QUATERNARY AND GLACIAL GEOLOGY JURGEN EHLERS Geologisches Landesamt, Germany Translated from Allgemeine und historische Quartdrgeologie English version by Philip L. Gibbard JOHN WILEY & SONS Chichester New York Brisbane Toronto Singapore
Contents Preface xi 1 Introduction 1 1.1 Traces of ice ages in the earth's history 1 1.2 Causes of ice ages 5 SECTION I GENERAL QUATERNARY GEOLOGY 2 Glacier Dynamics 11 2.1 Formation of glaciers 11 2.2 Glacier flow 14 2.3 Formation of Alpine-type ice-stream networks 16 2.4 Formation of continental ice sheets 17 2.5 Formation of marine ice sheets 23 2.6 Glacial erosion 24 2.7 Glacial transport 26 2.8 Glacier dynamics as exemplified by the Late Weichselian Scandinavian Ice Sheet 29 2.9 Methods of reconstructing glacier dynamics 32 2.9.1 Landforms 32 2.9.2 Striae 36 2.9.3 Long-axis orientation of clasts 41 2.9.4 Joint systems 45 2.9.5 Thrust directions 45 2.9.6 Moraine elevations 50 SECTION II QUATERNARY DEPOSITS AND LANDFORMS 3 Glacigenic Deposits and Landforms 55 3.1 Deposits of recent glaciers 55 3.1.1 Subglacial till 56
vi Contents 3.1.2 Other morainic deposits 59 3.2 Pleistocene glacigenic deposits 59 3.3 Post-depositional alteration 63 3.4 Glacigenic landforms 64 3.4.1 Drumlins 64 3.4.2 End moraines 67 3.4.3 Ice-decay landscapes 77 3.4.4 Kettle holes 80 4 Meltwater Deposits and Landforms 82 4.1 Discharge of modern glacial streams 82 4.2 Traces of Pleistocene meltwater activity 86 4.2.1 Tunnel channels 87 4.2.2 Buried channels 87 4.2.3 Eskers 92 4.2.4 Sandur plains, delta plains and gravel terraces 93 4.2.5 Kames 101 4.2.6 Ice-dammed lakes 104 4.2.7 Ice-marginal valleys 108 5 Periglacial Deposits and Landforms 110 5.1 Recent periglacial processes 110 5..1 Cryoplanation 114 5..2 Rock glaciers 115 5..3 Cryoturbation 116 5. 1.4 Solifluction 117 5. 5..5.6 Frost fissures and ice wedges Pingos 117 121 5. 1.7 Palsas 124 5..8 String mires 126 5..9 Thufur 126 5.2 Traces of Pleistocene periglacial processes 127 5.2.1 Fluvial processes 133 5.2.2 Aeolian processes 138 6 6.1 6.2 6.3 6.4 Terrestrial Interglacial Environments Vegetation Fauna Weathering and soil formation Human activities 146 146 147 147 153 7 Marine Environment 157 7.1 Sea-level changes 157 7.2 Marine circulation 162 7.3 Marine deposits 164 7.3.1 Deep sea 164
Contents vii 7.3.2 Shelf seas 168 7.4 Coasts 172 8 Methods of Investigating Glacial and Interglacial Deposits 176 8.1 Grain size 176 8.2 Erratics 177 8.3 Fine gravel and coarse sand 181 8.4 Clast morphology 186 8.5 Heavy minerals 187 8.6 Clay minerals 192 8.7 Geochemistry 193 8.8 Micromorphology 196 8.9 Magnetic susceptibility 197 8.10 Seismic investigations 199 8.11 Geophysical logging 201 8.12 Biological remains 204 8.12.1 Macroscopic plant remains 206 8.12.2 Pollen and spores 208 8.12.3 Diatoms 215 8.12.4 Mammals 215 8.12.5 Molluscs 217 8.12.6 Beetles 218 8.12.7 Foraminifera 219 8.12.8 Ostracods 220 SECTION III QUATERNARY STRATIGRAPHY 9 Principles of Stratigraphy 227 9.1 Chronostratigraphy 227 9.2 Lithostratigraphy 227 9.3 Biostratigraphy 228 9.4 Other stratigraphies 228 10 Dating Quaternary Deposits 230 10.1 Oxygen isotopes 231 10.2 Magnetostratigraphy 237 10.3 Radiocarbon dating 238 10.4 Potassium/argon dating 239 10.5 Thorium/uranium dating 240 10.6 Fission-track dating '240 10.7 Thermoluminescence, optical stimulated luminescence and electron spin resonance 241 10.8 Beryllium dating 242 10.9 Amino-acid dating 243 10.10 Varves 244
viii 11 Quaternary Stratigraphy of Northern Europe 11.1 Palaeogeographic situation at the beginning of the Pleistocene 11.2 Subdivision of the Pleistocene in North Germany and the Netherlands 11.3 Praetiglian 11.4 Tiglian 11.5 Eburonian 11.6 Waalian 11.7 Menapian 11.8 Bavelian 11.9 Cromerian 11.10 Elsterian Cold Stage 11.11 Holsteinian Interglacial 11.12 Fuhne Cold Stage 11.13 Wacken Interglacial 11.14 Saalian Cold Stage 11.14.1 Older Saalian Glaciation 11.14.2 Middle Saalian Glaciation 11.14.3 Younger Saalian Glaciation 11.15 Eemian Interglacial 11.16 Weichselian Cold Stage 11.17 Holocene 11.18 Quaternary development of the Baltic Sea 11.18.1 Origin of the Baltic Sea 11.18.2 Postglacial development of the Baltic Sea 12 Quaternary History of the Alps 12.1 Tectonic framework 12.2 Origin of the valleys and basins 12.3 Classic subdivision of the Alpine Quaternary stratigraphy 12.4 Traces of old glaciations 12.5 Uhlenberg Interglacial 12.6 Giinz Complex 12.7 Gunz/Haslach Interglacial 12.8 Haslach Glaciation 12.9 Haslach/Mindel Interglacial 12.10 Mindel Glaciation 12.11 Mindel/Riss Interglacial 12.12 Riss Glaciation 12.13 Riss/Wiirm Interglacial 12.14 Wurmian Cold Stage 12.15 Holocene 13 Quaternary History of North America 13.1 Late Tertiary 13.2 Early Pleistocene 13.3 Pre-Illinoian warm stages Contents 249 249 251 254 254 255 256 257 257 258 261 268 272 272 275 279 282 283 284 290 309 311 311 313 317 317 318 323 325 334 334 335 335 335 336 336 338 341 344 350 352 353 355 357
Contents ix 13.4 Pre-Illinoian glacial stages 358 13.5 Pre-Illinoian/Illinoian Interglacial 359 13.6 Illinoian Glaciation 361 13.7 Sangamonian Interglacial 362 13.8 Wisconsinan Glaciation 365 13.8.1 Early Wisconsinan 365 13.8.2 Middle Wisconsinan 369 13.8.3 Late Wisconsinan 369 13.8.4 The Great Lakes 384 13.9 Holocene 398 14 Quaternary History of the Rivers 401 14.1 River Danube (Donau) 404 14.2 Rhine (Rhein) and tributaries 408 14.3 Thames 414 14.4 The Siberian rivers 419 14.5 Mississippi 424 14.6 Fluvial development during the Holocene 429 15 Loess Stratigraphy 434 SECTION IV PERSPECTIVE 16 Overview 447 17 Outlook 455 References 457 Index 549