1. adj. [Geology]
The quality of a source rock that makes it more likely to generate oil than gas. The nature of the organic matter (kerogen) in source rocks varies from coaly, plant-like material commonly found in terrestrial source rocks to algal or other marine material that makes up marine source rocks. Marine source rocks are commonly oil-prone.
See: gas-prone, generation, hydrocarbon, kerogen, maturity, source rock