Comment: 09:07 - 09:40 (00:33)
Source: Annenberg/CPB Resources - Earth Revealed - 15. Weathering and Soils
Keywords: "J. Lawford Anderson", mineral, "Earth's surface", quartz, hematite, "iron oxide", rust, temperature, pressure, weathering
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Our transcription: Only a few minerals are really stable at the earth's surface.
The mineral, quartz, for example; hematite, iron oxide, is stable -- that's rust, it's stable the earth's surface; but most minerals are not.
Most minerals form at temperatures very different than 25 degrees centigrade in one atmosphere of pressure.
The minerals that are the most unstable at the earth's surface and weather the fastest are those that are formed at the highest temperatures.
Minerals that are the most stable and will weather the least are those that formed initially at the lowest temperatures.
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Geology School Keywords
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