oil shale

oil shale, any sedimentary rock containing various amounts of solid organic material that yields petroleum products, along with a variety of solid by-products, when subjected to pyrolysis—a treatment that consists of heating the rock to above 300 °C (about 575 °F) in the absence of oxygen. The liquid oil extracted from oil shale, once it is upgraded, creates a type of synthetic crude oil that is commonly referred to as shale oil. Oil produced from...