Faulted structural surfaces present difficult problems for the computer mapper, though several solutions are possible. In this paper, I present a method whereby the fault plane is treated as if it were a structural surface. The method uses fault picks, oil/water contact data, directional survey data, and reservoir data. The data are manipulated and mapped with a commercially available mapping package using standard gridding, editing, and data-to-grid manipulations. The resulting fault grids can be integrated with grids of structural surfaces, used as boundary surfaces, or used to develop fault gaps on structure maps.

Fault-surface modeling is most applicable to large oil fields with many wells. Several advantages have been realized, including accurate fault locations at all horizons and accurate predicted fault penetrations for new well locations. When new penetrations are encountered, they can be used to update the fault plane and then the revision can be employed to correct the structure maps. Multiple interpretations for the fault surface can be tested for validity. The techniques and products described were developed for the Wilmington oil field in Long Beach, California.