Mn 0.020 0.007 0.016 0.007 0.012 0.019 0.014 0.015 0.012 0.012 Fe³Ά 0.408 0.218 0.018 0.091 0.098 0.087 0.035 0.125 0.259 0.063 Fe²Ά 0.059 0.061 0.332 0.187 0.279 0.413 0.336 0.288 0.075 0.271 Na 0.116 0.038 0.040 0.053 0.061 0.072 0.049 0.056 0.057 0.052 K 0.001 0.000 0.001 0.000 0.001 0.004 0.000 0.000 0.000 0.000
Mg# 89.55 91.91 65.37 77.19 65.75 47.42 63.25 63.59 88.59 68.65
End-members Wo 60 54 48 52 52 53 50 53 58 51 En 36 42 34 37 31 22 32 30 38 34 Fs 4 4 18 11 16 25 18 17 5 15 Structural formulae on the basis of 6 O. Spaces left blank denote no data was collected for that oxide/element. 146 Electron Analysis Host: Clinopyroxene MS114A-04 MS114A-03 MS114A-01 MS113A-71 MS113A-70 MS113A-59 MS113A-50 MS113A-49 MS113A-46 MS113A-45 Diopside Hedenburgite Diopside Diopside Diopside Diopside Diopside Diopside Diopside Diopside Rim Rim Core Unidentified Unidentified Unidentified Unidentified Unidentified Rim Core SiO 48.88 49.32 44.90 45.79 42.00 44.46 45.14 45.39 50.15 45.97 TiO 1.26 0.85 3.20 2.40 4.12 2.61 2.76 2.71 0.78 2.70 Al OΎ 4.38 2.65 9.11 6.78 10.99 8.46 8.25 8.21 2.25 7.41 CrOΏ MgO 10.52 7.39 11.40 10.77 10.66 10.61 10.53 10.93 10.07 11.89 CaO 21.96 20.77 21.75 21.28 20.71 21.77 21.74 21.94 21.63 21.56 MnO 0.36 0.83 0.13 0.33 0.18 0.25 0.26 0.25 0.65 0.21 FeO 10.54 15.33 7.10 10.57 9.21 9.25 9.32 8.95 12.32 8.65 Na O 0.73 1.38 0.69 0.61 0.63 0.63 0.67 0.64 0.91 0.50 K O 0.00 0.01 0.00 0.02 0.00 0.02 0.01 0.01 0.04 0.00 NiO F 0.03 0.03 0.06 0.00 0.14 0.10 0.00 0.05 0.02 0.19 Cl 0.00 0.01 0.00 0.01 0.00 0.01 0.00 0.01 0.01 0.00 Total 98.65 98.57 98.33 98.55 98.64 98.17 98.68 99.07 98.83 99.08
Si 1.867 1.924 1.699 1.749 1.597 1.698 1.716 1.715 1.925 1.734 Ti 0.036 0.025 0.091 0.069 0.118 0.075 0.079 0.077 0.023 0.077 Alƍ ᵛ 0.133 0.076 0.301 0.251 0.403 0.302 0.284 0.285 0.075 0.270 Al ᵛƍ 0.064 0.046 0.105 0.054 0.089 0.080 0.085 0.081 0.027 0.059 Cr Mg 0.599 0.429 0.643 0.613 0.604 0.604 0.597 0.616 0.576 0.669 Ca 0.899 0.868 0.882 0.871 0.844 0.891 0.885 0.888 0.890 0.871 Mn 0.012 0.027 0.004 0.011 0.006 0.008 0.008 0.008 0.021 0.007 Fe³Ά 0.051 0.085 0.065 0.233 0.168 0.177 0.206 0.186 0.070 0.095 Fe²Ά 0.286 0.415 0.160 0.105 0.125 0.119 0.091 0.096 0.325 0.178 Na 0.054 0.104 0.050 0.045 0.046 0.047 0.049 0.047 0.068 0.036 K 0.000 0.000 0.000 0.001 0.000 0.001 0.000 0.000 0.002 0.000
Mg# 67.69 50.87 80.10 85.43 82.89 83.58 86.81 86.47 63.93 79.02
End-members Wo 50 51 52 55 54 55 56 55 50 51 En 34 25 38 39 38 37 38 38 32 39 Fs 16 24 9 7 8 7 6 6 18 10 Structural formulae on the basis of 6 O. Spaces left blank denote no data was collected for that oxide/element. 147 Electron Analysis Host: Clinopyroxene MS113A-24 MS113A-19 MS113A-18 MS113A-17 MS113A-15 MS113A-14 MS113A-13 MS113A-12 MS113A-11 MS113A-10 Diopside Diopside Diopside Diopside Diopside Diopside Diopside Diopside Diopside Diopside Unidentified Rim Mantle Mantle Core Core Rim Rim Mantle Core SiO 41.46 42.58 40.48 43.48 47.93 49.03 47.65 47.62 48.07 45.37 TiO 4.83 3.68 4.91 3.47 1.69 1.01 1.91 1.74 1.67 2.70 Al OΎ 11.12 10.86 12.47 9.96 5.30 3.75 5.52 5.45 5.45 7.66 CrOΏ MgO 9.75 10.56 9.90 10.71 10.80 10.16 12.03 11.02 12.02 11.49 CaO 21.43 21.48 21.64 21.84 21.66 21.34 22.19 21.78 21.73 21.10 MnO 0.15 0.13 0.13 0.17 0.36 0.41 0.20 0.34 0.25 0.18 FeO 8.88 8.30 8.60 8.28 10.63 12.60 8.35 10.14 8.90 9.17 Na O 0.66 0.61 0.59 0.64 0.61 0.66 0.54 0.53 0.51 0.51 K O 0.01 0.01 0.00 0.01 0.00 0.00 0.02 0.01 0.03 0.01 NiO F 0.01 0.00 0.00 0.02 0.13 0.02 0.07 0.00 0.00 0.07 Cl 0.00 0.01 0.01 0.00 0.01 0.01 0.00 0.01 0.00 0.02 Total 98.29 98.21 98.73 98.58 99.11 98.98 98.49 98.62 98.61 98.27
Si 1.587 1.620 1.538 1.649 1.824 1.879 1.806 1.816 1.821 1.729 Ti 0.139 0.105 0.140 0.099 0.048 0.029 0.055 0.050 0.047 0.077 Alƍ ᵛ 0.413 0.380 0.462 0.352 0.176 0.121 0.193 0.184 0.179 0.271 Al ᵛƍ 0.088 0.107 0.097 0.094 0.061 0.048 0.053 0.061 0.064 0.073 Cr Mg 0.556 0.599 0.561 0.605 0.613 0.580 0.680 0.626 0.679 0.653 Ca 0.879 0.876 0.881 0.887 0.883 0.876 0.901 0.890 0.882 0.861 Mn 0.005 0.004 0.004 0.005 0.012 0.013 0.007 0.011 0.008 0.006 Fe³Ά 0.096 0.107 0.128 0.107 0.063 0.064 0.071 0.063 0.057 0.081 Fe²Ά 0.188 0.157 0.146 0.155 0.275 0.340 0.194 0.260 0.225 0.211 Na 0.049 0.045 0.044 0.047 0.045 0.049 0.039 0.039 0.038 0.038 K 0.001 0.000 0.000 0.001 0.000 0.000 0.001 0.000 0.001 0.000
Mg# 74.75 79.28 79.40 79.58 69.03 63.05 77.80 70.66 75.11 75.58
