Did they count oil shale deposits?
Oil shale is at present a “resource” not a “reserve” since it is not known how or if the stuff can be processed to produce oil on an economically viable basis. [One of the Baltic States has produced oil shales for energy from a particularly rich deposit. It is my understanding that in that instance the kerogen was not processed to make oil, the rock itself was in essence thrown in a furnace. If that is the case, the result would something like burning the worst grade of coal imaginable.]