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This work is protected by copyright and other intellectual property rights and duplication or sale of all or part is not permitted, except that material may be duplicated by you for research, private study, criticism/review or educational purposes. Electronic or print copies are for your own personal, non- commercial use and shall not be passed to any other individual. No quotation may be published without proper acknowledgement. For any other use, or to quote extensively from the work, permission must be obtained from the copyright holder/s. The Relationship between Sedimentary History and Geotechnical behaviour of Quaternary Sediments in Holderness Thesis submitted in accordance with the requirement of the University of Keele for the degree of Doctor of Philosophy by Clive Terence Foster, BSc. December, 1985 PAGE/PAGES EXCLUDED UNDER INSTRUCTION FROM UNIVERSITY II ABSTRACT The stratigraphy-, sedimentology and geotechnical properties of the Quaternary sequence in Holderness were examined in detail, with the aim of relating depositional history to observed geotechnical behaviour. Both the Withernsea and Skipsea Till units were found to possess the sedimentary and geotechnical characteristics of a diamict deposited beneath a wet based ice sheet. No evidence could be found for the downwasting of a complex stratified ice sheet as previously proposed for the sequence. Critical state theory was found to accurately predict the reaction of the diamict to shear and was used to predict the behaviour under theoretical stress/environmental situations. An alternative depositional model is proposed which explains the Skipsea - Withernsea Till succession as the product of the slow accretion of basal debris under an active ice stream. The multiple stratigraphy is interpreted in terms of a shift in the east coast flow units, carrying distinct mixes of lithologies"along individual flow lines, within a single ice sheet. The key sections through the Quaternary in Holderness are re- is examined in terms of deposition from an active ice sheet. It concluded that-the Basement Till represents the initial advance of the cold-ice margin and is Devensian in age rather than pre-Devensian as previously proposed. III Acknowledgements Most of the fieldwork upon which this thesis is based was completed during the tenure of an N. E. R. C. studentship held at ther Department of Geography, Keele University. I am particularly grateful to my supervisors, Prof. E. Derbyshire (University of Leicester) and Mr. A. Marsland (Building Research Establishment) for their valuable guidance throughout this project. Thanks also to Dr. A. J. Parsons (University of Keele) who provided many positive and constructive comments during the period of writing up. Assistance with fieldwork and laboratory analysis from Mr. M. Love and Mr. M. Edge both former contemporary research associates, is also gratefully acknowledged. Laboratory facilities were provided by Keele University with extensive onsite assistance granted by the Building Research Establishment at their test site at Cowden. Details and sub-samples from offshore Quaternary sequences were kindly provided by the British Geological Survey with the assistance of Dr. D. Cameron. Thanks also to Mr. T. S. Whittaker representing Holderness Sand and Gravel Ltd. for allowing free access to the sections exposed at the Mill Hill workings. Liverpool University, Department of Geography kindly provided cartographic, photographic and secretarial expertise which helped bring this work to a conclusion. Lastly, very special thanks must go to my wife, Gill, for her tolerance of my long hours of study, for her painstaking typing of this thesis and for her lasting encouragement. IV CONTENTS PAGE Abstract II Acknowledgements III Table of Contents IV List of Figures IX List of Tables XVII List of Plates XVIII Chapter 1 Regional Stratigraphy and Aims 1.1 Introduction 1 1.2 The Holderness Lincolnshire sequence 1 1.3 Vale of York 8 1.4 North-east England 11 1.5 Offshore Quaternary stratigraphy 16 1.6 Morphological features associated with the Late-Glacial 26 1.7 Aims of the Study 29 Chapter 2 Sampling and Data Acquisition 2.1 Introduction 34 2.2 Cowden Test Bed Site 36 2.2.1 Boreholes CS1, CS2, CS3 36 2.2.2 Trenching 42 2.3 Coastal Sections 46 2.4 Inland Sections 48 2.5 Terrestrial borehole records 50 2.6 Offshore borehole records 52 V PAGE Chapter 3 Analytical Methods. Nomenclature 57 3.1 Introduction 58 3.2 Sedimentological analysis 58 3.2.1 Initial description 58 3.2.2 Moisture content (w) 59 3.2.3 Specific gravity (Gs) 59 3.2.4 Soil index properties 60 3.2.5 X-Ray Diffraction 62 3.2.6 Interpretation of mineral species 63 3.2.7 Heavy mineral analysis - 64 3.2.8 Atterberg limits and related parameters 64 3.2.9 Particle size analysis 66 3.3 Geotechnical Testing 68 3.4 Triaxial sample preparation 70 3.5 Details of main triaxial