A recent assessment discovered millions of barrels of oil and billions of cubic feet of natural gas resources in northwest Colorado and southwest Wyoming.

The United States Geological Survey announced the discovery of new resources in the Phosphoria Total Petroleum System, which has been producing oil and gas since approximately 1920. Since then, approximately 500 million barrels of oil and 2.5 trillion cubic feet of natural gas have been recovered from the system.

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Map of Phosphoria oil and gas assessment

United States Geological Survey

The new discovery includes an estimated 3 million barrels of oil and 666 billion cubic feet of gas that are recoverable. Despite the survey’s findings, the USGS believes that the system may be nearing depletion.

“USGS energy assessments typically focus on undiscovered resources – areas where science tells us there may be a resource that industry hasn’t discovered yet. In this case, after 100 years of production, we estimate the Phosphoria Total Petroleum System has relatively little remaining oil and more than 600 billion cubic feet of gas,” said Sarah Ryker, acting director of the USGS.

Other formations across the province, including the Lance Formation, Lewis Shale and the Mesaverde Group, continue to produce abundant oil and gas, the USGS said.

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