How Arches Are Formed
In the Windows area, you can see many stages of arch formation. Look closely. Some arches are hard to see because of rock walls behind them.
Entrada Sandstone — the rocks in which arches are formed — was deposited here as sand more than 150 million years ago. Over time it was buried by new layers, hardened into rock, and shaped by the powerful forces of erosion.
1 A series of uplifts and collapses caused severe cracking in the 300-foot (91-meter) layer of buried Entrada Sandstone.
2 When overlaying rock layers eroded away, the Entrada was exposed to weathering. Cracks slowly widened and parallel rock walls, called fins, were formed.
3 Rainwater continually dissolves the natural cement that holds sandstone together. This process combines with the pressure from water freezing in tiny cracks and causes the sandstone to flake and crumble. Eventually, enough rock falls out of a fin that an opening is formed.
4 These holes continue to erode, and in time, the same forces of weathering that created arches will destroy them.
Nature's Sculptured Landscape
[Left photo] Turret Arch
[Right photo] South Window - North Window
Erected by National Park Service.
Topics. This historical
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Location. 38° 41.22′ N, 109° 32.189′ W. Marker is in Arches National Park, Utah, in Grand County. Marker is at The Windows Trailhead, just beyond the parking lot along the trail. Touch for map. Marker is in this post office area: Moab UT 84532, United States of America. Touch for directions.
Other nearby markers. At least 8 other markers are within 7 miles of this marker, measured as the crow flies. Double Arch (about 800 feet away, measured in a direct line); Balanced Rock (approx. 1.9 miles away); Ancient Sand Dunes (approx. 3.1 miles away); Wolfe Ranch (approx. 3˝ miles away); Utah Serviceberry (approx. 6.7 miles away); Harriman's Yucca (approx. 6.7 miles away); Rubber Rabbitbrush (approx. 6.7 miles away); Grand Old Ranch House (approx. 6.7 miles away). Touch for a list and map of all markers in Arches National Park.
Also see . . .
1. Arches National Park. (Submitted on November 13, 2020, by William Fischer, Jr. of Scranton, Pennsylvania.)
2. The Geologic Story of Arches National Park. (Submitted on November 13, 2020, by William Fischer, Jr. of Scranton, Pennsylvania.)
Credits. This page was last revised on November 25, 2020. It was originally submitted on November 13, 2020, by William Fischer, Jr. of Scranton, Pennsylvania. This page has been viewed 370 times since then and 66 times this year. Last updated on November 14, 2020, by Craig Baker of Sylmar, California. Photos: 1, 2, 3. submitted on November 13, 2020, by William Fischer, Jr. of Scranton, Pennsylvania. • J. Makali Bruton was the editor who published this page.
