[?] Boucher Tongue of Muav Limestone of Tonto Group (AZ-local)
[?] Boucher Tongue of Bright Angel Shale of Tonto Group (AZ-local)
Recognized locally in Grand Canyon.
Middle Cambrian
Notable exposures from vicinity of Garnet Canyon southeastward to Cottonwood Canyon, a distance of 25 mi, Grand Canyon area [Coconino Co., northwestern AZ] (McKee, 1945).
Plateau sedimentary province
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
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