Скачать 0.73 Mb.
Improved Recovery Demonstration for Williston Basin Carbonates -- Class II
Luff Exploration Company
Red River Formation Several fields
@ 9,500 ft Bowman County, ND
Ordovician Age Harding County, SD
Ratcliffe Formation Richland County, MT
@ 8,500 ft.
Mississippian Age Williston Basin
waterflooding is technically and economically feasible in Red river and Ratcliffe formations in the Williston Basin.
Incremental Production: Three new wells penetrated by-passed reserves. Initial production per well averaged 190 bbl oil per day. Extrapolation of production data indicates more than 600,000 bbl of oil will be produced, in aggregate, by these wells.
Expected Benefits and Applications: If techniques are successful, the project will add nearly 6000,000 bbl of increased oil reserves. Application of techniques by other operators could boost recovery from their fields by about one-third. Prolong the economic life of existing oil wells. 3D seismic surveys will help identify bypassed oil areas. Lateral completion methods will improve oil productivity and injectivity to water. This will improve economics of infill drilling for additional primary reserves and new waterflood projects. The project will test lateral completion techniques, including high pressure jetting lance technology and short-radius lateral drilling to enhance completion efficiency. Additional locations containing probable by-passed reserves were identified within the 3-D seismic surveys.
Accomplishments: Four half-day workshops were presented in Denver and Billings in 1996-97. Descriptions and images of cores are published on an Internet site under the Petroleum Technology Transfer Council, Rocky Mountain Region, home page. Three wells were drilled based on study of 3D seismic surveys in Bowman Co., North Dakota. These wells encountered by-passed oil in complex carbonate reservoirs at locations near old wells. The new wells were completed with an average initial rate of 190 bbl oil per day. Recoverable reserves from the demonstration wells are expected to equal or exceed reserves produced by their old neighbors. Cumulative production from the oil wells is 637,000 bbl oil. In addition to the reserves developed by the project wells, further development potential has been identified within the 3D seismic areas and will be tested in the near future. Thirty-day water injection tests were performed in both a vertical and horizontal well in Harding Co., SD. Data from these tests were used to predict long-term injection and oil recovery. These predictions precipitated a 12-month injection pilot. Several technologies were evaluated for re-entry drilling of horizontal drain holes through casing. Tests of short and medium-reach jetting lance technologies were unsuccessful. Reservoir depths of 8500 to 9500 ft are greater than appropriate for the mechanical capability of these tools. Steered, mud-motor drilling was mechanically successful. A re-entry lateral completion in the Ratcliffe was mechanically successful but did not increase production. A new horizontal well was drilled between two vertical wells that produce from a partially depleted Red River reservoir. Production and injection tests in this well indicate two to three times productivity of nearby vertical wells. A topical report was written that discusses these activities and their results. Reservoir characterization studies of Ratcliffe and Red River reservoirs were completed. Two 3D seismic surveys were obtained in the Red River area of Bowman Co., ND. These surveys revealed the complexity of reservoir porosity and were used to target wells for by-passed oil. A 3D seismic survey and a special shear-wave seismic survey were obtained in the Ratcliffe area of Richland Co., MT. The shear-wave survey was a failure. Fracture characterization in the Ratcliffe includes acquisition of an oriented core and a special electrical log at North Sioux Pass Field, Richland Co., MT. Topical reports covering geological and engineering characterization studies discuss reservoir characteristics, producibility problems and improved-recovery technologies. Additional locations containing probable by-passed reserves were also identified within the 3D seismic surveys obtained during the project term. Luff Exploration Company is continuing to apply techniques developed during the project and plans to drill more locations from the 3D seismic surveys. Application of techniques by other operators could boost recovery from some fields by about one-third. If techniques are successful, the project will add nearly 600,000 bbl of increased oil reserves.
Publications: (1) Sippel, Mark A. and Michael L. Hendricks. 1997. "Geological and Engineering Characterizations of the Upper Red River Formation in the Southwest Williston Basin." SPE 38371, Society of Petroleum Engineers, Rocky Mountain regional meeting, Casper, Wyoming. May 18-21, 1997. (2) Sippel, Mark A. 1997. "Characterization of Red River Reservoirs from 3D Seismic at Cold Turkey Creek Field.", American Association of Petroleum Geologists, Rocky Mountain sectional meeting held in Denver, Colorado. August 24-27, 1997. (3) Mark Sippel, 1998, "Exploitation of Reservoir Compartments in the Red River Formation, Southern Williston Basin": RMAG Compartmentalized Reservoirs in Rocky Mountain Basins, Rocky Mountain Association of Geologists. (4) Case studies from project can be found
under Rocky Mountain PTTC Homepage http://www.mines.edu/research/PTTC/lecrr/lecrr/lecrr01.htm and http://www.mines.edu/research/PTTC/lecrc/lecrc/lecrc01.htm
Recent/Upcoming Technology Transfer Events: (1) Sippel, Mark A., 1997. "Characterization of Red River Reservoirs from 3D Seismic at Cold Turkey Creek Field", The Denver Geological Study Group, July 24, 1997. (2) Sippel, Mark A., Kenneth D. Luff, and Michael L. Hendricks. 1997. "Red River Reservoir Study - A Success Story." Half-day workshop presented with Petroleum Technology Transfer Council, Rocky Mountain Region in Denver, Colorado and Billings, Montana, November 10 and 14, 1997. (3) Sippel, Mark A. and Kenneth D. Luff. 1997. "Demonstrating Improved Recovery in Williston Basin Carbonates", Emerging Technologies Energy Conference, Independent Petroleum Association of America held in Houston, Texas, November 17, 1997. (4) Bailey, Jim and Mark Sippel, 1998. "Characterization of Red River Reservoirs from 3D Seismic at Cold Turkey Creek Field", 4th Annual 3-D Seismic Symposium, Rocky Mountain Association of Geologists and The Denver Geophysical Society, Denver, Colorado, February 18, 1998. (5) Core and petrographic study of Red River and Ratcliffe reservoirs on the Internet at the PTTC Rocky Mountain Region home page. (6) Core and petrographic study of Red River and Ratcliffe reservoirs on CD-ROM to be distributed by the PTTC Rocky Mountain Region. (7) Mark Sippel, "Pressure Transient Results from a Red River B Horizontal Well": SPE Reservoir/EOR, May 19, 1998, Denver, CO.
Project Status: Project complete. Final report and three topical reports published July 1998.
Project Update December 2002: Follow up 3-D seismic work identified targets in the Red River formation and 4 successful wells were drilled.