Named for exposures on both sides of Engelmann Canyon, T10S, R11W, northeastern Dugway Range, Tooele Co, UT in the Great Basin province where the entire formation is present. Contacts usually covered by alluvium. Partial section measured on Spor Mountain where rocks were previously assigned to the Simonson and Guilmette formations. Also occurs in low hills on west side Dugway Range in several low hills 2 mi south-southeast of Cannon Canyon, and in a band 1.8 mi long extending north from Goshoot Canyon, Juab Co, Black Rock Hills. No type locality designated. Consists of massive sandy-textured, light-gray to black dolomite with some light-gray to black limestone in lower half. May be as much as 2,750 ft thick. Is younger than Sevy dolomite and older than Goshoot formation (new). Fossiliferous (brachiopods, gastropods, conodonts, corals). Is equivalent to Sevy and Simonson dolomites, most of Guilmette formation, West Range limestone, and Bluebell dolomite. Of probable Middle Devonian (lower) and Late Devonian (upper) age. Geologic map.

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