Comment: 16:19 - 17:04 (00:45)
Source: Annenberg/CPB Resources - Earth Revealed - 15. Weathering and Soils
Keywords: weathering, soil, "parent rock", granite, "sandy soil", quartz, clay, feldspar, basalt, iron, permeability, "fertile soil", vegetation
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Our transcription: The nature of a soil is determined partly by what sort of parent rock it develops from, because this is its prime material.
If the parent rock is granite, it decomposes into a sandy soil made up of quartz grains.
Clay in the soil comes from the weathering of feldspars.
Such soil is usually permeable and can easily nourish vegetation.
A fine grained rock, such as basalt, decomposes more rapidly to clay minerals than iron compounds.
Basalt forms soil that is generally darker and less permeable than granitic soil, but still fertile.
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Geology School Keywords
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