Devils Garden Trail - Double O Arch
Arches National Park is a US National Park in eastern Utah. The park is adjacent to the Colorado River, 4 miles (6 km) north of Moab, Utah. It is home to over 2,000 natural sandstone arches, including the world-famous Delicate Arch, in addition to a variety of unique geological resources and formations. It contains the highest density of natural arches in the world.
The park consists of 76,679 acres (119.811 sq mi; 31,031 ha; 310.31 km2) of high desert located in the Colorado Plateau. Its highest elevation is 5,653 feet (1,723 m) at Elephant Butte, and its lowest elevation is 4,085 feet (1,245 m) at the visitor center. Forty-three arches are known to have collapsed since 1977. The park receives on average 10 inches (250 mm) of rain a year.
Administered by the National Park Service, the area was originally named a National Monument on April 12, 1929. It was redesignated as a National Park on November 12, 1971.
(Wikipedia)
Devils Garden is an area of Arches National Park, located near Moab, Utah, United States, that features a series of rock fins and arches formed by erosion. The Devils Garden Trail, including more primitive sections and spurs, meanders through the area for 7.2 mi (11.6 km). The trailhead leads directly to Landscape Arch after a 0.8 mi (1.3 km) outbound hike, while Tunnel Arch and Pine Tree Arch can be seen on spur trails on the way to Landscape Arch. Several other arches, including Partition, Navajo, Double O, and Private Arch, as well as the Dark Angel monolith and Fin Canyon, are accessed via the primitive loop trail and its spurs.
Wall Arch, before its collapse in 2008, was also located in Devils Garden just north of Landscape Arch. Black Arch is visible as a dark outline from the primitive trail and can be approached via an unmarked sidetrack.
The trailhead for Devils Garden is located at the end of the main park road. A campground and amphitheater are also available at the site.
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.
Landscape Arch, one of the world’s longest natural arches, spans about 290 ft (88.4 m) according to laser rangefinder measurements made in 2004, yet is only about 6 ft (1.8 m) thick near its center. The arch was almost 11 ft (3.4 m) thick until September 1991 when a few small pieces began to fall. Within seconds, a 60 ft (18.3 m) long by about 5 ft (1.5 m) thick slab of rock dropped from the underside of the thinnest section. Some of the large boulders on the slope beneath the arch are remnants of this event.
(Wikipedia)
Der Arches-Nationalpark ist ein Nationalpark der Vereinigten Staaten im Norden des Colorado-Plateaus am Colorado River nördlich der Stadt Moab im US-Bundesstaat Utah. Er bewahrt die weltweit größte Konzentration an natürlichen Steinbögen (engl.: arches), die durch Erosion und Verwitterung ständig neu entstehen und wieder vergehen. Im Parkgebiet sind über 2000 Arches mit einer Öffnung von mindestens 90 cm (3 Fuß) nachgewiesen. Die Ökosysteme des über 300 km² großen Parks reichen vom Flussufer des Colorado Rivers bis zum nackten Fels und sind durch die durchschnittliche Höhe von rund 1500 m über dem Meer bei Wüstenklima geprägt.
Das Gebiet wurde 1929 als National Monument unter Schutz gestellt und 1971 zum Nationalpark aufgewertet. Es wird vom National Park Service betreut.
(Wikipedia)
