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  • USGS names Bakken play the largest oil accumulation in Lower 48

    D. M. Cohen

    In April 2008, the US Geological Survey completed a long-awaited re-assessment of the US portion of the Bakken Formation, a late Devonian-early Mississippian formation of the Williston Basin of Montana, North Dakota and Saskatchewan, Canada. The agency estimated the region’s undiscovered, technically recoverable oil resources to be between 3.0 billion and 4.3 billion bbl, making the Bakken play the largest oil accumulation it has ever assessed in the Lower 48. Technically recoverable resources are those that can be recovered using existing industry technologies and practices. This number does not take into account economic factors, as reserve figures do; nor should it be confused with the total in situ resources. The latter was estimated by USGS in 2001 to be between 200 and 400 billion bbl. The mean-case estimate of 3.6 billion bbl represents a 25-fold increase compared with USGS’s 1995 estimate of 151 million barrels of oil.

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2013 Fracturing Technology

2013 Fracturing Technology