NABSQNO 12S-686453-4334580

Rainbow Arch west of Grand Junction,
Colorado Photo by Jay Wilbur
Example Pothole Natural Arch
NABSQNO 12S-686453-4334580. Rainbow Arch is an old pothole natural arch eroded through Entrada sandstone. In this case, when the pothole reached and was laterally diverted by the more resistant Navajo sandstone beneath the Entrada, it almost immediately breached the cliff wall. Since the lintel is arched and the opening is semicircular, this arch is considered old.
Rainbow Arch is one of several arches found in the cliffs above the outer gorge of Rattlesnake Canyon. This area is managed as a wilderness by the BLM in Grand Junction, Colorado, and has been frequently considered for annexation by Colorado National Monument. This natural arch is listed in the Vreeland catalog as 18-16.
Other Pothole Natural Arch examples:
© 2003 by Jay H. Wilbur,
All Rights Reserved.
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