This view of the mouth of Mosaic canyon shows contrasting rock types exposed in the lower canyon. On the lower left are yellowish- or buff-colored, massive- to well-bedded Noonday Dolomite of late PreCambrian age (about 600 million years). The cliff on the right is an exposure of tightly-cemented conglomerate that formed probably with the past few hundred thousand years. Deposits like these suggest that the canyon has back-filled with alluvial sediments, possibly on several occasions.