USGS releases assessment of undiscovered oil and gas resources in the Phosphoria Total Petroleum System of SW Wyoming and NW Colorado

Since production began around 1920, the Phosphoria system has yielded approximately 500 million barrels of oil and 2.5 trillion cubic feet of natural gas.  The new assessment estimates undiscovered, technically recoverable resources to a depth of 15,000 feet. 

This is the third oil and gas assessment in the Southwestern Wyoming Geologic Province released this year, following the assessments of the  Mowry Composite Total Petroleum System, which lies below the Niobrara Formation. The geologic province continues to produce abundant oil and gas from other formations, such as the Lance Formation, Lewis Shale, and the Mesaverde Group, none of which are accounted for in this assessment.   

“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 that 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. 

USGS oil and gas assessments began 50 years ago following an oil embargo against the U.S. that signaled a need to understand the occurrence, distribution and potential volumes of undiscovered resources.  The embargo led to a mandate for the USGS to use geologic science and data to assess undiscovered oil and gas resources to help meet the nation’s needs.  The work continues today – identifying new resources for domestic production as well as international resources that affect market conditions — an important part of the USGS mission to provide actionable insight to U.S. leaders, other Federal agencies, industry and the public. 

USGS energy resource assessments provide information to policymakers on resource potential in areas of the U.S. and the world. For land-management agencies such as the Bureau of Land Management, the results of an energy resources assessment feed into land-use and resource management plans.  For the private sector, USGS assessments of undiscovered energy resources provide context for planning detailed exploration. 

The range of assessments produced has changed with the technology available to produce oil.  In 1995, the USGS began conducting assessments of unconventional, technically recoverable resources.   

The USGS Energy Resources Program assesses the potential for undiscovered oil and gas resources in priority geologic provinces in the United States and around the world. Two methodologies are used by the USGS: one for assessing conventional oil and gas resources and one for assessing unconventional (continuous) oil and gas resources (such as shale gas and coalbed gas).   

The fact sheet on the Phosphoria Total Petroleum System Oil and Gas Assessment is available HERE