Johns Wash limestone is named for exposures at the head of Johns Wash (type section: Wheeler Peak 15' quad, White Pine Co, NV). Has been recognized on high peaks 3 mi east of Lincoln Peak, and above Corset Spring. Overall unit is light to dark gray limestone. Base of unit is marked by limestone-pebble conglomerate; overlain by limestone with beds about 1 in thick that are grossly cross-bedded; overlain by wavy-bedded and platy limestone containing calcite blebs and veinlets; overlain by a clastic and crystalline unit mottled with specks of iron oxide; overlain by a coarsely crystalline and bioclastic unit. Thickness at type is 250 ft. Overlies Lincoln Peak formation (new); underlies Corset Spring shale (new). Age is early or middle Late Cambrian on the basis of fossils.

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

Johns Wash Limestone is reduced in rank to the Johns Wash Limestone Member [middle of five] of the Orr Formation in the Confusion Range [Conger Mountain 15' quad], Millard Co, UT. Thickness is about 150 ft. Overlies (informally named) Shale Member of Candland [Candland Shale Member; Hintze, 1973); underlies Corset Spring Shale Member (reduced in rank). Age is Cambrian.

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

Reduced in stratigraphic rank from Johns Wash Limestone to a member of Orr Formation in the House Range of the Great Basin province, western UT, where it is a ledge- and cliff-forming unit between the Candland Shale Member (new) below, and the Corset Spring Shale Member (reduced in stratigraphic rank) above. The lower half is dark-gray oolitic limestone, and the upper half is a lighter gray, massive limestone. Is between 26 m (Cricket Mountains) and 76 m (type section); 41 to 80 m in House Range. Measured section [Orr Formation type] in sec.33, T18S R13W, Notch Peak 15' quad, Millard Co. Is assigned to the Late Cambrian on the basis of fossils (trilobites) and stratigraphic position. Is absent in the Wah Wah Mountains and south end of the House Range, UT. In southern Snake Range, NV, Johns Wash is of formation rank. Correlates with: Hicks Formation of Deep Creek Range, UT; Straight Canyon Formation of Dugway Range, UT; and Opex Formation of East Tintic Mountains, UT.

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

Johns Wash Limestone Member of the Orr Formation may be subdivided into five facies: 1) a bioclastic facies of thin-bedded fossiliferous or mottled wackestones, 2) an oolitic facies of cross-bedded oolitic intraclastic grainstones, 3) a stromatolitic facies consisting of diverse types of algal stromatolites in an oolitic matrix, 4) a pelletoidal facies of burrowed, light gray, oolitic grainstones and pelletoidal packstones, and 5) a fenestral facies of extensively burrowed and bored, light gray mudstones and packstones which possess fenestral fabric. Age is Late Cambrian (Dresbachian and Franconian).

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