Arches National Park in Utah, in western part of the USA contains one of the largest concentrations of natural sandstone arches in the world. Other extraordinary geologic features, such as spires, pinnacles, pedestals and balanced rocks can also be found here.
The area lies atop an underground salt bed, which is basically responsible for the arches and other geological forms. This salt bed was deposited when the sea in this area evaporated millions years ago. Later, a rock formed a cover for salt layer. High pressure on the salt caused by heavy rock forced a salt to shift and reposition. This movement produced vertical cracks. Erosion - water and extreme temperatures - created the rest: arches, balanced rocks, sandstone fins and monoliths.
Cryptobiotic Soil Crust covers much of the desert. Composed of cyanobacteria as well as lichen, algae, fungi protects against erosion, absorbs moisten and serves as fertilizer. Without this crust many of the larger plants cannot survive. This is a very important element in this unusual place.
