1. n. [Geology]

The time of maximum depth of burial of a hydrocarbon source rock. The critical moment is the time of highest probability of entrapment and preservation of hydrocarbons in a petroleum system—after traps form and hydrocarbons migrate into a reservoir and accumulate—and marks the beginning of preservation in a viable petroleum system.

See related terms: accumulation,  generation,  migration,  petroleum system,  preservation,  reservoir,  source rock,  trap