About 1.45 trillion bbl of shale oil is estimated to be in place in the Eocene Green River formation in the Green River and Washakie basins in southwestern Wyoming, the US Geological Survey said.
The shale oil resource is present in the Tipton shale member, Wilkins Peak member, and LaClede bed of the Laney member of the Green River formation.
About 133 billion bbl of the resource is in strata that contain more than 15 gal/ton of rock, of which 72 billion bbl are under federal mineral ownership, USGS said.