Abstract: Integrated 3-D Seismic and Petroleum Engineering Reservoir Characterization of a Sealing Fault System, Hambert Field Terry Sandstone Reservoir, Denver Basin
BENSON, ROBERT D., and THOMAS L. DAVIS
Hambert field is located in Weld County, Colorado, approximately five miles (8 km) south of the city of Greeley, in the central portion of the Denver Basin. The Upper Cretaceous Terry Sandstone member of the Pierre Shale produces oil and gas at a depth of 4500 feet (1370 m). The gross thickness of the Terry is approximately 150 feet (46 m). The production is from fractures in a low permeability zone, approximately 60 feet (18 m) thick, near the base of the Terry.
The P-wave and S-wave seismic data collected over the eastern edge of Hambert field, together with petroleum engineering techniques, have successfully mapped compartmentalization within the Terry Sandstone, reservoir. The compartmentalization is controlled by both lithologic and structural components of the reservoir. Identification of reservoir compartments, and their relationship to recurrent fault movement f and sedimentation, is critical to characterizing the reservoir. Faulting is more prevalent than originally believed, and significantly affects development of the reservoir. Fracture zones, associated with faulting, enhance production in this reservoir by increasing permeability and reservoir volume.
This study demonstrates the importance of understanding the complexity of a reservoir early in its production history. The entire development of Hambert field would have been modified if the extent of the compartmentalization of the reservoir had been recognized early. The number and placement of development wells could have maximized production while lowering development costs.
AAPG Search and Discovery Article #90946©1997 AAPG Rocky Mountain Section Meeting, Denver, Colorado