RESTON, Va., Dec. 18 (UPI) -- The U.S. Geological Survey said its review of the Barnett shale basin in north-central Texas led it to double the estimated reserve potential.
"We decided to reassess the Barnett Shale following the successful introduction of horizontal drilling and hydraulic fracturing, setting the stage for the current shale gas boom," USGS researcher Kristen Marra said in a statement.
The USGS estimates the shale basin holds 53 trillion cubic feet of shale natural gas, 172 million barrels of shale oil and 176 million barrels of natural gas liquids. The estimate, which is double the previous level forecast in 2003, is for undiscovered, technically recoverable resources.
The USGS said the increase in reserve potential was largely a reflection of the industry's use of horizontal drilling, where the well turns at depth to parallel the source, in coordination with hydraulic fracturing. The previous assessment relied on vertical drilling. Since 2003, more than 16,000 horizontal wells were tapped into the Barnett shale, the report said.
The Texas Railroad Commission, the state energy regulator, estimates the Barnett shale may be one of the more lucrative natural gas basins in the country. The Marcellus shale in the eastern United States overtook Barnett, however, as the larger producer earlier this decade.
Referencing field data, the (Fort Worth) Star-Telegram reported the number of rigs deployed in the Barnett shale went from 200 in October 2008 to just a single rig at one point in early 2015.
Lower crude oil prices are starving energy companies of the capital needed to invest in exploration and production, a trend reflected in declining rig counts. June data from the U.S. Energy Information Administration suggests Barnett shale peaked earlier this decade, but may recover somewhat by 2020 before leveling off through 2050.