An integrated 3-D reservoir characterization at Riverton Dome Field, Wyoming

Abstract

Riverton Dome is a prime example of a mature Rocky Mountain oil and gas field that has benefited from new drilling based on a recent 3-D seismic survey. The field was discovered in 1949 through surface geology and seismic (Hinton, 1957; Borgerding, 1989) and was acquired by Snyder Oil Corporation (SOCO) in 1993. In 1998 SOCO acquired a 38-mi2 3-D seismic survey over Riverton Dome Field with funding from Belco Energy, Tom Brown Incorporated, and the U.S. Department of Energy to determine reservoir distribution, structural configuration, and compartmentalization. The survey was acquired with fractionated bins to image the steep dip on the flanks of the structure as a cost-effective alternative to using a smaller bin size. It was processed independently by two vendors. Results were very similar, providing confidence in the high quality of the data. Geologic maps were integrated with various seismic attributes to define reservoir models and to project reservoir trends beyond the current field. As a result of the Riverton Dome 3-D study, three successful wells were drilled in the Muddy Sandstone and additional opportunities in multiple Upper Cretaceous reservoirs and the Tensleep Sandstone were identified. Riverton Dome, a structurally controlled, mature oil and gas field is on the Wind River Indian Reservation, approximately six miles southeast of the town of Riverton in the southwestern portion of Wyoming's Wind River Basin (Figure 1). A series of thrust-faulted anticlines strikes NNW-SSE, parallel to the large Wind River Mountain thrust to the west. These features formed in the Late Cretaceous-Paleocene during the early stages of the Laramide orogeny (Keefer, 1965, 1970; Gries, 1983). Both Riverton Dome Field and Beaver Creek Field to the south are on the crest of a north-plunging asymmetrical anticline bounded on the west by a steeply dipping thrust fault that originates in basement. The …