Pg. 99 (table 2), 110-111, pl. 1. Asphalt Ridge sandstone of Mesaverde group. Defined as lower of two basal marine sandstones of Mesaverde group in Vernal (northeastern Utah) region. Usually a single massive yellow to white soft sandstone bed bounded on top by a thin tongue of Mancos shale and on bottom by main body of Mancos shale. Upper boundary transitional; in some places it is impossible to draw a sharp line between Asphalt Ridge and overlying Rim Rock sandstone (new). Thickness about 100 feet. Fossiliferous (mollusks). Age is Late Cretaceous (post-Niobrara).
Typically exposed in Asphalt Ridge, [in T. 4 and 5 S., R. 21 E., Vernal NE and Vernal SE 7.5-min quadrangles, Uintah Co.], northeastern UT. Traced, with interruptions, from north end of Asphalt Ridge to the Rim Rock at Green River, where it feathers out into main body of Mancos shale. [Not separately mapped.]

Source: US geologic names lexicon (USGS Bull. 1200, p. 155-156); supplemental information from GNU records (USGS DDS-6; Denver GNULEX).