Correct Answer - Option 3 : Loess
The soils formed at a place may be transported to other places by agents of transportation, such as water, wind, ice and gravity.
1) Water transported Soils: Flowing water is one of the most important agents of transportation of soils. Swift running water carries a large quantity of soil either in suspension or by rolling along the bed.
The size of the soil particles carried by water depends upon the velocity.
All type of soils carried and deposited by water are known as alluvial deposits. Deposits made in lakes are called lacustrine deposits. Such deposits are laminated or varved in layers. Marine deposits are formed when the flowing water carries soils to ocean or sea.
2) Wind transported Soils: Soil particles are transported by winds. The particle size of the soil depends upon the velocity of wind. Soils deposited by wind are known as aeolian deposits.
Collapsible soil is those for which there is a decrease in volume on the addition of water. Loess is one such example. Loess is a silt deposit made by wind. These deposits have low density and high compressibility. The bearing capacity of such soils is very low.
3) Glacier-Deposited Soils: Glaciers are large masses of ice formed by the compaction of snow. As the glaciers grow and move, they carry with them soils varying in size from fine grained to huge boulders.
Drift is a general term used for the deposits made by glaciers directly or indirectly. Deposits directly made by melting of glaciers are called till. The soil carried by the melting water from the frint of a glacier is termed out-wash.
4) Gravity deposited soil: These are soils transported through short distances under the action of gravity. Colluvial soils such as talus have been deposited by the gravity. Talus consists of irregular, corase particles. It is a good source of broken rock pieces and coarse grained soils for many engineering works.
