Summary

The flux of hydrocarbons across compartmentalizing faults is controlled by several parameters including the pressure gradient created by a producing well, fault thickness, and the permeability distribution along the fault. Two phase numerical flow simulations are used to study these characteristics based on different input datasets and parameters. From results of the simulations, we conclude that: 1) for a constant fault area and thickness, pressure support across the fault plane is controlled by the mean permeability of the fault plane. Variance of the permeability population is a second-order effect; 2) fault rapture resulting from large pressure differences across compartments leads to increased pressure support because of the increase in mean permeability across the fault plane; 3) with a well producing at a constant rate, the area of the fault rupture has little effect on the amount of pressure support observed and; 4) in gas reservoirs without significant aquifer influx, mean fault permeability values can be derived from production data by measuring the change from initial reservoir pressure to that at the time of steady-state gas influx.

AAPG Search and Discovery Article #90937©1998 AAPG Annual Convention and Exhibition, Salt Lake City, Utah