LANDFORMS AND THEIR EVOLUTION
Contents
1. Introduction 80
2. Landform and Landscape 80
3. Causes 80
4. Landforms and Scale: Crustal Orders of Relief 80
5. Evolution of Landform 80
6. Landform Classification 81
7. Fluvial Landforms (Latin: Fluvius=River) 81
7.1. Action of a River/Stream 81
7.1.1. Erosion 82
7.1.2. Transportation 82
7.1.3. Deposition 83
7.2. River rejuvenation 88
7.2.1. Knick point 89
7.2.2. River Terrace 89
7.2.3. Incised or Entrenched Meanders 90
7.3. Significance of work of River 90
7.4. Features of Overview 91
7.4.1. Erosional Landforms 91
7.4.2. Depositional Landforms 91
7.4.3. Erosional and Depositional Landforms 91
8. Coastal landforms 91
8.1. Coastal processes: Tides, Current and Waves 91
8.1.1. Sea Waves mechanism 92
8.2. Coastal erosion 92
8.3. Erosional Features 92
8.3.1. Cliffs and wave-cut-platforms 92
8.3.2. Capes and bays 93
8.3.3. Cave, Arch and Stack 93
8.3.4. Blow holes and Geos 94
8.4. Depositional Features 94
8.4.1. Wave-Built Platform or Terrace 94
8.4.2. Beaches 95
8.4.3. Bars, Spits and Tombolo 95
8.5. Types of Coasts 96
8.6. Coastlines of submergence 96
8.7. Coastlines of Emergence 96
9. Glacial Landforms 97
9.1. Action of Glacier 97
9.2. The landforms created by glacial erosion 98
9.1.1. Cirque (or Corrie) 98
9.1.2. Arete 98
9.1.3. Pyramidal Peaks 98
9.1.4. Tarn 98
9.1.5. Bergschrund 98
9.1.6. ‘U’ - shaped Valley 99
9.1.7. Hanging Valley 99
9.1.8. Truncated spurs 99
9.1.9. Paternoster lakes 99
9.1.10. Roche Moutonnee 100
9.2. Glacial landforms resulting from deposition 100
9.2.1. Boulder clay or glacial till 100
9.2.2. Outwash deposits 100
9.2.3. Erratics 100
9.2.4. Moraines 100
9.2.5. Outwash plain and Kettles 101
9.2.6. Kames 101
9.2.7. Eskers 101
9.2.8. Drumlins 101
10. Landform by the Action of Wind 102
10.1. Mechanism of wind Action in deserts 102
10.2. Erosional Landforms-Wind 103
10.2.1. Ventifacts or Dreikanter 103
10.2.2. Ventifact 103
10.2.3. Rock Pedestals or Mushroom Rocks 103
10.2.4. Yardangs 104
10.2.5. Zeugens 104
10.2.6. Mesas and Buttes 104
10.2.7. Inselbergs 104
10.3. Depositional Landforms-wind 104
10.3.1. Loess 105
10.4. Fluvial Desert Landforms 105
10.4.1. Wadis 106
10.4.2. Pediments 106
10.4.3. Bahada (Bajada) 106
10.4.4. Playas 106
11. Karst Topography 106
11.1. Erosional landform 107
11.1.1. Sink Holes, Swallow Holes, Dolines and Uvalas/valley sink 107
11.1.2. Lapies 107
11.1.3. Caves 107
11.2. Depositional Landforms 108
11.2.1. Stalactites and Stalagmites 108
12. Economic significance of karst regions 108