A new US Geological Survey study found that not only is the amount of the natural gas in the upper plains states of North and South Dakota and Montana three time larger than previously reported but that there was twice as much oil in there too.

Here’s the study. It summarizes its findings as:

Using a geology-based assessment methodology, the U.S. Geological Survey estimated mean undiscovered volumes of 7.4 billion barrels of oil, 6.7 trillion cubic feet of associated/dissolved natural gas, and 0.53 billion barrels of natural gas liquids in the Bakken and Three Forks Formations in the Williston Basin Province of Montana, North Dakota, and South Dakota.

The Interior Department explained the significance of this in a press release:

This assessment of both formations represents a significant increase over the estimated mean resource of 3.65 billion barrels of undiscovered oil in the Bakken Formation that was estimated in the 2008 assessment.

“These world-class formations contain even more energy resource potential than previously understood, which is important information as we continue to reduce our nation’s dependence on foreign sources of oil,” said Secretary of the Interior Sally Jewell. “We must develop our domestic energy resources armed with the best available science, and this unbiased, objective information will help private, nonprofit and government decision makers at all levels make informed decisions about the responsible development of these resources.”

Of course, this boost the argument for hydraulic fracturing, or “fracking” the process used to extract the natural. Environmental groups have been on the warpath against it because the growing abundance of natural gas  – which is cleaner-burning than other fossil fuels —  threatens to undermine the case for renewable energy resources.

The administration is weighing new rules for fracking. It has given indications that it supports it in the past. Jewell’s comments about reducing dependence on foreign oil seem to be a another indication that they intend to push forward with allowing development of the resources.