From the Railroad Commission of Texas website.....

From the Railroad Commission of Texas website..

http://www.rrc.state.tx.us/oil-gas/major-oil-gas-formations/permian-basin/

The Permian Basin remains a significant oil-producing area, producing more than 270 million barrels of oil in 2010 and more than 280 million barrels in 2011.  The Permian Basin has produced over 29 billion barrels of oil and 75 trillion cubic feet of gas and it is estimated by industry experts to contain recoverable oil and natural gas resources exceeding what has been produced over the last 90 years.  Recent increased use of enhanced-recovery practices in the Permian Basin has produced a substantial impact on U.S. oil production.