The U.S. Geological Survey (USGS) quantitatively assessed the potential for undiscovered, technically recoverable continuous oil and gas resources in the Eastern Great Basin Province of Nevada, Utah, and Idaho.
The major petroleum source rocks are the Upper Devonian– Lower Mississippian Pilot Shale and the Mississippian Chainman Formation. The geologic model applied to the Pilot Shale and shales in the Chainman Formation is for these shales to have achieved generative maturity for oil by burial to at least 8,700 feet (2,652 meters) within some of the Neogene extensional.
Areas that satisfy this depth requirement were defined using modeled gravity data that were calibrated to the petroleum system in Railroad Valley and Pine Valley in Nevada.
The estimated means for undiscovered resources are 534 million barrels of oil (MMBO) with an F95 to F5 range from 0 to 1,344 MMBO, 156 billion cubic feet of gas (BCFG) with an F95 to F5 range from 0 to 414 BCFG, and 2 million barrels of natural gas liquids (MMBNGL) with an F95 to F5 range from 0 to 6 MMBNGL.
For oil and gas accumulations, zeros at F95 reflect the interpretation of geologic risk (AU probability less than 1.0) on the potential occurrence of one well of minimum EUR in the AU. Of the mean total shale-oil resources of 534 MMBO, 246 MMBO, or 46 percent, is in the Pilot Shale Oil AU, and 288 MMBO, or 54 percent, is in the Chainman Shale Oil AU.