Abstract: Reservoir Characterization of Potential Targets for Horizontal Drilling in the Tertiary Green River and Wasatch formations, Bluebell Field, Uintah County, Utah

Carol N. Tripp

The productive interval at Bluebell field consists of thousands of feet of highly fractured, interbedded clastic and carbonate rocks, which were deposited within a fluvial-dominated, lacustrine-deltaic environment. Typically, operators perforate and acidize hundreds of feet of section in each well. By concentrating on a few select zones, completions can be more effective, and production can be increased. Because of extensive fracturing, and low porosity and permeability within these reservoirs, horizontal drilling technology is an excellent option for improving recoverable resources in these zones.

A detailed study within the Roosevelt Unit at Bluebell field was performed to aid in reservoir characterization of the lower Green River and Wasatch formations. Through the use of well drilling and completion histories, stratigraphic cross-sections, and subsurface mapping, zones with horizontal drilling potential have been identified in the lower Green River Formation at depths of approximately 9,000 to 10,000 feet, and in the deeper, overpressured Wasatch Formation at depths exceeding 13,000 feet.

AAPG Search and Discovery Article #90959©1995 AAPG Rocky Mountain Section Meeting, Reno, Nevada