End-members Wo 54 54 55 54 50 49 51 50 49 50 En 34 37 35 37 35 32 38 35 38 38 Fs 12 10 9 9 16 19 11 15 13 12 Structural formulae on the basis of 6 O. Spaces left blank denote no data was collected for that oxide/element. 148 Electron Analysis Host: Clinopyroxene MS113A-09 MS113A-08 Diopside Diopside Core Core SiO 47.13 40.56 TiO 2.15 4.62 Al OΎ 6.56 12.57 CrOΏ MgO 13.20 10.05 CaO 21.70 21.63 MnO 0.14 0.13 FeO 7.16 8.07 Na O 0.49 0.58 K O 0.02 0.02 NiO F 0.20 0.06 Cl 0.00 0.00 Total 98.73 98.27
Si 1.771 1.545 Ti 0.061 0.132 Alƍ ᵛ 0.229 0.455 Al ᵛƍ 0.061 0.110 Cr Mg 0.739 0.571 Ca 0.873 0.883 Mn 0.005 0.004 Fe³Ά 0.082 0.123 Fe²Ά 0.143 0.134 Na 0.036 0.043 K 0.001 0.001
Mg# 83.79 80.97
End-members Wo 50 56 En 42 36 Fs 8 8 Structural formulae on the basis of 6 O. Spaces left blank denote no data was collected for that oxide/element. 149 Electron Analysis Host: Clinopyroxene MB07-167_C4R MB07-167_C4Cb MB07-167_C4C MB07-167_C3Cb MB07-167_C3C MB07-145_CC1B MB07-145_CC1 Diopside Diopside Diopside Diopside Diopside Diopside Diopside Rim Core Core Core Core Core Core SiO 45.01 49.81 48.57 46.04 46.05 43.05 43.62 TiO 3.14 1.30 1.70 2.46 2.69 3.36 1.93 Al OΎ 9.09 5.44 6.49 8.31 8.71 8.77 5.41 MgO 12.26 15.39 14.76 13.53 13.28 10.99 9.62 CaO 22.20 22.59 22.44 22.49 22.47 21.87 19.92 MnO 0.14 0.07 0.08 0.08 0.11 0.20 0.30 FeO 6.83 4.28 4.54 5.51 5.55 8.66 9.52 Na O 0.53 0.46 0.51 0.51 0.51 0.73 0.68 K O -0.01 0.01 0.00 0.01 0.01 0.01 0.02 F 0.03 -0.07 Cl 0.01 0.01 0.00 0.00 0.00 0.01 0.17 Total 99.19 99.34 99.11 98.94 99.38 97.68 91.11
Si 6.50 7.05 7.21 6.62 6.59 6.40 6.95 Ti 0.34 0.14 0.19 0.27 0.29 0.38 0.23 Alƍ ᵛ 0.88 0.27 0.43 0.75 0.78 0.98 0.34 ᵛA l ƍ 0.81 0.72 0.77 0.79 0.83 0.71 0.78 Mg 2.64 3.25 3.27 2.90 2.84 2.44 2.28 Ca 3.44 3.43 3.57 3.46 3.45 3.48 3.40 Mn 0.02 0.01 0.01 0.01 0.01 0.03 0.04 Fe³Ά 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Fe²Ά 0.90 0.55 0.59 0.73 0.73 1.18 1.40 Na 0.15 0.13 0.15 0.14 0.14 0.21 0.21 K 0.00 0.00 0.00 0.00 0.00 0.00 0.00
Mg# 74.53 85.42 84.67 79.98 79.58 67.36 62.02
End-members Wo 49 47 48 49 49 49 48 En 38 45 44 41 40 34 32 Fs 13 8 8 10 10 17 20 Structural formulae on the basis of 6 O. Spaces left blank denote no data was collected for that oxide/element. 150 Electron Analysis Host: Clinopyroxene MB07-141_CR4B MB07-141_CR4 MB07-141_CC4C MB07-141_CC4B MB07-141_CC4 MB07-028_C2R MB07-028_C2C Diopside Diopside Diopside Diopside Diopside Diopside Diopside Rim Rim Core Core Core Rim Core SiO 48.44 45.82 43.71 42.26 42.92 48.03 47.31 TiO 2.16 2.68 3.26 3.92 3.37 0.88 0.84 Al OΎ 6.27 8.33 10.33 11.34 11.10 2.18 2.68 MgO 14.09 12.78 11.88 11.26 11.34 12.11 10.63 CaO 22.63 22.33 21.98 22.05 21.88 21.12 20.82 MnO 0.12 0.10 0.11 0.10 0.11 1.04 1.08 FeO 5.97 6.35 7.02 7.31 7.50 11.22 12.96 Na O 0.38 0.45 0.57 0.53 0.57 0.46 0.52 K O 0.02 -0.01 0.01 0.00 0.02 0.03 0.02 F 0.06 0.04 0.13 0.21 -0.03 Cl 0.00 0.01 0.02 0.00 0.00 0.02 0.03 Total 100.13 98.88 99.02 98.97 98.78 97.11 96.89
Si 6.88 6.62 6.34 6.16 6.26 7.24 7.20 Ti 0.23 0.29 0.36 0.43 0.37 0.10 0.10 Alƍ ᵛ 0.46 0.75 1.07 1.26 1.18 0.15 0.18 ᵛA l ƍ 0.69 0.81 0.86 0.87 0.90 0.27 0.34 Mg 2.98 2.75 2.57 2.44 2.47 2.72 2.41 Ca 3.44 3.45 3.42 3.44 3.42 3.41 3.40 Mn 0.01 0.01 0.01 0.01 0.01 0.13 0.14 Fe³Ά 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Fe²Ά 0.78 0.84 0.93 0.97 1.00 1.53 1.79 Na 0.11 0.13 0.16 0.15 0.16 0.14 0.15 K 0.00 0.00 0.00 0.00 0.00 0.01 0.00
Mg# 79.34 76.61 73.40 71.48 71.21 63.96 57.40
End-members Wo 48 49 49 50 50 44 45 En 41 39 37 36 36 36 32 Fs 11 12 13 14 14 20 24 Structural formulae on the basis of 6 O. Spaces left blank denote no data was collected for that oxide/element. 151 Electron Analysis Host: Clinopyroxene MB07-028_C1Cb MB07-028_C1C MB07-017_CR3 MB07-017_CR2 MB07-017_COR2 MB07-017_CC55T9 MB07-017_CC55T8 Diopside Diopside Diopside Diopside Diopside Diopside Diopside Core Core Rim Rim Rim Core Core SiO 44.61 43.90 43.59 47.03 46.23 44.43 44.98 TiO 2.24 2.29 3.82 2.48 2.91 2.18 2.20 Al OΎ 6.36 6.66 9.43 6.19 7.26 5.78 5.76 MgO 11.50 11.44 11.49 13.28 12.05 11.18 12.03 CaO 20.96 21.33 22.07 21.85 21.51 21.45 21.31 MnO 0.88 0.88 0.16 0.14 0.22 0.70 0.66 FeO 9.95 9.91 7.99 7.48 8.57 9.94 9.00 Na O 0.60 0.65 0.64 0.49 0.67 0.69 0.57 K O 0.05 0.03 0.02 0.01 0.02 0.03 0.03 F 0.08 -0.02 0.03 Cl 0.02 0.02 0.02 0.01 0.02 0.04 0.04 Total 97.17 97.10 99.31 98.96 99.49 96.42 96.58
