Aeolian Sands and Sandstones
Total Page:16
File Type:pdf, Size:1020Kb
Durham E-Theses Aeolian sands and sandstones Steele, Richard Patrick How to cite: Steele, Richard Patrick (1981) Aeolian sands and sandstones, Durham theses, Durham University. Available at Durham E-Theses Online: http://etheses.dur.ac.uk/7504/ Use policy The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that: • a full bibliographic reference is made to the original source • a link is made to the metadata record in Durham E-Theses • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders. Please consult the full Durham E-Theses policy for further details. Academic Support Oce, Durham University, University Oce, Old Elvet, Durham DH1 3HP e-mail: [email protected] Tel: +44 0191 334 6107 http://etheses.dur.ac.uk AEOLIAN SANDS AND SANDSTONES RICHARD PATRICK STEELE, B.Sc. Collingwood College A thesis submitted to the University of Durham for the degree of Doctor of Philosophy Department of Geological Sciences December 1981 VOLUME I OP II The copyright of this thesis rests with the author. No quotation from it should be published without his prior written consent and information derived from it should be acknowledged. ii VOLUME I; CONTENTS Page List of figures viii Abstract xvii Preface xix CHAPTER 1 MODERN ERGS 1 Section 1.1 Climate and vegetation 1 Definition of the term desert 1 Causes of deserts 2 Vegetation in ergs 3 Section 1.2 The dimensions of ergs 4 Section 1.3 Erg development 7 Constraints on the growth of ergs 7 A model for the development of ergs 11 Section 1.4 Ergs and associated facies 14 Summary 16 CHAPTER 2 THE WIND, BEDPORMS AND CROSS-BEDDING 18 Introduction 18 Section 2.1 The wind 18 Section 2.2 Aeolian bedforms and their origins 20 General 20 Ripples 23 Megaripples 29 Dunes and draa 3"1 Section 2.3 Cross-bedding 37 General 37 The generating bedforms 38 The cross-bedding pattern 43 Section 2.4 Implications for palaeocurrents 54 Section 2.5 The analysis of cross-bedding 57 iii Page Summary 60 CHAPTER 3 THE LAMINATION AND GRAIN CHARACTERISTICS OF AEOLIAN SANDS 61 Introduction 61 Section 3.1 Lamination 61 Section 3«2 Grain size 71 Section 3«3 Grain shape and surface texture 84 Summary 86 CHAPTER 4 THE LOWER PERMIAN SETTING IN BRITAIN 88 Introduction 88 Section 4.1 Stratigraphic terminology 88 Section 4»2 The Permian climate in Britain 89 Section 4-3 Erosion, deposition and tectonics ^ CHAPTER 5 THE YELLOW SANDS - INTRODUCTION AND SEDIMENTARY STRUCTURES 94 Section 5«1 The lithology and definition of the formation 94 Exposures 97 Section 5«2 Form and internal structures 99 Distribution and thickness 98 Descriptions of localities 101 Palaeocurrents 126 Summary of the sedimentary features at the top of the formation 127 Summary 130 CHAPTER 6 THE DEPOSITION OF THE YELLOW SANDS 131 Introduction 131 Section 6.1 Bedforms, bounding surfaces and wind regime 131 The palaeocurrent diagram 133 Wind regime 136 iv Page Sand-sheet deposits 139 Bounding surfaces 143 Dune size 145 The rate of deposition of the formation 146 Section 6.2 The Zechstein transgression 147 Previous work 147 The evidence of the sedimentary structures 149 Mass "balance and palaeogeographical considerations 153 Discussion 154 The history of development of the Yellow Sands erg 156 CHAPTER 7 THE LAMINATION, GRAIN SIZE CHARACTERISTICS AND PETROLOGY OF THE YELLOW SANDS 158 Section 7.1 Lamination and grain size characteristics 158 Introduction 158 Lamination 158 The grain size data - description 159 The grain size data - deductions and interpretation 165 Section 7.2 The petrology of the Yellow Sands 167 Introduction 167 Methods 168 Colour 170 Framework grains 171 Pigmenting and associated minerals 174 Authigenic dolomite 181 Grain overgrowths 182 Calcite cement 182 Other minerals 186 Porosity and compaction 187 Section 7«3 The provenance and diagenesis of the Yellow Sands Provenance The diagenetic sequence Summary CHAPTER 8 THE BRIDGNORTH SANDSTONE Section 8.1 Introduction, stratigraphy and distribution Section 8.2 Sedimentary structures Introduction Description and interpretation of the cross-bedding Other structures Section 8.3 Lamination and grain size Methods Lamination Grain size characteristics Section 8.4 Petrography and diagenesis Colour and general characteristics Framework grain composition Grain shape and surface texture Porosity and compaction Pigment and pore-lining clays Feldspar dissolution and overgrowths Pore-filling clays Other minerals Paragenesis Section 8.5 A comparison with the Yellow Sands Summary CHAPTER 9 THE PENRITH SANDSTONE vi Page Introduction 239 Section 9»1 Stratigraphy