The gypsum and shale buttes are relics of millions of years of geologic history. During the Permian Period about 250 million years ago, shallow seas covered all of western Oklahoma and the Texas Panhandle, depositing white gypsum and red-brown shale. Later, gypsum crystals and rock layers formed as calcium sulfate saturated water trapped in mud on the sea floor. Over time, both the shale and the gypsum were buried beneath several thousand feet of more recent sediments. About 65 million years ago, development of the Rocky Mountains caused the broad uplift of the western United States, raising Oklahoma and surrounding areas above sea level. Subsequent and ongoing erosion of the overlying sediments exposed the layers of shale and gypsum. In the Blaine Formation, a crown of white gypsum is approximately 10 feet thick. Flowerpot shale, the oldest formations cropping out in the western part of Major County, is red-brown shale with thin layers of white gypsum and dolomite with green-gray shale. Badlands soil consists of Permian redbeds of shale and clay tinted by iron oxide, the mineral hematite.