1. n. []

The vertical distance from the apex of a structure to the lowest structural contour that contains the structure. Measurements of both the areal closure and the distance from the apex to the lowest closing contour are typically incorporated in calculations of the estimated hydrocarbon content of a trap.

See related terms: anticlinal trap,  unconformity trap

2. n. []

The area, or areal closure, included in the lowest closing contour of a trap. Measurements of both the areal closure and the distance from the apex to the lowest closing contour are typically incorporated in calculations of the estimated hydrocarbon content of a trap.

See related terms: anticlinal trap,  contour,  unconformity trap