In the southeast region of The geologists are a little puzzled over exactly how many of the arches were formed. One key may be salt. At one time, it is suspected that this area was covered by an ancient salty sea. Below the sandstone surface are huge salt deposits, thousands of feet thick in some places, which were formed as the sea evaporated. Once dry, debris from erosion of surrounding lands accumulated in the valley of the former sea. Add lots of time and more erosion debris, and you eventually get sandstone. The problem is that salt is not inherently stable building material. So when the opportunity presented itself, the salt, mixed with a little groundwater, flowed from on spot to another like when you squeeze a tube of toothpaste. The rock above fell in some areas and rose in others. This shifting ground is suspected to have provided cracks in the sandstone that accelerated the erosion process. Sometimes there were stress concentrations that fractured the rock below the surface. These weakened locations eroded away, leaving intact a stone bridge or arch. At least, that’s the theory. Relatively close to the entrance to the park is a formation known as the Three Gossips. At the time we got to the park, the sun was near the “heads” of the Gossips. Flat The Delicate Arch is probably the park’s most famous arch. In fact, this arch is on the Much of the surface of the ground here is covered with a bumpy, dark brown crust known as cryptobiotic soil crust. The cryptobiotic skin is made up of cyanobacteria, mosses, soil lichens, green algae, microfungi, and bacteria. This skin helps make it possible for other plants to live in the desert by depositing nitrogen from the air into the soil, providing a safe haven for seeds, and providing resistance to the forces of water and wind erosion. |
The Three Kings/Three Gossips
Delicate Arch
Valley View
Landscape Arch
Valley View
Balanced Rock
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