One minute it was there, the next it was gone.
The collapse of "Wall Arch" at Arches National Park proves once again that gravity does work, even though you might wonder after gazing at the "rockitecture" of this dazzling Utah park.
Wall Arch, long a key attraction along the park's Devils Garden Trail, collapsed sometime overnight August 4. And since rock has continued to peel off of the collapsed arch, officials have been forced to temporarily close the popular trail just beyond Landscape Arch.
On Thursday representatives from both the National Park Service Geologic Resources Division and the Utah Geological Survey visited the site and noted obvious stress fractures in the remaining formation. Rock debris has completely blocked this section of the trail. The closure will remain in effect until visitor safety issues can be resolved.
First reported and named by Lewis T. McKinney in 1948, Wall Arch was a free-standing arch in the Slickrock member of the Entrada sandstone. The opening beneath the span was 71-feet wide and 33-1/2 feet high. It ranked 12th in size among the over 2,000 known arches in the park.
All arches are but temporary features and all will eventually succumb to the forces of gravity and erosion. While the geologic forces that created the arches are still very much underway, in human terms it’s rare to observe such dramatic changes.
No one has reported observing the arch collapse and there were no visitor injuries.