MIDLAND, Texas (AP) - The U.S. 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.
Officials say the discovery is nearly three times larger than the shale oil found in 2013 in the Bakken and Three Forks formations in the Dakotas and Montana.
Because the oil is trapped in shale, more advanced drilling, such as hydraulic fracturing, would be needed to extract it.
The shale is within the Permian Basin, one of the most productive regions for oil and gas in the U.S.