Natural gas from shale formations such as North Texas' Barnett Shale comprised 23 percent of total U.S. production in 2010, according to the U.S. Department of Energy.
Shale gas output was 4.87 trillion cubic feet in 2010, the department's Energy Information Administration said in a release Tuesday, according to a Bloomberg News report.
That's an approximate 57 percent jump in shale gas production from the output of 3.11 trillion cubic feet in 2009.
In an assessment of 48 shale gas basins in 32 countries, the EIA said technically recoverable shale gas resources totaled 5,760 trillion cubic feet. Adding the U.S. estimate of 862 trillion cubic feet results in a total world shale resource base estimate of 6,622 trillion cubic feet.
That global number is enough gas to supply the U.S. for roughly 250 to 300 years at current consumption rates, according to Star-Telegram calculations.
--Jack Z. Smith