USGS releases assessment of undiscovered oil and gas resources in Texas’ Maverick Basin

11 trillion cubic feet of gas and 366 million barrels of oil estimated in the Western Gulf Basin Province.

RESTON, Va. — The U.S. Geological Survey released its assessment of potential for undiscovered oil and gas in formations of the Maverick Basin, assessing that there are technically recoverable resources of 366 million barrels of oil and 11 trillion cubic feet of gas.

Since exploration began in the area in the 1930s, the Maverick Basin has produced at least 306 million barrels of oil and 3.4 trillion cubic feet of gas. Today’s finding of 11 trillion cubic feet of gas is as much gas as the United States consumes in four months at the current rate of consumption and is more than three times the total historic gas production.

“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, our assessment found substantial undiscovered natural gas resources,” said Sarah Ryker, acting director of the USGS.

The assessment area includes the Maverick Basin and adjacent areas in southwestern Texas (see map).  The USGS looked at a total of 9 assessment units in the basin, including both conventional and continuous reservoirs of oil and gas in the Escondido, Olmos, and San Miguel formations of the southwestern Texas coastal plain.

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 policy makers 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 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 Maverick Basin Oil and Gas Assessment is available https://doi.org/10.3133/fs20253015.

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