--> --> Abstract: Tensleep Reservoir Study, Oregon Basin Field, Wyoming, by J. T. Morgan, F. S. Cordiner, A. R. Livingston; #90968 (1977).

Datapages, Inc.Print this page

Abstract: Tensleep Reservoir Study, Oregon Basin Field, Wyoming

J. T. Morgan, F. S. Cordiner, A. R. Livingston

Geologists and engineers worked together to define the Tensleep reservoir and to accumulate data that would aid in determining best methods for recovering oil from the reservoir. Since its discovery in 1927, more than 122 million bbl of oil have been produced from the Pennsylvanian Tensleep at the Oregon Basin field.

Assessment of reservoir variables reveals that major reservoir variations are caused by erosion and nonreservoir dolomite. Layers of nonreservoir material separate the Tensleep into zones that perform as discrete reservoirs. Some of these zones have been eroded completely in parts of the field by post-Tensleep streams. Local anomalies and low-magnitude variations are caused by sedimentary structures, small-scale forms of cement, solution vugs, fracturing, and faulting.

Maps of individual zones reveal a complex reservoir distribution which was caused by a combination of original depositional characteristics, postdepositional erosion, and cementation. As little or no cross flow occurs between zones, each zone must be managed separately for optimum oil recovery.

Recognition of reservoir zonation and distribution has led to modification of existing water-injection programs, and provided the basis for planning further development. Incorporation of concepts developed here into the overall reservoir-management program has resulted in significant increases in oil-production rates and will result in increased oil recovery from the Tensleep reservoir.

AAPG Search and Discovery Article #90968©1977 AAPG-SEPM Annual Convention and Exhibition, Washington, DC