Fantasy Canyon

Fantasy Canyon is a 10-acre site of unusual eroded rock formations about 27 miles south of Vernal, in Uintah County, Utah. It formed during the Eocene epoch, between 55 and 34 million years ago, at the edge of the vast subtropical Lake Uinta, which at its peak stretched from the Wasatch Plateau to western Colorado; rivers feeding the shrinking lake deposited sand, silt and clay shed from nearby mountains, which was later buried and solidified into layers of sandstone, mudstone and claystone. The canyon's pinnacles, pillars, arches and knobs are carved from a sandstone layer of ancient river-channel sediment, sandwiched between finer floodplain deposits of mudstone and claystone that erode into surrounding badland topography, the mudstone showing alternating gray, olive and reddish-purple stripes. Because the mudstone and claystone wear away faster than the more resistant sandstone, differential erosion has sculpted the sandstone into the canyon's bizarre, melted-wax-like shapes. This entity documents Fantasy Canyon specifically as a geological formation.