>> The Bakken Formation in Montana and North Dakota may contain between 3 and 18 billion barrels. As a comparison, the North Slope of Alaska has produced, over the last 35 years or so, around 16 billion barrels.
By way of comparison, the USA burns about 7 billion barrels per year, the world about 30. 18 billion barrels pushes the time of reckoning off for the USA by less than 3 years. If you produce it over the typical depreciation lifetime of capital equipment (20 years), 18 billion bbl is 900 million bbl/yr or only about 2.5 million bbl/day; the USA imports several times this.
On the other hand, at $150/bbl, 18 billion bbl represents one heaping fsckload of money. That's why there's interest in this; if we were serious about energy, we'd reverse the insane cancellation of the Integral Fast Reactor in 1994. The USA has several HUNDRED years of feedstock for breeder reactors already mined and refined in warehouses (roughly 700 thousand tons of depleted uranium hexafluoride). But there's not going to be major cash-flow in uranium for breeders, no payoffs for pols; the political economy votes for carbon-based fuels.