Reservoir Description in Three Dimensions: Case Study from the Sockeye Field, Santa Barbara Channel

WRACHER, MICHAEL, Venoco Inc., Santa Barbara, CA; KAREN CHRISTENSEN, Venoco Inc., Santa Barbara, CA; JEFF LAWTON, Venoco Inc., Santa Barbara, CA; GARY ORR, Venoco Inc., Santa Barbara, CA

The Sockeye Field is one of two producing fields located along the southern margin of the Santa Barbara Channel. Productive formations range from the marine Eocene Juncal, through the fluvial Oligocene Sespe, marine Topanga, and finally the siliceous shales of the Monterey Formation. The Santa Barbara Channel has a complex deformational history with much of this history manifest at Sockeye including, mid-Tertiary extension, and late Tertiary through Quaternary compression.

We describe the Sockeye Field in three dimensions by integrating 3-D seismic, open-hole log, mudlog, and other interpretive data into an EarthVision based earth model. Completion intervals and their status have also been brought into the model. Venoco, Inc. uses this 3-D reservoir description during ongoing reservoir management and planning.

The early Sockeye interpretation, synthesized during field acquisition, answered important questions about the Monterey Formation, such as rock volume. As our understanding increased, we were directed towards potential recompletion opportunities and model resolution was refined for the specific opportunity areas. The original interpretation contained six major reservoir units; our current interpretation contains over thirty geologic layers. Additional model complexity allows Venoco, Inc. to plan well recompletions, design new well paths, run various volume cases, and to hypothesis about complex and/or poorly imaged geologic phenomena.

AAPG Search and Discovery Article #90911©2000 AAPG Pacific Section and Western Region Society of Petroleum Engineers, Long Beach, California