Image: Devils Tower aerial

Description: Devils Tower, a national monument in northeastern Wyoming, above the Belle Fourche River. Familiar to most folks as the setting for Close Encounters of the Third Kind, it was known by the Sioux as "Mato Tipila, which means “Bear Lodge”. In fact it is the neck of a long-extinct volcano. The circular shape of the land around it suggests the shape of the volcano itself. While Devils Tower is Tertriary in age (40-some million years old), the rock through which it intruded is a good bit older. The red rock is the Permian-Triassic Spearfish Formation, about a quarter-billion years old. Above it the white layer is of the more recent (Jurassic) Gypsum Spring Formation, which interests me mostly because, like so many other formations in Wyoming, it was named by J. David Love, the great Rocky Mountain Geologist who was the primary human subject of John McPhee's books Rising from the Plains, and Annals of the Former World.
Title: Devils Tower aerial
Credit: 2010_11_06_sfo-bos_312 Uploaded by PDTillman
Author: Doc Searls from Santa Barbara, USA
Usage Terms: Creative Commons Attribution 2.0
License: CC BY 2.0
License Link: http://creativecommons.org/licenses/by/2.0
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