The US Geological Survey has determined that a vast shale field in West Texas could yield 20 billion barrels of oil, making it the largest source of shale oil the agency has ever assessed.

The agency said in a release Tuesday that the Wolfcamp Shale geologic formation in the Midland area also contains an estimated 16 trillion cubic feet of natural gas.

Click here for more on this new oil discovery in the Lone Star State.
Photo: Odessa American