Which of the following is a result of a change in pressure?

a. Frost wedging

b. Oxidation

c. Exfoliation

d. Chemical feathering

The answer is C. The type of weathering that occurs due to changes in pressure drop is a mechanical type. Exfoliation is one type of mechanical weathering where rocks weather by peeling off in sheets. Rocks underneath are under high pressure from underlying rocks. Also, these rocks are experiencing progressively lower pressure from overlying rocks. This creates tension due to unbalance force. Crack formation relieved this tension which will eventually result to exfoliation.