USGS notes ‘significant’ undiscovered resources in Woodford, Barnett shales in Permian basin

Advances in unconventional production now make it possible to produce energy resources from previously inaccessible and technically challenging formations.

Jan. 14, 2026

2 min read

Woodford shale, Barnett shale, Permian basin — Maps showing the locations of (A) four continuous and one conventional assessment units (AUs) in the Woodford shale and (B) four continuous AUs in the Barnett shale of the Permian basin province.

The Woodford and Barnett shales in the Permian basin contain technically recoverable resources of 28.3 tcf of gas and 1.6 billion bbl of oil in New Mexico and Texas, according to the US Geological Survey (USGS).

The gas volumes are enough to supply the United States for 10 months at the current rate of consumption, while the oil volumes account for 10 weeks’ supply for the nation, the USGS said in its Jan. 14 assessment release of undiscovered gas and oil in the Woodford and Barnett shales in the Permian basin.

Since production began in the late 1990s, the Woodford and Barnett shales have produced 26 million bbl of oil, equal to one day’s US consumption, USGS said.

The shales of the Woodford and Barnett occur up to 20,000 ft below the surface, at greater depths than other resources in the Permian, USGS said in the release, noting “advances in unconventional production – hydraulic fracturing and horizontal drilling – now make it possible to produce energy resources from previously inaccessible and technically challenging formations, such as the Woodford and Barnett.”

“The US economy and our way of life depend on energy, and USGS oil and gas assessments point to resources that industry hasn’t discovered yet. In this case, we have assessed there are significant undiscovered resources in the Woodford and Barnett shales in the Permian Basin,” said Ned Mamula, USGS director.