General Awareness World Geography For NDA

Weathering

• Weathering refers to the disintegration and decay of rocks in still under the influence of elements of weather such as changes in temperature, moisture and atmospheric gases.

• Isolation, frost, rainwater, ;atmospheric gases and the organisms are considered the chief agents of weathering.

There are three types cf weathering :

(i) Physical Weathering (or mechanical weathering)

(a) It involves rock disintegration without any change in the chemical constituents of the rocks.

(b) The factors responsible for physical weathering arc temperature change, crystallisation of water into ice, the pressure release mechanism.

(ii) Chemical Weathering : It involves the decomposition due to chemical changes. There arc various chemical processes, which cause chemical weathering such as solution, oxidation,, carbonation, hydration, hydrolysis and chelation.

(iii) Biological Weathering Plants and animals including man largely control it.

It is divided into three types such as

(a) Faunal weathering

(b) Floral weathering

(c) Anthropogenic weathering

 
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