Oil Shale
“Locked-in liquid energy”
Oil shale is a fine-grained sedimentary rock rich in kerogen — organic matter that hasn't been buried deep enough or long enough to convert to petroleum. When heated to high temperatures, this kerogen breaks down and releases oil, making oil shale a vast but controversial energy resource.
clay minerals, quartz, kerogen (organic matter), calcite, pyrite, feldspar
Green River Formation (Colorado/Utah/Wyoming, USA), Estonia, Fushun (China), Jordan, Scotland
2-3
The Green River Formation in the western U.S. contains an estimated 4.3 trillion barrels of oil equivalent in its shale — more than all known conventional oil reserves on Earth combined.
Test Your Knowledge
What would need to happen to oil shale's kerogen for it to naturally produce liquid petroleum?
Photo Attribution
Author: David Hiser
License: public domain
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