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Factors that influence weathering

Answer Text:
Factors That Influence Weathering
i. Climate
- Different areas with different climatic elements experience different types of weathering e.g. block disintegration are experienced in arid areas while frost action is experienced in temperate regions and mountainous regions of tropics.
ii. Topography
- Weathering is faster on steep slopes than on gentle slopes because weathered material is washed away quickly exposing
the rock once again to agents while on gentle slopes materials remain in one position shielding the rock from weathering agents.
iii. Nature of rocks
- Dark coloured rocks absorb more heat than light coloured ones hence break faster due to excessive expansion and contraction.
- A rock with different minerals may disintegrate faster due to differential expansion and contraction of minerals.
- A well jointed rock will break faster because physical and
chemical agents can penetrate faster e.g. by freezing and thawing.
- Fine textured rocks have a large surface area on which chemical processes can act e.g. Limestone.
iv. Biological organisms
- Bacteria facilitate rotting of organic matter producing organic acids which reacts with some minerals causing the rock to break up.
- Plant roots and burrowing animals penetrate rocks resulting in cracks providing passage for agents such as water to act on rocks.
- People accelerate the rate of weathering by exposing rocks buried deep below by digging, blasting and drilling.