Tropical Geomorphology

Contents......Page 8
 Preface......Page 14
PART I THE TROPICAL ENVIRONMENT......Page 16
1.1 Geomorphology in the tropics......Page 18
1.2  Traditional tropical geomorphology......Page 22
1.3  Modernisation of tropical geomorphology......Page 23
1.4 Structure of tropical geomorphology......Page 24
1.5 Structure of the book......Page 26
2.2 A brief introduction to plate tectonics......Page 28
2.2.2 Convergent boundary......Page 31
2.2.3 Transform fault boundary......Page 33
2.2.4 Plate tectonics and landforms......Page 34
2.3 Major landforms across the tropics......Page 35
2.4 Interrelationships: plate tectonics, landforms, erosion and sediment production......Page 42
Questions......Page 44
3.2 Temperature......Page 46
3.3 Wind circulation......Page 47
3.4 Precipitation......Page 49
3.5 Tropical disturbances......Page 52
3.6 Miscellaneous factors......Page 58
3.7 Water balance......Page 59
3.8 Climate and geomorphology in the tropics......Page 62
Questions......Page 63
4.1 Erosion from tropical rainfall......Page 64
4.3 Tropical rain forests......Page 67
4.3.1 Passage of rainwater through tropical rain forest......Page 69
4.4 Tropical deciduous forests, grasslands and deserts......Page 70
4.5 Anthropogenic alteration of the tropical vegetation......Page 72
Questions......Page 73
PART II PROCESS GEOMORPHOLOGY IN THE TROPICS......Page 74
5.1 Introduction......Page 76
5.2.1 Physical weathering......Page 78
5.2.2  Chemical weathering with special reference to the humid tropics......Page 81
5.3 Products of weathering......Page 84
5.3.2  Weathering of common intrusive igneous rocks......Page 86
5.3.3 Weathering of sedimentary rocks......Page 88
5.4. Weathering and vertical zonation......Page 90
5.5 Pans and crusts......Page 92
5.6 Effects of weathering......Page 93
5.7 Tropics and weathering......Page 95
Questions......Page 96
6.1 Properties of a slope......Page 97
6.2 Mass movement on hillslopes......Page 99
6.2.1 Falls......Page 100
6.2.2 Slides......Page 102
6.2.3 Flows......Page 105
6.2.4 Creep......Page 107
6.3 Running water on hillslopes......Page 108
6.4 Storage and transfer of surficial material on tropical slopes......Page 109
6.4.1 Tropical rain forest slopes......Page 110
6.4.2 Steep slopes of hills and low mountains......Page 111
Questions......Page 114
7.2 Water in river channels......Page 116
7.3 Sediment in river channels......Page 119
7.4 Channel geometry......Page 123
7.4.1 Slope of the river......Page 124
7.4.2 Size of the river channel......Page 126
7.4.3 Shape of river channels......Page 128
7.4.4 Channel pattern......Page 130
7.5 Channel network and nodes......Page 134
7.6 River systems of the humid tropics......Page 135
Questions......Page 142
8.1 Fluvial depositional environment......Page 144
8.2 The alluvial valley......Page 145
8.3 The channel alluvium......Page 147
8.4 Bars......Page 150
8.5 Floodplain......Page 151
8.6 Terrace......Page 154
8.7 Valley margins......Page 155
Questions......Page 156
9.2 Characteristics of a large river......Page 158
9.3.1 The physical setting......Page 162
9.3.2 Transfer of water and sediment along the Amazon......Page 164
9.3.3 Morphology of the Amazon River......Page 166
9.4.1 The physical setting......Page 167
9.4.2 Water and sediment......Page 169
9.5 The Ganga–Brahmaputra system......Page 170
9.5.1 The physical setting of the Ganga River......Page 171
9.5.3 Sediment......Page 172
9.5.4 The valley morphology......Page 173
9.5.5 The setting of the Brahmaputra River......Page 174
9.5.6 Hydrology......Page 175
9.5.8 The channel of the Brahmaputra......Page 177
9.6 The Mekong......Page 179
9.6.1 The physical setting......Page 180
9.6.3 Sediment......Page 181
9.6.4 The channel of the Mekong......Page 182
Questions......Page 184
10.1 Introduction......Page 185
10.2 Types of coast......Page 186
10.3.1 Tides......Page 187
10.3.2 Waves......Page 188
10.3.3 Currents......Page 192
10.4 Rocky coasts......Page 194
10.5 Non-rocky coast......Page 196
10.5.1 Beach......Page 197
10.5.3 Barrier island......Page 199
10.7 Coastal tropics......Page 201
10.7.1 Mangrove swamps......Page 202
10.8 Coral reefs......Page 204
10.9 Tropical coasts and time......Page 206
Questions......Page 209
11.1 Introduction......Page 210
