Oil-sand and heavy-oil potential of Oklahoma

There are over 300 reported occurrences of heavy oil and bitumen-impregnated rocks in the State of Oklahoma. Surface oil seeps in the southern part of the State led to the discovery of some of the giant oil fields in that area. Historical records describing the mining activity in the Tri-State area of Kansas, Oklahoma, and Missouri indicate that heavy oil had to be removed daily from some mine shafts before the shafts could be worked. The Oklahoma Geological Survey, in cooperation with' the United States Department of Energy, has recently completed a resource appraisal of the heavy-oil potential of two counties in northeastern Oklahoma. The results of our study suggest that heavy-oil potential for the Oklahoma portion of the Tri-State area is not as great as previous estimates indicated. About 20 percent of the State's heavy-oil and oil-sand occurrences are in south-central Oklahoma, in Carter and Murray Counties. Bitumen-impregnated rocks in this area consist of Ordovician sandstones and limestones and Pennsylvanian sandstones. Many such outcrops have been quarried for local paving needs. Heavy oil occurs in shallow wells at 70 to 75 m (230 to 245 foot) depths and also in hand-dug water wells. We believe that oil sands and heavy oil in south-central Oklahoma could significantly increase the fossil-fuel resource base of the State.