Si 6.70 6.62 6.35 6.81 6.70 6.74 6.77 Ti 0.25 0.26 0.42 0.27 0.32 0.25 0.25 Alƍ ᵛ 0.75 0.83 1.05 0.58 0.70 0.64 0.64 ᵛA l ƍ 0.47 0.46 0.72 0.57 0.65 0.49 0.47 Mg 2.57 2.57 2.49 2.87 2.60 2.53 2.70 Ca 3.37 3.44 3.44 3.39 3.34 3.49 3.43 Mn 0.11 0.11 0.02 0.02 0.03 0.09 0.08 Fe³Ά 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Fe²Ά 1.35 1.35 1.06 0.99 1.13 1.38 1.23 Na 0.18 0.19 0.18 0.14 0.19 0.20 0.17 K 0.01 0.00 0.00 0.00 0.00 0.01 0.01
Mg# 65.57 65.48 70.09 74.40 69.68 64.75 68.66
End-members Wo 46 47 49 47 47 47 47 En 35 35 36 40 37 34 37 Fs 19 18 15 14 16 19 17 Structural formulae on the basis of 6 O. Spaces left blank denote no data was collected for that oxide/element. 152 Electron Analysis Host: Clinopyroxene MB07-017_CC55T7 MB07-017_CC55T6 MB07-017_CC55T5 MB07-017_CC55T4 MB07-017_CC55T3 MB07-017_CC55T2 Diopside Diopside Diopside Diopside Diopside Diopside Core Core Core Core Core Core SiO 44.60 44.95 40.65 41.21 42.29 42.95 TiO 2.26 2.10 3.77 3.79 3.20 3.03 Al OΎ 6.17 5.96 9.18 9.48 7.66 7.25 MgO 11.93 11.16 10.87 11.09 11.02 11.12 CaO 21.69 21.56 21.57 21.37 21.47 21.52 MnO 0.66 0.66 0.59 0.58 0.63 0.62 FeO 8.94 10.02 8.77 8.97 9.18 9.41 Na O 0.66 0.70 0.57 0.57 0.68 0.62 K O 0.03 0.01 0.03 0.01 0.02 0.01 F Cl 0.01 0.02 0.04 0.02 0.02 0.01 Total 96.94 97.14 96.05 97.09 96.16 96.53
Si 6.99 6.76 6.19 6.20 6.43 6.50 Ti 0.27 0.24 0.43 0.43 0.37 0.34 Alƍ ᵛ 0.70 0.62 1.25 1.28 0.99 0.91 ᵛA l ƍ 0.49 0.54 0.54 0.54 0.51 0.50 Mg 2.79 2.50 2.47 2.49 2.50 2.51 Ca 3.64 3.47 3.52 3.44 3.50 3.49 Mn 0.09 0.08 0.08 0.07 0.08 0.08 Fe³Ά 0.00 0.00 0.00 0.00 0.00 0.00 Fe²Ά 1.22 1.38 1.22 1.22 1.27 1.30 Na 0.20 0.21 0.17 0.17 0.20 0.18 K 0.01 0.00 0.01 0.00 0.00 0.00
Mg# 69.47 64.50 66.99 67.05 66.26 65.89
End-members Wo 48 47 49 48 48 48 En 36 34 34 35 34 34 Fs 16 19 17 17 18 18 Structural formulae on the basis of 6 O. Spaces left blank denote no data was collected for that oxide/element. 153 Electron Analysis Host: Clinopyroxene MB07-017_CC55T14 MB07-017_CC55T13 MB07-017_CC55T12 MB07-017_CC55T11 MB07-017_CC55T10 MB07-017_CC55T1 Diopside Diopside Diopside Diopside Diopside Diopside Rim Core Core Core Core Rim SiO 41.52 39.30 44.39 44.24 44.60 43.13 TiO 3.56 4.34 2.15 2.16 2.23 3.26 Al OΎ 8.28 10.20 5.84 5.78 5.83 6.88 MgO 10.67 10.38 11.27 11.25 11.36 11.23 CaO 21.53 21.28 21.41 21.75 21.51 21.34 MnO 0.63 0.57 0.72 0.69 0.74 0.71 FeO 9.82 9.16 9.91 9.82 9.88 9.43 Na O 0.64 0.61 0.71 0.70 0.67 0.58 K O 0.04 0.02 0.04 0.01 0.01 0.03 F Cl 0.00 0.04 0.02 0.02 0.04 0.03 Total 96.69 95.89 96.47 96.42 96.86 96.61
Si 6.31 6.02 6.73 6.72 6.73 6.81 Ti 0.41 0.50 0.25 0.25 0.25 0.39 Alƍ ᵛ 1.13 1.47 0.66 0.65 0.66 0.90 ᵛA l ƍ 0.48 0.53 0.48 0.48 0.47 0.44 Mg 2.42 2.37 2.55 2.55 2.56 2.64 Ca 3.50 3.49 3.48 3.54 3.48 3.61 Mn 0.08 0.07 0.09 0.09 0.09 0.10 Fe³Ά 0.00 0.00 0.00 0.00 0.00 0.00 Fe²Ά 1.36 1.27 1.37 1.36 1.36 1.30 Na 0.19 0.18 0.21 0.21 0.20 0.18 K 0.01 0.00 0.01 0.00 0.00 0.01
Mg# 64.02 65.04 65.02 65.11 65.28 67.05
End-members Wo 48 49 47 47 47 48 En 33 33 34 34 35 35 Fs 19 18 19 18 18 17 Structural formulae on the basis of 6 O. Spaces left blank denote no data was collected for that oxide/element. 154 Electron Analysis Host: Clinopyroxene MB07-017_CC52C MB07-017_CC52B MB07-017_CC52 MB07-017_CC51B MB07-017_CC51 MB07-017_CC3 MB07-017_CC2 Diopside Diopside Diopside Diopside Diopside Diopside Diopside Core Core Core Core Core Core Core SiO 44.75 44.81 44.21 45.39 45.29 46.69 47.24 TiO 2.49 2.26 2.66 2.28 2.17 2.25 2.29 Al OΎ 6.10 5.96 6.23 6.05 5.70 6.56 6.21 MgO 11.23 11.42 11.72 11.43 11.51 12.00 12.90 CaO 21.36 21.38 21.55 21.91 21.69 22.05 22.08 MnO 0.59 0.62 0.59 0.50 0.54 0.21 0.22 FeO 9.51 9.48 8.76 9.55 9.76 8.70 7.87 Na O 0.67 0.71 0.59 0.71 0.71 0.69 0.62 K O 0.02 0.03 0.03 0.00 0.01 0.02 0.00 F 0.09 0.00 Cl 0.04 0.02 0.03 0.01 0.02 -0.01 0.01 Total 96.75 96.69 96.36 97.84 97.41 99.26 99.46
Si 6.74 6.75 6.67 6.76 6.78 6.79 6.83 Ti 0.28 0.26 0.30 0.26 0.24 0.25 0.25 Alƍ ᵛ 0.64 0.63 0.71 0.59 0.59 0.55 0.54 ᵛA l ƍ 0.55 0.53 0.50 0.57 0.51 0.69 0.62 Mg 2.52 2.56 2.64 2.54 2.57 2.60 2.78 Ca 3.45 3.45 3.48 3.49 3.48 3.43 3.42 Mn 0.07 0.08 0.08 0.06 0.07 0.03 0.03 Fe³Ά 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Fe²Ά 1.31 1.30 1.21 1.30 1.34 1.16 1.04 Na 0.20 0.21 0.17 0.21 0.21 0.20 0.17 K 0.00 0.01 0.01 0.00 0.00 0.00 0.00
Mg# 65.82 66.30 68.58 66.07 65.80 69.14 72.78
