Upper Permian Stratigraphy of West Texas Permian Basin

By comparing the Upper Permian stratigraphy of West Texas and Oklahoma it is found that the Whitehorse of Oklahoma is equivalent to the lower evaporites of the southern basin and that the Permian of the Oklahoma Quartermaster is equivalent to the Yates sand. Formations above the Yates in the southern basin are younger than any of the Oklahoma or Kansas Permian.