The Colorado Plateau of Arizona, Colorado, New Mexico, and Utah is made of mostly flat-lying layers of sedimentary rock that record climate extremes ranging from oceans to widespread deserts over the last 1.8 billion years. Navajo Mountain in southeastern Utah is a dome-shaped chunk of igneous rock that intruded into the sedimentary layers and lifted up the overlying layer. Navajo Mountain is one of several of these rock formations, called laccoliths by geologists, in southeastern Utah’s portion of the Plateau. The region has special cultural significance to the Navajo people, who know it as Earth Head. Together with Rainbow Bridge to the northwest, Navajo Mountain figures prominently as the first settlement area in western Navajo origin stories.Image Credit: NASA