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10 Cards in this Set
- Front
- Back
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Principle of Uniformitarianism |
The present is the key to the past |
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The law of Superposition |
In an undisturbed sequence of sedimentary rocks, the oldest rocks must be on the bottom |
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Half-Life |
the time taken for half of the parent atom to decay to decay to daughter elements |
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How old is the Earth? |
4.6 billion years |
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Relative time scales |
place and events in their general sequence of formation |
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Silicates |
Most abundant group of minerals and make up 95% of the earths crust and upper mantle. |
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Cleavage |
The tendency of a mineral to break along a plane of weakness |
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Hardness |
measure of the resistance of a mineral to abrasion |
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How are minerals classified? |
Mafic and Felsic |
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Most common elements made during the big bang |
Hydrogen and Helium |
