Intelligence brief: Colorado shale is almost size of Marcellus; Pipeline bill calls for new technologies Jun 14, 2016 Colorado is famous for its high peaks; now it could also be known for its shale Colorado sits on 40 times more natural gas than previously thought, according to an updated estimate by the US Geological Survey.The USGS said the Mancos Shale in the Piceance Basin contains about 66 trillion cubic feet of undiscovered, technically recoverable shale natural gas, 74 million barrels of shale oil and 45 million barrels of natural-gas liquids, according to the estimate, the first since 2003.More than 2,000...