Part Two II › Division III III › Section 232 232

Features Produced by Geomorphic Processes Acting on the Earth’s Surface

Subject Outline

AThe action of the hydrosphere and atmosphere on the Earth's surface features
- 1The process of weathering: the disintegration and alteration of rocks at or near the Earth's surface
- 2Soil formation as a result of weathering
  - aProcesses and factors in soil formation [see also 354.A.2.b.]
  - bClassification and distribution of soils
  - cSoil crusts
  - dSoil erosion and deterioration
- 3Gravitational processes: earth movements on slopes
- 4Fluvial processes [see also 126.F.3.]
  - aEntrainment and transport of materials
  - bErosion, deposition
  - cThe sediment yield of drainage systems
  - dThe formation of hillslopes
- 5Eolian processes
  - aTransportation of rock debris by wind
  - bEffects of wind transport
  - cDeposition by wind: formation and migration of dunes, the role of vegetation
  - dWind action and the works of humankind
- 6Marine processes
  - aErosion and deposition of coastal materials by waves and currents
  - bTransport of sediment by density flows
- 7Glacial processes: erosion, transport, deposition, glacial loading and unloading, periglacial processes [see also C.6., below]
- 8Lacustrine processes
  - aErosion and deposition by waves and currents
  - bSedimentation in lakes
  - cEffects of flora and fauna on lakes and lake systems [see 354.B.3.a.]
BThe actions of the biosphere, exosphere, and lithosphere upon the Earth's surface features
- 1Biological processes [see also 351]
  - aEffects of plants and organisms on rock weathering and soil formation [see A.1.and A.2.a., above]
  - bEffects of vegetation type and density on sediment yield [see A.4.C., above]
  - cEffects of humankind on the Earth's surface features; e.g., land cultivation, mining, construction of artificial channels and dams [see also 355, 731, 733.B., 734, 736, and 737]
- 2Extraterrestrial processes: the occurrence of meteorite craters [see also 133.A.3.C.]
- 3Volcanic-tectonic processes [see also 212.D.4., 212.G., 231.F., and 241.E.]
CThe characteristic features of the Earth's major environments
- 1The fluvial environment [see also 354.B.3.b.]
  - aDistribution of rivers in nature
  - bDrainage patterns
  - cThe geometry of river systems
  - dStreamflow and fluvial landforms: peak discharge and flooding, river floodplains and terraces, river deltas, ephemeral streams, waterfalls
  - eThe evolution of river systems through geologic time
- 2The lacustrine environment [see also 354.B.3.a.]
  - aLake basins
  - bLake hydraulics: lake currents, surface waves, seiches, effects of wave and current action [see also 222.G.1.]
  - cLakes in arid regions [see C.5., below]
  - dGlacial lakes [see C.6., below]
  - eSwamps, marshes, and bogs
- 3The estuarine environment
  - aThe formation and destruction of estuaries
  - bHydrologic features of estuaries
- 4The marine environment [see also 354.B.4.]
  - aCoastal features resulting from depositional processes
    - iBeaches: materials, morphological features, physical processes
    - iiSand dunes and sandbars
    - iiiRiver deltas [see C.1.d., above]
    - ivCoral reefs [see 231.E.]
    - vLagoons
    - viMarshes [see C.2.e., above]
  - bCoastal features resulting from erosional processes: sea cliffs and related landforms
  - cCoastal features dependent on bedrock type, bedrock structure, or local topography: grottoes, spouting holes, fjords, peninsulas, islands
  - dSubmerged coastal features: the continental shelf and slope, submarine canyons [see 231.C.]
- 5The desert environment [see also 354.A.1.C.]
  - aGeomorphic processes that shape desert landforms
  - bSurficial features of deserts
    - iMountains, plateaus, pinnacles, and similar features
    - iiAlluvial fans: fan-shaped sedimentary deposits bordering highlands from which the sediment was derived
    - iiiPediments: bedrock surfaces fringing desert highlands
    - ivDesert plains, basins, depressions
    - vPlayas, pans, saline flats
    - viSand sheets and sand dunes
  - cDesert boundaries: expansion and contraction of desert areas [see also 223.E.6.]
- 6The glacial environment [see also 354.A.1.d.]
  - aProcesses of glaciation [see A.7., above]
  - bLandforms produced by glacial erosion
    - iRock polish, striations, grooves, and other small-scale features
    - iiGlaciated valleys, cirques, aretes, horns, fjords
    - iiiGlacially eroded rock basins in non-mountainous regions
  - cLandforms produced by glacial deposition
    - iGlacial till, moraines, drumlins, and other landforms of nonstratified drift
    - iiIce-contact deposits, kames, eskers, and other landforms of stratified drift
    - iiiGlaciolacustrine sediments and associated landforms
  - dLandforms produced by periglacial processes
    - iPermafrost
    - iiTalus, rock glaciers, block fields
    - iiiPatterned ground, including stone nets, stripes, and polygons, and features related to the melting of buried ice masses
- 7The polar environment [see C.6., above, and 354.A.1.d.]
- 8The tropical environment: jungles, rain forests [see also 354.A.1.C.]
- 9The temperate environment: woodlands and grasslands [see also 354.A.1.c.]
- 10The subterranean environment: e.g., caves and cave systems [see also 354.A.1.d ]
- 11Karst topography
DBasic concepts in the theory of landform evolution
- 1The concept of uniformitarianism [see also 242.A.2.a.]
- 2The concept of the cycle of erosion
- 3The concept of morphogenetic regions
- 4The concept of dynamic equilibrium