Seismic data can be used for statistical estimation of the exploration outcomes of specific prospects. This study involves estimation of the outcome probabilities for complexly faulted domal structures in the Tabasco basin of Mexico. Seismic reflection times were contoured by computer throughout much of the Tabasco basin, employing a special computer algorithm to accommodate the complex system of faults. Computer contouring was deemed essential for systematic statistical treatment.

The probability estimates relating presence of petroleum to seismically interpreted structures involved combining two independent sources of uncertainty, namely, uncertainty in the contoured representation of the structures, and uncertainty as to the presence of petroleum in view of the specific attributes of the structures. Residuals from third-degree polynomial trend surfaces were used to measure the size and shape of structures. The procedures developed could be used in other regions.