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GLG/220: Physical Geology


sunset in a country environment
Cockburn explains James Hutton's idea of geological cycles. His discovery of geological unconformities helped scientists understand the geological time scale and how life evolved.
earths layers
This video introduces the concept of geological time (also called deep time); relative age dating of rock via the principles of stratigraphic superposition, original horizontality, and cross-cutting; absolute age dating by radioactive decay; the chemical elements, heavy and light, that make up the planet; and Earth’s three main layers: crust, mantle, and core.

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