Bakken Formation of the Williston Basin

Through the use of technology, U.S. oil and natural gas operators are converting previously uneconomic oil and natural gas resources into proved reserves and production.

The Bakken Formation of the Williston Basin is a success story of horizontal drilling, fracturing, and completion technologies. The recent, highlyproductive oil field discoveries within the Bakken Formation did not come from venturing out into deep uncharted waters heretofore untapped by man, nor from blazing a trail into pristine environs never

open to drilling before. Instead, success came from analysis of geologic data on a decades-old producing area, identification of uptapped

resources, and application of the new drilling and completion Technology necessary to exploit them.

In short, it came from using technology to convert unconventional resources into reserves.

Location

The Williston Basin is in the north central United States, underlying much of North Dakota, eastern Montana, northwestern South Dakota, and southern Saskatchewan and Manitoba, Canada (Figure 1).

The Bakken Formation can be encountered throughout the Williston Basin. It is 11,000 feet deep in the depocenter (see Glossary) of the basin in the southwest corner of North Dakota. The depth of the Bakken

rises to 4,500 feet deep on the eastern edge of the basin, and up to 3,100 feet deep (950 meters) on the northern edge, across the Canadian border in Manitoba and Saskatchewan.

The Bakken Formation was formally described (named) by geologist J.W. Nordquist in 1953. His samples came from the Amerada Petroleum - H.O. Bakken #1 well on the Nesson Anticline in Williams

County, North Dakota. Henry Bakken was the surface owner where the well was drilled.1 The current U.S. development activity in the Bakken Formation is located in Richland County, Montana,

and McKenzie, Golden Valley, and Billings Counties, North Dakota. The largest discovery to date within

the Bakken Formation is the Elm Coulee Field of Richland County, Montana.

Energy Information Administration, Office of Oil and Gas, Reserves and Production Division, November 2006

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