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Soil transport and deposit by gravity are called...
Talus
Drift
Loess
Aeolian
Talus
Talus, also known as colluvium, refers to the accumulation of rock fragments and soil particles at the base of a cliff or steep slope due to the direct influence of gravity. This process occurs when weathering causes rock material to detach, and gravitational forces cause it to fall and deposit without the aid of water, ice, or wind.
Talus, also known as colluvium, refers to the accumulation of rock fragments and soil particles at the base of a cliff or steep slope due to the direct influence of gravity. This process occurs when weathering causes rock material to detach, and gravitational forces cause it to fall and deposit without the aid of water, ice, or wind.
╧Д=c+╧ГnтАЛtan(╧Х) тАФ Mohr-Coulomb failure criterion determining the stability of slope materials
The process is driven by the gravitational potential energy of weathered material on a steep gradient. As rock breaks down due to mechanical weathering (such as frost wedging), the slope angle exceeds the angle of repose for the loose material, causing mass wasting (rockfall). The resulting pile, or talus slope, typically maintains a characteristic steep angle consistent with the internal angle of friction of the coarse debris.
Talus deposits are characteristically coarse-grained, angular, and poorly sorted due to the nature of gravitational transport.
The slope angle of a talus deposit is generally equal to the angle of internal friction of the granular material.
Gravity-deposited soils are technically classified as 'Colluvial' deposits.
Unlike alluvial or glacial soils, talus is not subjected to significant mechanical abrasion during transport.
Provides easily accessible crushed rock/aggregate for local construction purposes.
Acts as a natural indicator of active physical weathering in mountainous terrain.
High susceptibility to rockfalls, posing significant hazards to infrastructure built at the base of slopes.
Poor foundation characteristics due to loose, non-homogeneous composition.
Geological mapping and hazard assessment for landslide-prone mountainous regions.
Source of raw material for base course construction in remote highway projects.
Option B (Drift): General term for all deposits of glacial origin.
Option C (Loess): Soil deposited by wind, consisting mainly of silt-sized particles.
Option D (Aeolian): Broad classification for soils transported and deposited by wind action.
The internal angle of friction for typical talus slopes ranges from 30┬░ to 40┬░.
A is correct тАФ Talus (or Colluvium) represents soil and rock fragments transported solely by the action of gravity.
Always distinguish between 'Alluvial' (water-borne), 'Glacial' (ice-borne), 'Aeolian' (wind-borne), and 'Colluvial' (gravity-borne) soils to identify the depositional environment in soil mechanics problems.