External processes

External processes are geomorphic activities that originate from forces outside the Earth's surface.
These processes are also called exogenic processes.
They include weathering, erosion, transportation, and deposition.
External processes are driven by solar energy, gravity, and the hydrological cycle.
Weathering is the breakdown of rocks into smaller particles through physical, chemical, or biological means.
Physical weathering includes processes like frost action, thermal expansion, and exfoliation.
Chemical weathering involves the alteration of rock composition through reactions like oxidation, hydrolysis, and carbonation.
Biological weathering occurs due to the actions of plants, animals, and microorganisms.
Weathering contributes to the formation of soil and other sediments.
Erosion is the removal and transport of surface materials by agents like water, wind, ice, and gravity.
Water erosion creates landforms such as river valleys, canyons, and gullies.
Wind erosion leads to features like sand dunes and yardangs, common in arid regions.
Glacial erosion forms U-shaped valleys, fjords, and other glacial features.
Coastal erosion shapes sea cliffs, arches, and stacks through wave action.
Mass wasting, or mass movement, is the downslope movement of materials under gravity, forming landslides, debris flows, and rockfalls.
Transportation refers to the movement of eroded materials by natural agents like rivers, glaciers, and winds.
Rivers transport sediments as bedload, suspended load, and dissolved load.
Glaciers carry large boulders and fine debris, forming features like moraines and drumlins.
Wind carries fine particles, leading to the formation of loess deposits.
Deposition occurs when transported materials are dropped due to a decrease in energy.
Depositional landforms include river deltas, alluvial fans, and sandbars.
In deserts, deposition forms features like sand dunes and playas.
Glacial deposition creates landforms like moraines, eskers, and outwash plains.
Coastal deposition leads to features like beaches, spits, and barrier islands.
External processes continuously reshape the Earth's surface, balancing the forces of uplift and erosion.
Fluvial processes, driven by rivers, dominate in humid regions and shape floodplains, levees, and terraces.
Aeolian processes, caused by wind, are significant in arid and semi-arid regions.
Glacial processes are active in polar and high-altitude regions, carving landscapes and depositing sediments.
Marine processes shape coastal landforms through wave action, tides, and ocean currents.
Karst topography forms in regions with soluble rocks like limestone, leading to caves, sinkholes, and stalactites.
Human activities like deforestation, mining, and construction accelerate erosion and alter natural processes.
Understanding external processes helps in managing soil erosion, landslides, and other environmental challenges.
Climatic factors, such as temperature and precipitation, influence the intensity and type of external processes.
Topography affects the rate and pattern of weathering, erosion, and deposition.
Vegetation helps stabilize soils, reducing erosion and enhancing deposition.
External processes are essential for creating diverse landforms and maintaining ecological balance.
They play a crucial role in the formation of natural resources like soil, sedimentary rocks, and fossil fuels.
Weathering and erosion contribute to the geochemical cycle, recycling minerals and nutrients.
External processes are interlinked with internal processes, shaping Earth's dynamic landscape.
Long-term changes in external processes are influenced by factors like climate change and sea-level variations.
Monitoring and managing these processes are vital for sustainable development and disaster mitigation.
Natural landscapes owe their diverse forms to the combined effects of external processes over geological timescales.

External processes

Category

Questions