Formation of Soil-Orgin and Types of Soil

Formation of Soil

Soil is an unconsolidated discrete material consisting of solid particles which are produced due to weathering of rocks,decomposition of rocks,decomposition of organic matter etc..The formation of soil process is happened by two process

1.Weathering of Rocks

2.Decomposition of Rocks.

The process of soil weathering involves physical weathering and chemical weathering.The example of products of soil formation by physical weathering are silt,sand and gravel and chemical weathering are clay minerals.

The factors affecting physical weathering are temperature change,pressure change and abrasion and the factors affecting chemical weathering are oxidation,carbonation and hydrolysis.They are called inorganic soils.In chemical weathering orginals are transformed into new minerals by chemical reactions

The decomposition of soil results in the formation of humus and red soil.They are called organic soils.Organic soils are not used in foundation material,because they are extremely compressible.

If the soils are produced at the place of orgin only,they are called residual solids.Residual solids are laterite soil and black cotton soil

If the soils are produced away from the orgin,it is called transported soil.The transportation of soil to other places are by agents.These agents are gravity ,water and wind.

Glacier-Glacier deposited soils

Gravitation-Colluvial soil

Wind-Aeolian soil

River-Alluvial soil

Lakes- Lacustrine soil

Field names of soils

In the above section, soil names are listed based on the medium of transportation.Here we are going the describe the field names of different soils.

Loamy soil-It is a mixture of sand ,silt and clay.

Varve-Its a mixture of silt and clay

Moorum-Its a mixture of gravel and red clay

Bentonite clay-They are formed by decomposition of volcanic ash.