Changes

Production from fractured upper Bakken Shale has been ongoing since the 1980s from several fields in North Dakota including fields such as Bicentennial, Elkhorn Ranch, Buckhorn, Rough Rider, Demores, and Pierre Creek. Production reported by the North Dakota Geological Survey<ref name=ND2010 /> for fractured upper Bakken Shale is approximately 3,714,699 m3 (23 million bbl), with an average GOR from all upper Bakken Shale production of about 426 m3/m3 (2395 scf/bbl).

Production from fractured upper Bakken Shale has been ongoing since the 1980s from several fields in North Dakota including fields such as Bicentennial, Elkhorn Ranch, Buckhorn, Rough Rider, Demores, and Pierre Creek. Production reported by the North Dakota Geological Survey<ref name=ND2010 /> for fractured upper Bakken Shale is approximately 3,714,699 m3 (23 million bbl), with an average GOR from all upper Bakken Shale production of about 426 m3/m3 (2395 scf/bbl).

An independent geologist, Dick Findley, proposed the idea of producible oil in the Middle Member of the Bakken Formation in 1995, leading to the discovery of the giant Elm Coulee field in eastern Montana in 1996 with the first horizontal well drilled in 2000 (Durham, 2009). Taking Findley's idea, independent geologist Michael S. Johnson extrapolated the idea into Mountrail County, North Dakota, which is located on the eastern flank of the oil window based on various investigators.<ref>Meissner, F. F., 1978, Petroleum geology of the Bakken Formation, Williston Basin, North Dakota and Montana, in D. Estelle and R. Miller, eds., The economic geology of the Williston Basin, 1978 Williston Basin Symposium: Billings, Montana, Montana Geological Society, p. 207–230.</ref><ref>Dembicki Jr., H., and F. L. Pirkle, 1985, [http://archives.datapages.com/data/bulletns/1984-85/data/pg/0069/0004/0550/0567.htm Regional source rock mapping using a source potential rating index]: AAPG Bulletin, v. 69, no. 4, p. 567–581.</ref> Although the same facies of the Middle Member as found in Elm Coulee did not extend that far east, the Middle Member was still charged with oil as shown by the discovery well, the 1-36H-Parshall well that flowed 73.6 m3 (463 bbl/day) of 42deg API oil and 3624.5 m3/day (128 mcf/day) with a GOR of 49 m3/m3 (276 scf/bbl). The next well, the 2-36H-Parshall, flowed 140 m3 (883 bbl/day) of oil and 7079 m3 (250 mcf/day) of gas, yielding a GOR of 50.4 m3/m3 (283 scf/bbl). Recent production from Parshall and Sanish fields typically ranges from 318 to 636 m3 (2000–4000 bbl/day) using very long laterals (as much as 3044 m; ~10,000 ft).

An independent geologist, Dick Findley, proposed the idea of producible oil in the Middle Member of the Bakken Formation in 1995, leading to the discovery of the giant Elm Coulee field in eastern Montana in 1996 with the first horizontal well drilled in 2000.<ref>Durham, L. S., 2009, [http://www.aapg.org/explorer/2009/08aug/findley0809.cfm Learning curve continues: Elm Coulee idea opened new play]: AAPG Explorer, August 2009.</ref> Taking Findley's idea, independent geologist Michael S. Johnson extrapolated the idea into Mountrail County, North Dakota, which is located on the eastern flank of the oil window based on various investigators.<ref>Meissner, F. F., 1978, Petroleum geology of the Bakken Formation, Williston Basin, North Dakota and Montana, in D. Estelle and R. Miller, eds., The economic geology of the Williston Basin, 1978 Williston Basin Symposium: Billings, Montana, Montana Geological Society, p. 207–230.</ref><ref>Dembicki Jr., H., and F. L. Pirkle, 1985, [http://archives.datapages.com/data/bulletns/1984-85/data/pg/0069/0004/0550/0567.htm Regional source rock mapping using a source potential rating index]: AAPG Bulletin, v. 69, no. 4, p. 567–581.</ref> Although the same facies of the Middle Member as found in Elm Coulee did not extend that far east, the Middle Member was still charged with oil as shown by the discovery well, the 1-36H-Parshall well that flowed 73.6 m3 (463 bbl/day) of 42deg API oil and 3624.5 m3/day (128 mcf/day) with a GOR of 49 m3/m3 (276 scf/bbl). The next well, the 2-36H-Parshall, flowed 140 m3 (883 bbl/day) of oil and 7079 m3 (250 mcf/day) of gas, yielding a GOR of 50.4 m3/m3 (283 scf/bbl). Recent production from Parshall and Sanish fields typically ranges from 318 to 636 m3 (2000–4000 bbl/day) using very long laterals (as much as 3044 m; ~10,000 ft).

The Parshall field has proven to be a major field covering more than 3840 km2 (950,000 ac). The North Dakota Department of Mineral Resources projects estimated recoverable oil at 3.331 times 108 m3 (2.1 billion bbl), representing less than 1.5% of OIP (Johnson, 2009).

The Parshall field has proven to be a major field covering more than 3840 km2 (950,000 ac). The North Dakota Department of Mineral Resources projects estimated recoverable oil at 3.331 times 108 m3 (2.1 billion bbl), representing less than 1.5% of OIP (Johnson, 2009).

* Darbonne, N., 2010, EOG's Mark Papa: Barnett combo one of the “richest oil deposits we've ever encountered”: Oil and Gas Investor, February 2010: http://www.oilandgasinvestor.com/Headlines/2010/2/item53192.php (accessed March 27, 2010).

* Darbonne, N., 2010, EOG's Mark Papa: Barnett combo one of the “richest oil deposits we've ever encountered”: Oil and Gas Investor, February 2010: http://www.oilandgasinvestor.com/Headlines/2010/2/item53192.php (accessed March 27, 2010).

*  

*  

* Durham, L. S., 2009, Learning curve continues: Elm Coulee idea opened new play: AAPG Explorer, August 2009: http://www.aapg.org/explorer/2009/08aug/findley0809.cfm (accessed November 12, 2010).

*  

*  

*  

* Espitalie, J., M. Madec, and B. Tissot, 1984, Geochemical logging, in K. J. Voorhees, ed., Analytical pyrolysis: Techniques and applications: London, Butterworths, p. 276–304.

* Espitalie, J., M. Madec, and B. Tissot, 1984, Geochemical logging, in K. J. Voorhees, ed., Analytical pyrolysis: Techniques and applications: London, Butterworths, p. 276–304.