11.2 Distribution of deltas in the tropics......Page 211
11.3 Age and evolution of deltas......Page 212
11.4 Delta morphology......Page 216
11.5 Delta sediments and sedimentary structures......Page 217
11.6.1 The background......Page 218
11.6.2 Morphology......Page 220
11.7 Deltas in the tropics: a summary......Page 222
Questions......Page 223
12.1 Arid areas......Page 224
12.2 Geological characteristics of arid lands......Page 225
12.3.1 Desert rainfall......Page 226
12.3.2 Flood generation......Page 227
12.5 The rock desert......Page 230
12.6 Running water in arid lands......Page 231
12.7.1 Aeolian process......Page 238
12.7.2 Aeolian forms of erosion......Page 239
12.7.3 Aeolian forms of deposition......Page 240
Questions......Page 245
13.1 Importance of highlands......Page 247
13.2.1 Glaciation in the Himalaya......Page 249
13.2.2 Glaciation in the Andes......Page 250
13.3.1 Formation of glacial ice......Page 251
13.3.2 The glacial mass balance......Page 252
13.3.3 The mechanics of glacial movement......Page 253
13.4 Glacial forms and processes......Page 255
13.4.2 Cirques......Page 256
13.4.3 Glaciated valleys......Page 257
13.4.4 Glacial deposition......Page 258
13.5.1 Mass movements in the high mountains......Page 261
13.6 Rivers in the tropical mountains......Page 262
13.7 Sediment from tropical mountains......Page 264
13.8 Conclusion......Page 266
Questions......Page 267
14.2 Types of volcano and the related landscape......Page 269
14.2.2 Polygenetic volcanoes......Page 270
14.2.4 A comparison......Page 271
14.3 Lava and pyroclastic deposits......Page 272
14.3.1 Ash fall deposits......Page 274
Ignimbrite......Page 275
Block and ash flow deposits......Page 276
14.4 Volcaniclastic flows: debris avalanches and flows......Page 277
14.5 Landscape on flood basalts......Page 281
Questions......Page 283
15.1 Introduction to karst......Page 285
15.2 Karst in the tropics: the geographical distribution......Page 286
15.3 Karst hydrology......Page 287
15.4 Dissolution of karst rocks......Page 288
15.5 Karst landforms......Page 289
15.5.2 Dolines or sinkholes......Page 290
15.5.4 Karst valleys......Page 292
15.5.5 Cone and tower karsts......Page 293
15.5.6 Caves......Page 294
15.6 Karst in the tropics......Page 296
15.7 Tropical karst as an environment......Page 299
Questions......Page 301
16.1 Introduction......Page 302
16.2 History and structure of the Quaternary......Page 303
16.3 Quaternary glaciation in the tropics......Page 305
16.4 Climate change......Page 307
16.5 Sea-level change......Page 310
16.6 The Ganga River system: Quaternary adjustments......Page 313
16.7 Quaternary changes around the Sunda Shelf......Page 314
16.8 Conclusion......Page 317
Questions......Page 318
PART III ANTHROPOGENIC CHANGES......Page 320
17.1 The beginning......Page 322
17.2.1 Causes of forest destruction......Page 326
17.2.2 Effects of forest destruction......Page 327
17.2.3 Land use changes and sediment yield......Page 328
17.3 Temporal and seasonal patterns of sediment transport......Page 329
17.4 Spatial transfer of sediment......Page 330
17.5 Impoundments along rivers and their effects......Page 334
17.5.1 Downstream effects of dams on alluvial rivers......Page 335
17.5.2 Downstream effect of dams on rivers in rock......Page 337
17.6 Application of geomorphology towards a better environment......Page 338
Questions......Page 339
18.1 Introduction to urban geomorphology......Page 340
18.2 Urbanisation in developing countries......Page 343
18.3.1 Urban geomorphology of Singapore......Page 345
18.3.2 Kingston: the hazard-prone urban landscape......Page 348
18.3.3 Bangkok: flooding and subsidence......Page 350
18.4 The general nature of urban geomorphological problems......Page 352
18.5 Geomorphology and urban management......Page 353
Questions......Page 356
19.1 Climate change and the future......Page 357
19.2.1 Nature of climate change......Page 358
19.2.3 Identifying the changes......Page 359
19.3 Geomorphological adjustments in the tropics from climate and sea-level changes......Page 360
19.4 The noise effect of anthropogenic changes......Page 361
19.5 Tropical geomorphology in the near future......Page 362
Questions......Page 363
References......Page 364
Index......Page 389
Color Plates......Page 402