1. n. [Geology]

A variety of sealed geologic structure capable of retaining hydrocarbons, such as a fault or a fold. Stratigraphic traps form where changes in rock type can retain hydrocarbons.

See: anticlinal trap,  anticline,  fault,  fault trap,  fold,  hydrocarbon,  seal,  stratigraphic trap,  subsalt,  syncline,  trap