Fig. 15

The Temple Butte Formation is predominantly dolomite or sandy dolomite in lithology, with minor sandstone and limestone beds. Although marine fossils are relatively abundant, few identifiable organic remains have been found. Those that have were reported as intermediate brachiopods, gastropods, corals, and "placoganoid" fish. Rare silicified corals, gastropods, crinoid plates, and massive stromatoporoids have also been reported. This formation records minor depositions of a thin carbonate sequnce that gradually thickens westward across the Grand Canyon region. The easternmost outcrops and some of the basal strata to the west probably were deposited in narrow tidal channels under intertidal conditions. The more laterally extensive dolomite beds in the central and western portions of the Grand Canyon accumulated in more subtidal but probably very shallow-marine conditions across a gently submerged continental shelf.