explain conditions necessary for deep chemical weathering process
Answers
1. Weathering is a term which describes the general process by which rocks are broken down at the Earth’s surface into such things as sediments, clays, soils and substances that are dissolved in water.
2. The process of weathering typically begins when the earth’s crust is uplifted by tectonic forces. After the physical breakup and chemical decay of exposed rocks by weathering, the loosened rock fragments and alterations products are carried away through the process of erosion.
3. Erosion relies on transporting agents such as wind, rivers, ice, snow and downward movement of materials to carry weathered products away from the source area. As weathered products are carried away, fresh rocks are exposed to further weathering. Over time, that mountain or hill is gradually worn down.
4. There are two types of weathering:
(a) Chemical Weathering results from chemical reactions between minerals in rocks and external agents like air or water. Oxygen oxidizes minerals to alteration products whereas water can convert minerals to clays or dissolve minerals completely.
(b) Physical Weathering is when rocks are broken apart by mechanical processes such as rock fracturing, freezing and thawing, or breakage during transport by rivers or glaciers.