The Bakken region is located in the northwestern section of North Dakota. As of August 2015, 10 counties that border Montana cover the Bakken oil-producing shale deposits. Parts of three other counties include the eastern edge of the oil deposits.
According to the U.S. Geological Survey, there are 3.65 billion barrels of oil in the Bakken shale deposit, an area that covers portions of two Canadian provinces and parts of Montana and North Dakota. In North Dakota, the Bakken deposits lie more than a mile below Divide, Burke, Renville, Williams and Mountrail, as well as below McKenzie, Golden Valley, Billings, Dunn and Stark counties. The eastern portions of Ward, McLean and Mercer counties also include Bakken deposits.