Named for Whitmore Wash [not precisely located] as the basal member of Redwall Limestone. Type section is about 1/4 mi north of Colorado River, northern AZ in the Plateau sedimentary province. Is largely dolomite in southeast sections, and limestone with well-rounded bioclasts, and locally of ooids to the west. Has medium scale crossbeds. Ranges from 72 to 85 ft thick. Unconformably overlies Temple Butte Limestone; underlies Thunder Springs Member. Is of Mississippian age.

Source: GNU records (USGS DDS-6; Denver GNULEX).

The name Redwall Limestone of Early and Late Mississippian age is extended northward from AZ into Kane Co, UT in the Plateau sedimentary province. Redwall unconformably overlies the Upper Devonian and Lower Mississippian Ouray? Limestone and unconformably underlies the Lower Pennsylvanian Molas Formation. The formation is divided in three parts (ascending): 1) Whitmore Wash and Thunder Springs Members, 232 ft thick; 2) Mooney Falls Member, 289 ft thick; and 3) Horseshoe Mesa Member, 160 ft thick. The Whitmore Wash and Thunder Springs are white, fossiliferous dolomite with white tripolitic chert. The Mooney Falls is a white to brown, crinoidal, cherty dolomite with a few thin brown limestone beds. The Horseshoe Mesa is a brown to white limestone with chert, and algal structures. The Early-Late Mississippian boundary lies within Mooney Falls Member. A marine deposit.

Source: GNU records (USGS DDS-6; Denver GNULEX).