1. n. [Geology, Geochemistry, Shale Gas]
A rock rich in organic matter which, if heated sufficiently, will generate oil or gas. Typical source rocks, usually shales or limestones, contain about 1% organic matter and at least 0.5% total organic carbon (TOC), although a rich source rock might have as much as 10% organic matter. Rocks of marine origin tend to be oil-prone, whereas terrestrial source rocks (such as coal) tend to be gas-prone. Preservation of organic matter without degradation is critical to creating a good source rock, and necessary for a complete petroleum system. Under the right conditions, source rocks may also be reservoir rocks, as in the case of shale gas reservoirs.
See related terms: argillaceous, basin, bitumen, coal, critical moment, generation, geochemistry, hydrocarbon, hydrocarbon kitchen, immature, kerogen, lacustrine, limestone, marine, maturity, migration, natural gas, overmature, petroleum system, pinch-out, pinch-out, play, postmature, primary migration, prospect, pyrolysis, secondary migration, sedimentary basin, sequence stratigraphy, shale, swamp, vitrinite, vitrinite reflectance