End-members Wo 47 47 48 48 47 48 47 En 35 35 36 35 35 36 38 Fs 18 18 16 18 18 16 14 Structural formulae on the basis of 6 O. Spaces left blank denote no data was collected for that oxide/element. 155 Electron Analysis Host: Clinopyroxene MB06-827_C5R MB06-827_C5C Diopside Diopside Rim Core SiO 50.36 47.86 TiO 1.32 2.17 Al OΎ 3.36 5.79 MgO 13.51 13.00 CaO 21.98 22.10 MnO 0.38 0.21 FeO 8.79 7.92 Na O 0.57 0.62 K O 0.02 0.02 F Cl 0.00 0.00 Total 100.27 99.69
Si 7.21 6.89 Ti 0.14 0.23 Alƍ ᵛ 0.12 0.46 ᵛA l ƍ 0.50 0.62 Mg 2.89 2.79 Ca 3.37 3.41 Mn 0.05 0.03 Fe³Ά 0.00 0.00 Fe²Ά 1.15 1.04 Na 0.16 0.17 K 0.00 0.00
Mg# 71.52 72.78
End-members Wo 46 47 En 39 39 Fs 16 14 Structural formulae on the basis of 6 O. Spaces left blank denote no data was collected for that oxide/element. 156 APPENDIX B. GEOTHERMOBAROMETRY Geothermobarometry Host: Amphibole
SAMPLE MS169N2-76 MS169N2-75 MS169N2-74 MS169N2-73 MS169N2-72 MS169N2-65 MS169N2-64 MS169N2-63
Physical-chemical conditions
T (°C) 1058.27 1047.58 1058.13 1055.58 1079.72 1057.67 1019.39 1063.53 uncertainty (°C) 22.00 22.00 22.00 22.00 22.00 22.00 22.00 22.00 P (MPa) 690.18 634.46 701.05 690.92 739.67 703.95 708.56 740.30 P (kbar) 6.90 6.34 7.01 6.91 7.40 7.04 7.09 7.40 uncertainty (kbar) 0.76 0.70 0.77 0.76 0.81 0.77 0.78 0.81 157
Geothermobarometry Host: Amphibole
SAMPLE MS169N2-62 MS169N2-61 MS169N2-56 MS169N2-55 MS169N2-49 MS169N2-48 MS169N2-47 MS169N2-46
Physical-chemical conditions
T (°C) 1063.89 1058.63 1051.31 1078.71 1058.24 1056.71 1065.34 1099.88 uncertainty (°C) 22.00 22.00 22.00 22.00 22.00 22.00 22.00 22.00 P (MPa) 728.35 755.26 662.65 781.07 682.19 698.00 756.04 882.37 P (kbar) 7.28 7.55 6.63 7.81 6.82 6.98 7.56 8.82 uncertainty (kbar) 0.80 0.83 0.73 0.86 0.75 0.77 0.83 0.97 158
Geothermobarometry Host: Amphibole
SAMPLE MS169N2-44 MS169N2-43 MS169N2-26 MS169N2-18 MS169N2-11 MS169N2-10 MS169N2-09 MS169N2-07
Physical-chemical conditions
T (°C) 1063.73 1051.57 1041.30 1083.64 1044.09 1039.21 1045.92 1089.81 uncertainty (°C) 22.00 22.00 22.00 22.00 22.00 22.00 22.00 22.00 P (MPa) 705.86 617.39 619.54 789.82 588.57 584.97 615.17 809.81 P (kbar) 7.06 6.17 6.20 7.90 5.89 5.85 6.15 8.10 uncertainty (kbar) 0.78 0.68 0.68 0.87 0.65 0.64 0.68 0.89 159
Geothermobarometry Host: Amphibole
SAMPLE MS169D-76 MS169D-72 MS169D-58 MS169D-53 MS169D-44 MS169D-40 MS169D-39 MS169D-06 MS169D-05
Physical-chemical conditions
T (°C) 1091.50 1091.15 1059.79 1083.35 1065.27 1077.32 1050.51 1083.20 1087.33 uncertainty (°C) 22.00 22.00 22.00 22.00 22.00 22.00 22.00 22.00 22.00 P (MPa) 792.70 787.40 685.72 825.93 738.14 665.11 657.70 726.88 685.85 P (kbar) 7.93 7.87 6.86 8.26 7.38 6.65 6.58 7.27 6.86 uncertainty (kbar) 0.87 0.87 0.75 0.91 0.81 0.73 0.72 0.80 0.75 160
Geothermobarometry Host: Amphibole
SAMPLE MS169D-04 MS169C-36 MS169C-09 MS169C-08 MS169C-04 MS169C-03 MS169C-02 MS169B1-67 MS169B1-66
Physical-chemical conditions
T (°C) 1098.30 1069.92 1059.52 1092.61 1053.42 1046.93 1050.39 1041.74 1061.12 uncertainty (°C) 22.00 22.00 22.00 22.00 22.00 22.00 22.00 22.00 22.00 P (MPa) 848.90 701.17 799.14 909.98 623.87 703.87 709.56 636.89 724.04 P (kbar) 8.49 7.01 7.99 9.10 6.24 7.04 7.10 6.37 7.24 uncertainty (kbar) 0.93 0.77 0.88 1.00 0.69 0.77 0.78 0.70 0.80 161
Geothermobarometry Host: Amphibole
SAMPLE MS169B1-52 MS169B1-51 MS169B1-50 MS169B1-49 MS169B1-36 MS169B1-20 MS169B1-19 MS169B1-09
Physical-chemical conditions
T (°C) 1054.19 1109.79 1056.63 1041.18 1058.91 1074.14 1073.02 1073.18 uncertainty (°C) 22.00 22.00 22.00 22.00 22.00 22.00 22.00 22.00 P (MPa) 667.40 940.94 685.98 689.41 660.51 804.00 651.55 733.65 P (kbar) 6.67 9.41 6.86 6.89 6.61 8.04 6.52 7.34 uncertainty (kbar) 0.73 1.04 0.75 0.76 0.73 0.88 0.72 0.81 162
Geothermobarometry Host: Amphibole
SAMPLE MS169A-68 MS169A-67 MS169A-66 MS169A-46 MS169A-45 MS169A-44 MS169A-41 MS169A-40 MS169A-39
Physical-chemical conditions
T (°C) 1063.49 1070.43 1066.85 1046.08 1059.75 1046.71 1053.10 1087.95 1034.43 uncertainty (°C) 22.00 22.00 22.00 22.00 22.00 22.00 22.00 22.00 22.00 P (MPa) 718.06 755.04 770.01 643.73 693.38 671.66 714.06 824.41 625.65 P (kbar) 7.18 7.55 7.70 6.44 6.93 6.72 7.14 8.24 6.26 uncertainty (kbar) 0.79 0.83 0.85 0.71 0.76 0.74 0.79 0.91 0.69 163
Geothermobarometry Host: Amphibole
SAMPLE MS169A-38 MS169A-37 MS169A-24 MS169A-23 MS169A-22 MS169A-17 MS169A-06 MS169A-04 MS114A-67
Physical-chemical conditions
