Which weathering process is mechanical?
A. solution.
B. Carbonation
C. Hydration
D. Thermal expansion

D. Thermal expansion

Explanation:

MECHANICAL WEATHERING

can be defined as the gradual disintegration of rock into smaller particles which later turn into soil. when mechanical weathering occurs, it doesn't change the chemical composition of the rock. mechanical weathering are caused by abrasion by ice water, thermal expansion, root of trees growing on the rock.

THERMAL EXPANSION

This is a mechanical  process of weathering. during the day when there is high temperature and hits the rock surface, the rock absorbs heat expands . at night when the temperature drops the rock contrast. Repeated action of expansion and contraction results in gradual breakdown of rock to form soil.

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