Horizontal Wells Improve Oil Recovery in 100 Year Old Pennsylvanian Sandstone Reservoirs in Northeast Oklahoma and Southeast Kansas

Bob Westermark and June Schmeling.  Grand Resources, Inc., Tulsa, Oklahoma  [email protected]

This paper discusses the results of applying a multi-disciplinary approach to selecting horizontal-well candidates in 100-year-old Pennsylvanian oil fields in northeast Oklahoma and southeast Kansas. By combining a rigorous team effort that includes geological depositional interpretations, rock-mechanics evaluations, and reservoir-simulation studies with cost-effective drilling and completion technologies, Grand Resources, Inc. has drilled projects yielding economic success. The range of reservoir conditions where this approach has been applied is discussed, and the results of the various projects are candidly presented.

This series of horizontal-well projects was based upon a grant received by the Department of Energy (DOE) to conduct a field pilot test for a horizontal waterflood in a Bartlesville sandstone reservoir. This project will be briefly reviewed (this project has been the topic of several technical papers), with updated production results. The other horizontal projects presented are the expansion of the DOE pilot area in the Bartlesville sandstone in eastern Osage County, Oklahoma, and two in the Tucker sandstone formation: one near Chanute, Kansas, and the other just north of Tulsa, Oklahoma.

All of the projects have utilized a short-radius rotary-steerable drilling system. All have been drilled underbalanced, logged, and open-hole completed with pumping equipment placed in the vertical section of the well. Open-hole logging through the short-radius curve to the end of the lateral provides an excellent description of reservoir properties, identifying high oil-saturation compartments and detecting the presence and orientation of natural fractures.