T (°C) 1084.03 1057.85 1049.57 1096.53 1061.48 1057.89 1061.87 1057.15 1017.60 uncertainty (°C) 22.00 22.00 22.00 22.00 22.00 22.00 22.00 22.00 22.00 P (MPa) 825.46 659.31 734.09 909.11 787.44 716.14 723.27 753.55 578.85 P (kbar) 8.25 6.59 7.34 9.09 7.87 7.16 7.23 7.54 5.79 uncertainty (kbar) 0.91 0.73 0.81 1.00 0.87 0.79 0.80 0.83 0.64 164
Geothermobarometry Host: Amphibole
SAMPLE MS114A-66 MS114A-63 MS114A-62 MS114A-51 MS114A-50 MS114A-44 MS114A-43 MS114A-41 MS114A-40
Physical-chemical conditions
T (°C) 1041.96 1007.41 1022.40 1037.10 1024.88 1063.70 1084.28 1074.42 1078.96 uncertainty (°C) 22.00 22.00 22.00 22.00 22.00 22.00 22.00 22.00 22.00 P (MPa) 666.41 572.32 607.92 692.58 624.94 781.04 836.87 762.14 796.68 P (kbar) 6.66 5.72 6.08 6.93 6.25 7.81 8.37 7.62 7.97 uncertainty (kbar) 0.73 0.63 0.67 0.76 0.69 0.86 0.92 0.84 0.88 165
Geothermobarometry Host: Amphibole
SAMPLE MS114A-28 MS114A-27 MS114A-25 MS114A-23 MS114A-18 MS114A-17 MS114A-16 MS114A-15 MS114A-08
Physical-chemical conditions
T (°C) 1014.53 1048.96 1036.18 1060.37 1082.83 1023.10 1057.11 1030.84 1043.84 uncertainty (°C) 22.00 22.00 22.00 22.00 22.00 22.00 22.00 22.00 22.00 P (MPa) 572.98 625.93 649.87 702.23 876.90 597.56 734.56 630.91 660.74 P (kbar) 5.73 6.26 6.50 7.02 8.77 5.98 7.35 6.31 6.61 uncertainty (kbar) 0.63 0.69 0.71 0.77 0.96 0.66 0.81 0.69 0.73 166
Geothermobarometry Host: Amphibole
SAMPLE MS114A-07 MS113A-69 MS113A-68 MS113A-67 MS113A-66 MS113A-65 MS113A-64 MS113A-63 MS113A-62
Physical-chemical conditions
T (°C) 1027.81 1060.59 1054.85 1100.96 1036.96 1049.34 1067.96 1093.69 1064.97 uncertainty (°C) 22.00 22.00 22.00 22.00 22.00 22.00 22.00 22.00 22.00 P (MPa) 543.90 719.14 732.80 915.71 649.58 652.42 717.12 843.29 721.92 P (kbar) 5.44 7.19 7.33 9.16 6.50 6.52 7.17 8.43 7.22 uncertainty (kbar) 0.60 0.79 0.81 1.01 0.71 0.72 0.79 0.93 0.79 167
Geothermobarometry Host: Amphibole
SAMPLE MS113A-61 MS113A-60 MS113A-58 MS113A-57 MS113A-40 MS113A-39 MS113A-38 MS113A-36 MS113A-35
Physical-chemical conditions
T (°C) 1035.10 1016.63 1087.19 1047.41 1057.31 1035.70 1057.43 1058.76 1066.58 uncertainty (°C) 22.00 22.00 22.00 22.00 22.00 22.00 22.00 22.00 22.00 P (MPa) 628.94 766.20 839.14 706.40 676.49 657.74 705.87 704.65 761.51 P (kbar) 6.29 7.66 8.39 7.06 6.76 6.58 7.06 7.05 7.62 uncertainty (kbar) 0.69 0.84 0.92 0.78 0.74 0.72 0.78 0.78 0.84 168
Geothermobarometry Host: Amphibole
SAMPLE MS113A-34 MB07-185A2_AR42 MB07-185A2_AC43 MB07-185A2_AC42 MB07-185A2_AC41
Physical-chemical conditions
T (°C) 1050.84 1092.92 1062.06 1063.62 1063.73 uncertainty (°C) 22.00 22.00 22.00 22.00 22.00 P (MPa) 672.87 690.11 719.18 707.98 670.04 P (kbar) 6.73 6.90 7.19 7.08 6.70 uncertainty (kbar) 0.74 0.76 0.79 0.78 0.74 169
Geothermobarometry Host: Amphibole
SAMPLE MB07-185A2_AC40B MB07-185A2_AC40 MB07-184_AR51B MB07-184_AR51 MB07-184_AR50B
Physical-chemical conditions
T (°C) 1046.44 1047.57 1050.12 1078.61 1032.47 uncertainty (°C) 22.00 22.00 22.00 22.00 22.00 P (MPa) 621.45 635.06 566.87 681.61 491.91 P (kbar) 6.21 6.35 5.67 6.82 4.92 uncertainty (kbar) 0.68 0.70 0.62 0.75 0.54 170
Geothermobarometry Host: Amphibole
SAMPLE MB07-184_AC50B MB07-184_AC38B MB07-184_AC38 MB07-181_AR13 MB07-181_AR12B MB07-181_AR12
Physical-chemical conditions
T (°C) 1062.72 1078.02 1079.57 1080.77 1070.23 1061.44 uncertainty (°C) 22.00 22.00 22.00 22.00 22.00 22.00 P (MPa) 658.55 792.68 752.48 807.09 713.49 677.39 P (kbar) 6.59 7.93 7.52 8.07 7.13 6.77 uncertainty (kbar) 0.72 0.87 0.83 0.89 0.78 0.75 171
Geothermobarometry Host: Amphibole
SAMPLE MB07-181_AR11 MB07-181_AR10 MB07-181_AOR10 MB07-181_AC12B MB07-181_AC12 MB07-181_AC11
Physical-chemical conditions
T (°C) 1049.91 1036.71 1085.14 1047.62 1048.18 1053.00 uncertainty (°C) 22.00 22.00 22.00 22.00 22.00 22.00 P (MPa) 668.88 640.44 736.45 672.14 710.52 671.79 P (kbar) 6.69 6.40 7.36 6.72 7.11 6.72 uncertainty (kbar) 0.74 0.70 0.81 0.74 0.78 0.74 172
Geothermobarometry Host: Amphibole
SAMPLE MB07-181_AC10 MB07-180C_AR19B MB07-180C_AR19 MB07-180C_AR18 MB07-180C_AOR19 MB07-174_T8
Physical-chemical conditions
T (°C) 1033.66 1054.39 1053.86 1097.02 1016.17 1036.85 uncertainty (°C) 22.00 22.00 22.00 22.00 22.00 22.00 P (MPa) 642.00 714.25 709.31 848.16 549.90 488.74 P (kbar) 6.42 7.14 7.09 8.48 5.50 4.89 uncertainty (kbar) 0.71 0.79 0.78 0.93 0.60 0.54 173
Geothermobarometry Host: Amphibole
SAMPLE MB07-174_T7 MB07-174_T12 MB07-174_T11 MB07-174_AC7 MB07-174_A11Cb MB07-167_A9Cb
Physical-chemical conditions
