Theory question 103
Rocks and Soil Formation(a) What is rock weathering?
(b) Enumerate three processes involved in rock weathering.
(c) List and discuss briefly the agents of two of these processes.
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(a) Weathering is the breaking down of rocks in place into smaller particles by physical, chemical and biological agents to form soil parent material
(b) Physical (mechanical) weathering; chemical weathering; biological weathering
(c) Any two: Physical – temperature (alternate heating and cooling cracks rocks), water (freezing, running water abrades), wind (sand blasting); Chemical – hydration, hydrolysis, oxidation, carbonation, solution change minerals; Biological – plant roots grow into cracks and split rocks, burrowing animals, micro-organisms and lichens release acids, man's activities
Define, list three processes, then explain the agents of two of them.