Our Beautiful Planet

Grand Canyon album

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Angels Window at North Rim Grand Canyon (Arizona USA) along the road to Cape Royale. You can see the Colorado River through it. During the uplift of the Kaibab Plateau about 70 million years ago, stress and strain caused the rock to fracture forming vertical joints that intersect the horizontal bedding planes. Weathering (rain, freezing and thawing) along these planes and joints has eroded a hole in the Kaibab limestone and enlarged it to form the window. (Information taken from the roadside sign.)

Photograph taken June 2008. This image is 42% size of the original. The previous picture shows it in context.

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Grand Canyon album

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last updated: August 31, 2008