and location 239 General 239 Palaeogeography 241 Section 3.2 Sedimentary structures 242 Cross-bedding 242 Lamination 244 Other structures 244 Section 9-3 Petrography 247 Previous work 247 Composition 249 Pigment and pore-lining clays 250 Quartz overgrowths 252 Other minerals 253 Po rosity and compaction 254 Section 3.4 Interpretation of the diagenesis 255 Summary CHAPTER 10 THE SIGNIFICANCE, CHARACTERISTICS AND IDENTIFICATION OP AEOLIAN SANDS 260 Introduction 260 Section 10.1 The palaeogeographic and stratigraphic significance of aeolian sandstones in the U.K. 260 Stratigraphy 260 Wind regime and climate 263 Section 10.2 The characteristics of aeolian sandstones 266 Cross-bedding 266 Lamination 277 Grain size characteristics 282 Grain shape and surface texture 285 Diagenesis 286 Facies relationships 290 vii Page Reservoir properties 292 Section 10.3 The identification of aeolian sandstones 293 General 293 Aeolian v. shallow marine sands 294 Identifying criteria and their pitfalls 299 Summary 303 APPENDIX OTHER AEOLIAN SANDSTONES IN THE U.K. 305 REFERENCES 311 viii VOLUME II: CONTENTS DIAGRAMS, PHOTOGRAPHS, TABLES AND ENCLOSURES Pa,ge CHAPTER 1 MODERN ERGS FIG. 1.1 World map showing deBerts and ergs 2 FIG. 1.2 Size histogram of ergs 3 FIG. 1.3 Ergs, subsidence and tropospheric flow 4 FIG. 1.4 Weathering and deflation rates 5 FIG. 1.5 Erg models 6 FIG. 1.6 Facies in tectonically Stable deserts 7 FIG. 1.7 Facies in tectonically active deserts 8 CHAPTER 2 THE WIND, BEDFORMS AND CROSS-BEDDING FIG. 2.1 Types of aeolian bedform 10 FIG. 2.2 Wind ripples 11 FIG. 2.3 Ripple patterns and the ballistic mechanism 12 FIG. 2.4 The rebound of saltating grains 13 FIG. 2.5 The behaviour of saltating grains where the path length has a finite standard deviation 13 FIG. 2.6 Bedform pattern types 14-15 FIG. 2.7 Transverse dunes on sinuous transverse draa in the Rub' al Khali, Saudi Arabia 16 FIG. 2.8 Wind regime and bedform patterns 17 FIG. 2.9 Migrating and climbing draa in two dimensions 18 FIG. 2.10 Factors governing first order Bet thickness 19 FIG. 2.11 Factors governing third order set thickness 20 FIG. 2.12 Preservation in linguoid and lunate patterns 21 FIG. 2.13 Cross-bedding pattern produced by a sinuous transverse bedform migrating and climbing uniformly 22 FIG. 2.14 Cross-bedding pattern developed by two superposed orders of sinuous transverse bedform 23 FIG. 2.15 The development of mod if icotioa surfaces 24 ix Page FIG. 2.16 Cross-bedding pattern produced by two superimposed orders of sinuous transverse bedform with partly random behaviour 25-26 FIG. 2.17 Bedform shapes and potential palaeocurrent azimuths 27 CHAPTER 3 THE LAMINATION AND GRAIN CHARACTERISTICS OF AEOLIAN SANDS FIG. 3.1 Wind-ripple lamination 29 FIG. 3.2 Sandflow lamination 30 FIG. 3*3 Sand-sheet lamination y\ CHAPTER 4 THE LOWER PERMIAN SETTING IN BRITAIN FIG. 4«1 Permian stage names and time scale 33 FIG. 4' Late Permian continent reconstruction 34 FIG. 4«3 Palaeowinds from the British Lower Permian 35 CHAPTER 5 THE YELLOW SANDS - INTRODUCTION AND SEDIMENTARY STRUCTURES FIG. 5-1 Distribution of the Yellow Sands and Basal Breccias 37 F G. 5-2 Lower Permian palaeogeography and isopachs, NW Europe 38 FIG 5-3 Comparative Rotliegendes sequences 39 FIG. 5«4 The subsurface distribution of the Yellow Sands 4° FIG. 5*5 Specimen of the pebble lag layer, Cullercoats 41 FIG. 5.6 Base of the Yellow Sands, Tynemouth 42 FIG. 5.7 Base of the Yellow Sands, North Hylton 43 FIG. 5.8 Overthrust laminae, McCall's Quarry 44 FIG. 5.9 View of the top of the Yellow Sands, McCall's Quarry 45 FIG. 5.10 Lingula credneri at McCall's Quarry 46 FIG. 5.11 ?Permophorus costatus at McCall's Quarry 47 FIG. 5.12 The north face of Hetton Downs Quarry 48 FIG. 5-13 Minor ridges on the top of the Yellow Sands, Hetton Downs Quarry 49 X Page FIG. 5.14 West face of Sherburn Hill Sand Pit 50 FIG. 5.15 Crime Rigg Quarry 51 FIG. 5-16 Measured sections of the top of the Yellow Sands, Sherburn Hill Sand Pit 52 FIG. 5.17 Deformation, Sherburn Hill Sand Pit 53 FIG. 5.18 Bioturbation, Sherburn Hill Sand Pit 54 - FIG. 5.19 Top of the Yellow Sands, Bowburn Quarry 55 FIG. 5.20 Top of the Yellow Sands Bowburn Quarry 56 FIG. 5-21 ?Permophorus costatus. Bowburn Quarry 57 FIG. 5.22 Deformation, Bowburn Quarry 58 FIG. 5'23 Deformation, Bowburn Quarry 59 FIG. 5-24 Deformation of the planar-bedded zone, Bowburn Quarry 60 FIG, 5«25 Cross-bedding and red sand, Bowburn Quarry 61 FIG. 5-26 Measured sections of the top of the Yellow Sands, Quarrington Hill Quarry 62 FIG. 5-27 Possible water-lain cross-lamination, Quarrington Hill Quarry 63 FIG.