All photos courtesy of U.S. Geological Survey
Hoodoos, a pinnacle-shaped rock formation in the Devils Garden, Escalante Canyons, Grand Staircase-Escalante National Monument
Grand Canyon, Grand Canyon National Park
Snaggletooth Ridge, North Cascades National Park
Polygonal jointing and weathering in upper Navajo Sandstone, Grand Staircase-Escalante National Monument
Providence Mountains east of Kelso, Mojave National Preserve
