Montana Bakken Montana Natural Energy | Oil & Gas Production

The Bakken Formation

The Bakken Shale Oil field, which stretches down from Canada into North Dakota and Montana, could hold 3.65 billion barrels in oil reserves which would be the largest finding in U.S history next to the Oil fields in Alaska. This oil shale formation is located in the Williston Basin according to the U.S. Geological Survey. Bakken formation is a rich deposit that the U.S. Geological Survey calls the largest continuous oil accumulation it has ever assessed.

The Bakken Formation is one of the largest contiguous deposits of oil and natural gas in the United States. It is an interbedded sequence of black shale, siltstone and sandstone that underlies large areas of northwestern North Dakota, northeastern Montana, southern Saskatchewan and southwestern Manitoba. The Bakken was deposited within the Williston Basin and is Late Devonian to Early Mississippian in age.

The Bakken Formation consists of a lower shale member, a middle sandstone member and an upper shale member. The shales are organic-rich and of marine origin. They are rich source rocks for oil and natural gas. All three members of the Bakken Formation have been known to yield oil and natural gas.

Just a few years ago the Bakken was considered a marginal to submarginal resource because the oil and gas are locked in a rock formation with a low permeability. However, advances in drilling and recovery technology such as horizontal drilling and hydrofracturing have transformed it into a viable resource. The formation is expected to provide a boost to our energy supply and economy. Much of the oil in the Bakken requires additional advances in technology or higher oil prices for profitable recovery.

The USGS Assessment for the Bakken Formation estimated mean undiscovered volumes of 3.65 billion barrels of oil, 1.85 trillion cubic feet of associated / dissolved natural gas, and 148 million barrels of natural gas liquids in the United States portion of the Bakken Formation. These resources are contained within both conventional and unconventional reservoirs.

The Bakken Formation

The Bakken Formation underlies large areas of northwestern North Dakota, northeastern Montana, southern Saskatchewan and southwestern Manitoba.

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Modern Drilling in the Bakken

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The Bakken Formation became a viable resource because of advances in drilling and recovery methods. Horizontal drilling enables wells to have a much longer "pay zone" than a traditional vertical well.

Hydrofracturing produces porosity in the rock unit that facilitates movement of oil or gas to the well. Together, these methods allow a single well to drain a much larger volume of rock and more efficiently recover the oil and gas resource.