The Great Unconformity exposed in Grand Canyon separates the Tapeats Sandstone from ancient Proterozoic rocks. The Great Unconformity represents ~1.2 billion years of missing rock record, either due to erosion or non-deposition.
Photo Date: circa 2000
Photo Location Accuracy: Approximately Located
Photo Tags: Grand Canyon, Tapeats Sandstone, Great Unconformity, Proterozoic, Cambrian, Paleozoic 
