+Oil shale is a fine-grained [sedimentary rock](/wiki/sedimentary_rock) rich in [kerogen](/wiki/kerogen), a solid organic matter. When heated, this rock yields shale oil, a synthetic petroleum. It represents a vast, unconventional energy resource.
+## See also
+- [Fossil Fuel](/wiki/fossil_fuel)
+- [Shale Oil](/wiki/shale_oil)
+- [Kerogen](/wiki/kerogen)
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