T (°C) 1036.47 1011.59 1006.98 1019.09 1013.89 1074.14 uncertainty (°C) 22.00 22.00 22.00 22.00 22.00 22.00 P (MPa) 525.44 531.23 476.52 521.60 494.02 634.10 P (kbar) 5.25 5.31 4.77 5.22 4.94 6.34 uncertainty (kbar) 0.58 0.58 0.52 0.57 0.54 0.70 174
Geothermobarometry Host: Amphibole
SAMPLE MB07-167_A9C MB07-167_A8Rb MB07-167_A8R MB07-167_A8Cb MB07-167_A8C MB07-145_AR55
Physical-chemical conditions
T (°C) 1072.18 1088.07 1069.25 1087.49 1065.38 1062.34 uncertainty (°C) 22.00 22.00 22.00 22.00 22.00 22.00 P (MPa) 679.60 635.86 631.22 691.90 660.79 604.50 P (kbar) 6.80 6.36 6.31 6.92 6.61 6.05 uncertainty (kbar) 0.75 0.70 0.69 0.76 0.73 0.66 175
Geothermobarometry Host: Amphibole
SAMPLE MB07-145_AR53B MB07-145_AR53 MB07-145_AR3B MB07-145_AR3 MB07-145_AR2B MB07-145_AR2
Physical-chemical conditions
T (°C) 1108.57 1099.50 1084.82 1093.07 1065.06 1097.63 uncertainty (°C) 22.00 22.00 22.00 22.00 22.00 22.00 P (MPa) 747.01 768.26 772.25 783.07 660.24 816.17 P (kbar) 7.47 7.68 7.72 7.83 6.60 8.16 uncertainty (kbar) 0.82 0.85 0.85 0.86 0.73 0.90 176
Geothermobarometry Host: Amphibole
SAMPLE MB07-145_AC55 MB07-145_AC53C MB07-145_AC53 MB07-145_AC4B MB07-145_AC4 MB07-145_AC2B
Physical-chemical conditions
T (°C) 1019.52 1081.12 1054.71 1036.13 1023.18 1029.07 uncertainty (°C) 22.00 22.00 22.00 22.00 22.00 22.00 P (MPa) 526.27 703.59 606.82 617.29 538.13 572.95 P (kbar) 5.26 7.04 6.07 6.17 5.38 5.73 uncertainty (kbar) 0.58 0.77 0.67 0.68 0.59 0.63 177
Geothermobarometry Host: Amphibole
SAMPLE MB07-145_AC2 MB07-145_AC1 MB07-134_A3Rb MB07-028_A7C MB07-025_A15R MB07-025_A15C
Physical-chemical conditions
T (°C) 1032.72 1079.41 1049.08 1023.16 1053.28 1035.86 uncertainty (°C) 22.00 22.00 22.00 22.00 22.00 22.00 P (MPa) 558.43 730.28 554.04 409.20 629.01 621.47 P (kbar) 5.58 7.30 5.54 4.09 6.29 6.21 uncertainty (kbar) 0.61 0.80 0.61 0.45 0.69 0.68 178
Geothermobarometry Host: Amphibole
SAMPLE MB07-025_A14Cb MB07-025_A14C MB07-017_AR56 MB07-017_AR15 MB07-017_AC57B MB07-017_AC16
Physical-chemical conditions
T (°C) 1028.07 1027.82 1035.86 1090.23 1070.93 1094.38 uncertainty (°C) 22.00 22.00 22.00 22.00 22.00 22.00 P (MPa) 543.11 559.90 496.52 733.44 607.49 751.85 P (kbar) 5.43 5.60 4.97 7.33 6.07 7.52 uncertainty (kbar) 0.60 0.62 0.55 0.81 0.67 0.83 179
Geothermobarometry Host: Amphibole
SAMPLE MB07-017_AC15 MB06-827_A13Cb MB06-827_A13C MB06-827_A12C MB06-508_AR52B MB06-508_AR44
Physical-chemical conditions
T (°C) 1050.72 1016.75 1037.28 1083.65 1036.58 1036.17 uncertainty (°C) 22.00 22.00 22.00 22.00 22.00 22.00 P (MPa) 575.17 438.45 528.04 711.79 449.07 567.71 P (kbar) 5.75 4.38 5.28 7.12 4.49 5.68 uncertainty (kbar) 0.63 0.48 0.58 0.78 0.49 0.62 180
Geothermobarometry Host: Amphibole
SAMPLE MB06-508_AC52B MB06-508_AC52 MB06-508_AC46B MB06-508_AC46 MB06-508_AC45B MB06-508_AC45
Physical-chemical conditions
T (°C) 1032.01 1043.64 1044.62 1041.94 1040.84 1042.44 uncertainty (°C) 22.00 22.00 22.00 22.00 22.00 22.00 P (MPa) 528.12 445.50 496.70 500.92 460.15 488.45 P (kbar) 5.28 4.45 4.97 5.01 4.60 4.88 uncertainty (kbar) 0.58 0.49 0.55 0.55 0.51 0.54 181
Geothermobarometry Host: Amphibole
SAMPLE MB06-508_AC44
Physical-chemical conditions
T (°C) 1042.04 uncertainty (°C) 22.00 P (MPa) 503.23 P (kbar) 5.03 uncertainty (kbar) 0.55 182
Geothermobarometry Host: Clinopyroxene
SAMPLE MS169N2-71 MS169N2-68 MS169N2-58 MS169N2-57 MS169N2-45 MS169N2-29 MS169N2-28 MS169N2-27
Physical-chemical conditions
T (°C) 1009.68 1027.17 1013.12 1012.32 1028.24 1013.39 1023.83 1014.94 uncertainty 33.00 33.00 33.00 33.00 33.00 33.00 33.00 33.00 P (MPa) 724.49 930.53 713.10 800.35 944.94 874.40 904.25 813.36 P (kbar) 7.24 9.31 7.13 8.00 9.45 8.74 9.04 8.13 uncertainty (kbar) 1.70 1.70 1.70 1.70 1.70 1.70 1.70 1.70 183
Geothermobarometry Host: Clinopyroxene
SAMPLE MS169N2-24 MS169N2-20 MS169N2-19 MS169N2-14 MS169N2-13 MS169N2-12 MS169N2-08 MS169D-75
Physical-chemical conditions
T (°C) 1049.96 1015.77 1025.93 1039.58 1038.30 1014.11 1011.33 1025.09 uncertainty 33.00 33.00 33.00 33.00 33.00 33.00 33.00 33.00 P (MPa) 1058.56 747.61 906.34 947.83 971.35 804.02 708.15 915.50 P (kbar) 10.59 7.48 9.06 9.48 9.71 8.04 7.08 9.15 uncertainty (kbar) 1.70 1.70 1.70 1.70 1.70 1.70 1.70 1.70 184
Geothermobarometry Host: Clinopyroxene
SAMPLE MS169D-68 MS169D-67 MS169D-62 MS169D-61 MS169D-60 MS169D-54 MS169D-52 MS169D-46 MS169D-45
Physical-chemical conditions
