Crosscutting and the Principle of Superposition
- Newer rocks are deposited on top of older rocks. The newer rocks cover up the older rocks.
- For sedimentary or volcanic rocks, the oldest layers are therefore on the bottom and the youngest layers are on the top. We call this "The Principle of Superposition" (super = top).
- When one type of rock cuts through other rocks, it had to form after the rocks that it cuts. (You can't cut a cake until you have baked a cake).
GeoSleuth Murder Mystery
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