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 consis, kollakas kuni peaaegu must settekivim, mis sisaldab peamiselt veekogude madalamatest organismidest pärinevat vesinikurikast orgaanilist ainet kerogeeni. Termiliselt lagunedes annab kerogeen suure õlis, kivim, mille orgaanilise aine õliandvus on >20%