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13 Cards in this Set
- Front
- Back
Relative Age |
The age of a rock compared to the ages of other rocks |
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Absolute Age |
The number of years since a rock has been formed
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Law of Superposition |
The law that says that all rocks are older than the rock above it and the rock is younger than the rock below it
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Extrusion |
A rock layer that is formed when lava flows onto Earth's surface and hardens
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Intrusion |
A rock layer formed when lava hardens below Earth's surface
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Fault |
A break or crack in Earth's surface where the rocks move
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Unconformity |
A place where old eroded rock touches new rock layers |
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Index Fossil |
Fossils that are widely distributed that lived only during a short time
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Geologic Time Scale |
A record of the geologic life forms and events
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Era |
One of three long periods of time
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Period |
A part of one of the three different eras
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Comet |
A ball of ice and dust that orbits the sun
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Continental Drift |
The slow movement of continents over Earth's surface |