White Pocket, Arizona

White Pocket is a formation of Navajo Sandstone within Vermilion Cliffs National Monument in Arizona, on the Colorado Plateau, where most exposed sandstone in the area weathers to a reddish color but the rock at White Pocket is blanketed in a distinctive white surface layer. The white capped remnants form contorted, folded shapes nicknamed cauliflower rock, with cross bedding exposed at many different orientations across the landscape. Geologists have proposed several explanations for the unusual white crust, including soft sediment deformation, large scale slumping triggered by ancient earthquakes, and a more recent theory that a weathering crust built up from minerals carried by groundwater in an arid climate. No single explanation has been settled on, and White Pocket remains one of the more geologically debated formations on the Colorado Plateau.