Arches National Park is located in East Central Utah, near the town of Moab, UT. Most of the exposed rock in the park are salmon colored Entrada Sandstone (where most of the arches form) and lighter colored Navajo Sandstone. Over time, water and ice forms in the fissures between the two layers As the water freezes, it expands, chipping bits of rock away. As this rock falls or is blown away, a hole forms. Eventually, larger chunks start falling off and you get an arch. The weathering never stops, and after a long time, these arches will collapse, even as new ones are formed.
I was at Arches several days, so I have a lot of good photos. Too many to put on one page, so I have split them out.
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