Interference testing in reservoirs with conductive faults or fractures

This paper addresses interference testing in reservoirs with conductive faults allowing fluid flow along and across the fault plane. An altered skin region around fault thrusts is also included. It is found that the classical line-source solution does not apply. When active and observation wells are located across a fault, the interference behavior resembles that of a hydraulically fractured well with bilinear how characteristics. However, different flow regimes are developed on the pressure derivative when the well pairs are situated at the same side: initially, the basic line-source behavior; then, constant pressure effect from the fault represented by a negative unit-slope line; and, finally, bilinear flow. Interference type curves for various regions in the reservoir are developed and practical guidelines are provided for interpretation of these tests. Field data from an interference test in a faulted carbonate reservoir are analyzed and fault parameters are estimated.