T (°C) 1036.33 1009.19 1020.96 1003.54 1012.39 1016.88 1010.46 1022.38 1028.79 uncertainty 33.00 33.00 33.00 33.00 33.00 33.00 33.00 33.00 33.00 P (MPa) 916.70 711.69 814.08 749.49 818.43 842.69 726.68 822.40 884.73 P (kbar) 9.17 7.12 8.14 7.49 8.18 8.43 7.27 8.22 8.85 uncertainty (kbar) 1.70 1.70 1.70 1.70 1.70 1.70 1.70 1.70 1.70 185
Geothermobarometry Host: Clinopyroxene
SAMPLE MS169D-43 MS169D-38 MS169D-37 MS169D-32 MS169D-31 MS169D-30 MS169D-29 MS169D-26 MS169D-25
Physical-chemical conditions
T (°C) 1027.79 1013.33 989.01 995.46 1014.81 1027.31 1025.84 1028.82 973.99 uncertainty 33.00 33.00 33.00 33.00 33.00 33.00 33.00 33.00 33.00 P (MPa) 963.81 819.94 547.76 623.02 803.63 934.09 893.51 942.82 330.48 P (kbar) 9.64 8.20 5.48 6.23 8.04 9.34 8.94 9.43 3.30 uncertainty (kbar) 1.70 1.70 1.70 1.70 1.70 1.70 1.70 1.70 1.70 186
Geothermobarometry Host: Clinopyroxene
SAMPLE MS169D-22 MS169D-18 MS169D-17 MS169D-14 MS169D-13 MS169D-12 MS169D-11 MS169D-03 MS169D-02
Physical-chemical conditions
T (°C) 1026.28 1015.10 1007.85 1026.74 1039.71 1029.71 1008.75 1003.33 1009.05 uncertainty 33.00 33.00 33.00 33.00 33.00 33.00 33.00 33.00 33.00 P (MPa) 962.94 852.89 701.62 928.87 998.33 864.59 703.73 744.71 725.41 P (kbar) 9.63 8.53 7.02 9.29 9.98 8.65 7.04 7.45 7.25 uncertainty (kbar) 1.70 1.70 1.70 1.70 1.70 1.70 1.70 1.70 1.70 187
Geothermobarometry Host: Clinopyroxene
SAMPLE MS169D-01 MS169C-40 MS169C-37 MS169C-35 MS169C-33 MS169C-32 MS169C-31 MS169C-30 MS169C-29
Physical-chemical conditions
T (°C) 1026.78 993.87 1023.05 1024.27 1027.68 1020.90 1019.34 1007.86 1013.46 uncertainty 33.00 33.00 33.00 33.00 33.00 33.00 33.00 33.00 33.00 P (MPa) 887.49 593.06 898.20 901.76 963.95 807.13 788.15 804.16 872.38 P (kbar) 8.87 5.93 8.98 9.02 9.64 8.07 7.88 8.04 8.72 uncertainty (kbar) 1.70 1.70 1.70 1.70 1.70 1.70 1.70 1.70 1.70 188
Geothermobarometry Host: Clinopyroxene
SAMPLE MS169C-18 MS169C-17 MS169C-16 MS169C-15 MS169C-13 MS169C-12 MS169C-11 MS169C-05 MS169B1-58e
Physical-chemical conditions
T (°C) 1014.31 1010.54 1011.61 1034.52 1024.93 1025.17 1036.31 1031.13 1031.24 uncertainty 33.00 33.00 33.00 33.00 33.00 33.00 33.00 33.00 33.00 P (MPa) 896.68 838.40 793.89 982.06 972.56 919.80 992.38 989.65 847.35 P (kbar) 8.97 8.38 7.94 9.82 9.73 9.20 9.92 9.90 8.47 uncertainty (kbar) 1.70 1.70 1.70 1.70 1.70 1.70 1.70 1.70 1.70 189
Geothermobarometry Host: Clinopyroxene
SAMPLE MS169B1-58d MS169B1-58c MS169B1-58b MS169B1-58a MS169B1-56 MS169B1-48 MS169B1-35 MS169B1-26
Physical-chemical conditions
T (°C) 1030.87 1031.67 1029.05 1028.72 1024.34 1029.11 1024.08 1012.20 uncertainty 33.00 33.00 33.00 33.00 33.00 33.00 33.00 33.00 P (MPa) 829.16 851.56 808.74 817.01 909.41 948.72 902.27 696.06 P (kbar) 8.29 8.52 8.09 8.17 9.09 9.49 9.02 6.96 uncertainty (kbar) 1.70 1.70 1.70 1.70 1.70 1.70 1.70 1.70 190
Geothermobarometry Host: Clinopyroxene
SAMPLE MS169B1-23 MS169B1-22 MS169B1-18 MS169B1-17 MS169B1-15 MS169B1-14 MS169B1-13 MS169B1-08
Physical-chemical conditions
T (°C) 977.45 1018.74 1032.25 1004.44 1010.88 1024.84 1015.09 972.20 uncertainty 33.00 33.00 33.00 33.00 33.00 33.00 33.00 33.00 P (MPa) 347.65 952.54 1105.11 740.98 781.70 918.30 853.06 287.94 P (kbar) 3.48 9.53 11.05 7.41 7.82 9.18 8.53 2.88 uncertainty (kbar) 1.70 1.70 1.70 1.70 1.70 1.70 1.70 1.70 191
Geothermobarometry Host: Clinopyroxene
SAMPLE MS169B1-07 MS169B1-06 MS169B1-05 MS169B1-04 MS169A-65 MS169A-64 MS169A-61 MS169A-60
Physical-chemical conditions
T (°C) 1020.03 1023.66 1009.98 1014.77 1035.50 1021.90 1006.35 1022.39 uncertainty 33.00 33.00 33.00 33.00 33.00 33.00 33.00 33.00 P (MPa) 874.78 881.57 776.47 831.24 958.65 913.49 787.46 797.57 P (kbar) 8.75 8.82 7.76 8.31 9.59 9.13 7.87 7.98 uncertainty (kbar) 1.70 1.70 1.70 1.70 1.70 1.70 1.70 1.70 192
Geothermobarometry Host: Clinopyroxene
SAMPLE MS169A-57 MS169A-56 MS169A-55 MS169A-54 MS169A-53 MS169A-52 MS169A-49 MS169A-47 MS169A-34
Physical-chemical conditions
T (°C) 1013.16 1030.70 1013.82 1022.04 1010.68 1019.62 1033.71 1023.88 1017.39 uncertainty 33.00 33.00 33.00 33.00 33.00 33.00 33.00 33.00 33.00 P (MPa) 808.93 1004.39 817.37 901.66 824.42 898.95 960.82 964.38 799.40 P (kbar) 8.09 10.04 8.17 9.02 8.24 8.99 9.61 9.64 7.99 uncertainty (kbar) 1.70 1.70 1.70 1.70 1.70 1.70 1.70 1.70 1.70 193
Geothermobarometry Host: Clinopyroxene
SAMPLE MS169A-32 MS169A-31 MS169A-30 MS169A-18 MS169A-10 MS114A-70 MS114A-69 MS114A-53 MS114A-52
Physical-chemical conditions