test programme 71 3.5.1 A Tests 71 3.5.2 B Tests 72 3.5.3 C Tests 78 3.6 Additional Tests 3.6.1 ýu =0 Undrained 79 3.6.2 Consolidated Undrained Tests 80 Chapter 4 Diamict Sedimentology & Index Properties Nomenclature 83 4.1 Introduction 84 4.2 Particle size distribution 84 4.3 Development of the weathering profile 103 4.4 Clay mineralogy 111 VI PAGE 4.5 Bulk index properties 113 4.5.1 Bulk density 113 4.5.2 Dry density 115 4.5.3 Porosity 117 4.5.4 Voids ratio and natural moisture content 119 4.5.5 Specific Gravity 122 4.5.6 Atterberg limits 125 4.5.7 Liquidity index 132 4.5.8 Activity 136 Chapter 5 Geotechnical Behaviour Nomenclature 137 5.1 Conditions of in situ stress 139 5.2 Pore pressure coefficient B 144 5.3 Values of Ko 147 5.4 Undrained shear strength (cu) 153 5.5 Pore pressure coefficient A 160 5.6 Apparent cohesion with ýu =0 171 5.7 Effective cohesion and Angle of Internal Friction 178 5.8 One dimensional consolidation 187 5.8.1 Compression Index 189 Chapter 6 Geötechnical and Sedimentological Associations: Current Models Nomenclature 197 6.1 Introduction 197 6.2 Basic considerations 197 6.3 Moisture content/Undrained shear strength 200 6.4 Applicability of the Critical State model to tills 202 6.5 Stress paths for drained and undrained shear 207 6.6 Theoretical behaviour of an overconsolidated play till 212 6.7 Anomalies in the model 220 VII PAGE Chapter 7 A Geotechnical Model for an Active Ice Sheet in Eastern England 221 7.1 Introduction 220 7.2 Initial conditions: Thermal regime and glacier load 222 7.3 Subglacial pressure: Effective stress at the glacier base 224. 7.4 Proposed stress paths for the deposition and subsequent 228 modification of basal till 7.4.1 Subglacial 228 7.4.2 Proglacial 235 7.4.3 Readvance of the ice margin 243 7.4.4 Post glacial period 246 Chapter 8 Application of the Model to the Situation, 246 Characteristics And Observed Geotechnical Behaviour of the Holderness Till Sheet. 8.1 Introduction 247 8.2 Surface geology prior to ice advance 247 8.3 Nature of the ice sheet profile 253 8.4 Equilibrium conditions 261 264 8.5 Formation of the Skipsea/Withernsea till facies 266 8.6 Application of model to borehole results 273 8.7 Additional points Chapter 9 Deposition from an Active Ice Sheet A Re-examination of Regional Stratigraphy 9.1 Introduction 276 9.2 The Skipsea/Withernsea Till facies 276 276 9.2.1 Composite ice sheet 281 9.2.2 Post glacial weathering 284 9.2.3 Active ice sheet model VIII PAGE 9.3 Interpretation of Skipsea/Basement boundary 286 9.4 Sewerby Type locality 291 9.5 Raft , erratics in the Basement Till 294 9.6 Offshore Hoxnian deposits 297 9.7 Age of main advance 313 9.8 Summary of principal conclusions 316 APPENDICES I Particle Size Distribution Appendix Histograms 335 from Borehole CS1, Offshore GH81/52A and Bulk Samples. Appendix II Summary of sedimentological and 342 geotechnical data from boreholes CS1 CS2 and CS3. III Listing Appendix of programme TXANAL which provides 354 both tabulated and graphical effective stress analysis from monitored triaxial tests with pore pressure. Appendix IV Derbyshire, Foster, Love Edge (1983) _ and Pleistocene lithostatigraphy of North-east 359 England: a sedimentological approach to the Holderness sequence. W. C. Mahaney (ed). Symposium on the correlation of Quaternary Chronologies. Geo Books. Appendix V Foster (1985) A Re-examination of the Dimlington Stadial 366 glacigenic sequence in Holderness. Proc. Ist International Conference on Geomorphology. Ix LIST OF FIGURES Chapter 1 PAGE Figure 1.1 Subdivisions of the Quaternary in Holderness after 2 various workers 1.2 General pattern of ice flow lines in the East 6 Coast Region during the Devensian 1.3 Reconstruction of Devensian maximum ice limit and 9 high level phase of Lake Humber (Gaunt 1975) 1.4 Isopach map of total Quaternary thickness in the 15 North Sea (Caston 1977) 1.5 Stratigraphy of the Kirmington buried channel 17 1.6 Interpretation of the Quaternary stratigraphy of 19 the Dogger Bank from borehole and reflection profiles. Vertical exaggeration X10 (From Oele, 1971) 1.8 Litho and chronostratigraphy of Quaternary deposits 25 in the Dutch sector of the North Sea (Oele 1971) 1.9 Sea floor sediments in UK sector south of 50020'N 27 (Caston 1977) 1.7 Sewerby cliff (Gatt 1977) '22 Chapter 2 2.1 Location of study sites, borehole locations 35 and places mentioned in text. 2.2 Cowden trench stratigraphy (South) 44 2.3 Cowden trench stratigraphy (North) 45 47 2.4 Location map showing limits of Withernsea Till cover (Nhdgett and Catt 1978) 2.5 Regional geology showing the site location and 49 limit of "drift" cover 2.6 The sub-drift surface of central and east 51 Lincolnshire and Holderness showing the Kirmington buried channel (Straw 1979) 2.7 BGS Vibrocore cover in the Spurn map area 53 2.8 Location of rotary cored boreholes drilled in the 55 offshore area by BGS in 1982 Chapter 3 PAGE 3.1 X-Ray diffraction pattern.