#devils garden

Devils Garden, Arches National Park (No. 3)

The Devils Garden Trail meanders between sheer walls of sandstone fins. The fins were created when vertical cracks in a thick layer of sandstone were eroded and widened by water—either scoured by runoff from rainfall and snow melt, or pried and exfoliated by ice expansion. These stone formations may only last a few thousand years—a short time on the geologic time scale. The events that led to the arches, fins, and other rock shapes began about 300 million years ago, when seas periodically covered the area. The seas became trapped in low-lying areas and then evaporated, leaving salt beds up to 5,000 ft (1,524 m) thick in some places. Sand, silt and clay subsequently accumulated on top of the salt deposits over millions of years. The uneven weight and pressure of these overlying sediments squeezed the salt into an anticline (a domed ridge). Overlying horizontal rock layers bulged upward and cracked vertically allowing rainwater to trickle down and dissolve the salt away.

As the salt receded, the overlying rock burden sank with it. Salt Valley, located to the immediate southwest, is an example of the resulting landform. At the edges of the valley, where Devils Garden is located, the cracked rock was slightly pulled apart. Rain and snow soaked into the vertical cracks, which dissolved the cementing minerals and loosened grains of sand to be carried away by running water. As the cracks widened, tall fins were left standing. Weak zones in fins were either dissolved by naturally occurring acids in rainwater or wedged apart by freezing and thawing water, and openings developed into the various arches seen presently.

THE WATCHER – Photography by Edgar Erglis

Full moon rising over the Devils Garden at Escalante area, Bryce Canyon, Utah.