The Great Unconformity. Beds of Cambrian Coronado Quartzite overlie massive Proterozoic granite in the Morenci area, southeastern Arizona. (Photo by Charles Ferguson). For more on the geology of the Morenci area, see Charles' "Digital geologic map and cross sections of the Clifton-Morenci area, Greenlee County, Arizona, v. 1.0" at http://repository.azgs.az.gov/uri_gin/azgs/dlio/461 .
Photographer: Charles Ferguson
Photo Date: circa 2011