Where is it found?

The largest deposit of oil shale in the world is located in the Piceance Basin of western Colorado. The USGS estimates this resource at about 1.5 trillion barrels of oil. Before it can be used, someone has to figure out how to commercially convert the kerogen in that deposit into crude oil. For that to occur, oil prices have to be sufficiently high to make it economically viable. Estonia has been producing oil from oil shale for decades. Other efforts to commercially produce it are ongoing in China and Jordan.