The U.S. Geological Survey estimates that the Piceance Basin in western Colorado has about 50 percent more oil shale than thought 20 years ago.
The USGS said Thursday it revised its estimate to about 1.5 trillion barrels of in-place oil-shale resources after looking at new areas that previously had too little data for research.
The USGS study didn’t try to estimate how much oil might be recoverable.
The Department of Energy has used an estimate that the Green River Formation, which covers parts of Utah, Wyoming and Colorado, including the Piceance Basin, contains up to 1.8 trillion barrels of in-place resources, with about 800 billion barrels of recoverable oil.
Interior Secretary Ken Salazar released a statement saying the new estimate demonstrates the need for research and development.
The American Petroleum Institute agreed and said it was disappointed that Salazar in February scrapped plans to expand a program offering leases for oil-shale research and development.