T (°C) 1016.46 1019.70 1011.66 1007.20 1025.41 972.31 980.47 959.03 971.51 uncertainty 33.00 33.00 33.00 33.00 33.00 33.00 33.00 33.00 33.00 P (MPa) 898.43 945.80 773.05 792.79 950.96 1017.77 1111.71 888.01 977.71 P (kbar) 8.98 9.46 7.73 7.93 9.51 10.18 11.12 8.88 9.78 uncertainty (kbar) 1.70 1.70 1.70 1.70 1.70 1.70 1.70 1.70 1.70 194
Geothermobarometry Host: Clinopyroxene
SAMPLE MS114A-48 MS114A-26 MS114A-04 MS114A-03 MS114A-01 MS113A-71 MS113A-70 MS113A-59 MS113A-50
Physical-chemical conditions
T (°C) 967.84 963.98 964.20 966.43 973.26 940.07 952.60 942.64 944.37 uncertainty 33.00 33.00 33.00 33.00 33.00 33.00 33.00 33.00 33.00 P (MPa) 975.58 930.58 944.20 995.21 932.79 1081.68 1118.04 1103.06 1131.26 P (kbar) 9.76 9.31 9.44 9.95 9.33 10.82 11.18 11.03 11.31 uncertainty (kbar) 1.70 1.70 1.70 1.70 1.70 1.70 1.70 1.70 1.70 195
Geothermobarometry Host: Clinopyroxene
SAMPLE MS113A-49 MS113A-46 MS113A-45 MS113A-24 MS113A-19 MS113A-18 MS113A-17 MS113A-15 MS113A-14
Physical-chemical conditions
T (°C) 942.22 925.93 935.25 951.28 948.31 950.53 946.24 936.29 936.31 uncertainty 33.00 33.00 33.00 33.00 33.00 33.00 33.00 33.00 33.00 P (MPa) 1100.93 983.85 979.31 1143.10 1097.97 1089.01 1112.50 1073.50 1109.69 P (kbar) 11.01 9.84 9.79 11.43 10.98 10.89 11.12 10.73 11.10 uncertainty (kbar) 1.70 1.70 1.70 1.70 1.70 1.70 1.70 1.70 1.70 196
Geothermobarometry Host: Clinopyroxene
SAMPLE MS113A-13 MS113A-12 MS113A-11 MS113A-10 MS113A-09 MS113A-08 MB07-167_C4R MB07-167_C4Cb
Physical-chemical conditions
T (°C) 931.38 932.25 931.61 937.83 932.78 949.99 1185.33 1168.11 uncertainty 33.00 33.00 33.00 33.00 33.00 33.00 33.00 33.00 P (MPa) 1005.77 1006.41 985.25 998.58 965.50 1077.57 1014.45 901.71 P (kbar) 10.06 10.06 9.85 9.99 9.66 10.78 10.14 9.02 uncertainty (kbar) 1.70 1.70 1.70 1.70 1.70 1.70 1.70 1.70 197
Geothermobarometry Host: Clinopyroxene
SAMPLE MB07-167_C4C MB07-167_C3Cb MB07-167_C3C MB07-145_CC1B MB07-145_CC1 MB07-141_CR4B
Physical-chemical conditions
T (°C) 1175.98 1180.35 1182.11 1057.28 1052.49 1232.39 uncertainty 33.00 33.00 33.00 33.00 33.00 33.00 P (MPa) 972.92 987.02 991.25 726.22 717.86 1103.16 P (kbar) 9.73 9.87 9.91 7.26 7.18 11.03 uncertainty (kbar) 1.70 1.70 1.70 1.70 1.70 1.70 198
Geothermobarometry Host: Clinopyroxene
SAMPLE MB07-141_CR4 MB07-141_CC4C MB07-141_CC4B MB07-141_CC4 MB07-028_C1Cb MB07-028_C1C
Physical-chemical conditions
T (°C) 1247.11 1266.71 1265.82 1269.56 1045.12 1037.48 uncertainty 33.00 33.00 33.00 33.00 33.00 33.00 P (MPa) 1223.85 1385.57 1344.91 1388.49 663.89 561.19 P (kbar) 12.24 13.86 13.45 13.88 6.64 5.61 uncertainty (kbar) 1.70 1.70 1.70 1.70 1.70 1.70 199
Geothermobarometry Host: Clinopyroxene
SAMPLE MB07-017_CR3 MB07-017_CR2 MB07-017_COR2 MB07-017_CC55T9 MB07-017_CC55T8 MB07-017_CC55T7
Physical-chemical conditions
T (°C) 1105.33 1088.60 1103.90 1076.59 1082.12 1081.13 uncertainty 33.00 33.00 33.00 33.00 33.00 33.00 P (MPa) 743.20 584.41 756.14 447.49 512.41 504.52 P (kbar) 7.43 5.84 7.56 4.47 5.12 5.05 uncertainty (kbar) 1.70 1.70 1.70 1.70 1.70 1.70 200
Geothermobarometry Host: Clinopyroxene
SAMPLE MB07-017_CC55T6 MB07-017_CC55T5 MB07-017_CC55T4 MB07-017_CC55T3 MB07-017_CC55T2
Physical-chemical conditions
T (°C) 1088.71 1100.64 1103.43 1089.81 1087.05 uncertainty 33.00 33.00 33.00 33.00 33.00 P (MPa) 616.39 698.81 702.35 583.17 555.02 P (kbar) 6.16 6.99 7.02 5.83 5.55 uncertainty (kbar) 1.70 1.70 1.70 1.70 1.70 201
Geothermobarometry Host: Clinopyroxene
SAMPLE MB07-017_CC55T14 MB07-017_CC55T13 MB07-017_CC55T12 MB07-017_CC55T11 MB07-017_CC55T10
Physical-chemical conditions
T (°C) 1087.03 1107.36 1077.08 1066.31 1074.96 uncertainty 33.00 33.00 33.00 33.00 33.00 P (MPa) 524.45 746.73 449.76 315.80 420.45 P (kbar) 5.24 7.47 4.50 3.16 4.20 uncertainty (kbar) 1.70 1.70 1.70 1.70 1.70 202
Geothermobarometry Host: Clinopyroxene
SAMPLE MB07-017_CC55T1 MB07-017_CC52C MB07-017_CC52B MB07-017_CC52 MB07-017_CC51B MB07-017_CC51
Physical-chemical conditions
T (°C) 1072.32 1091.13 1088.24 1079.28 1088.92 1079.85 uncertainty 33.00 33.00 33.00 33.00 33.00 33.00 P (MPa) 342.01 637.37 601.11 473.10 625.69 497.33 P (kbar) 3.42 6.37 6.01 4.73 6.26 4.97 uncertainty (kbar) 1.70 1.70 1.70 1.70 1.70 1.70 203
Geothermobarometry Host: Clinopyroxene
SAMPLE MB07-017_CC3 MB07-017_CC2 MB06-827_C5R MB06-827_C5C
Physical-chemical conditions
T (°C) 1100.90 1096.40 859.36 873.18 uncertainty 33.00 33.00 33.00 33.00 P (MPa) 771.23 709.63 824.68 1026.46 P (kbar) 7.71 7.10 8.25 10.26 uncertainty (kbar) 1.70 1.70 1.70 1.70