Name applied to a useful marker, a zone of limestone, "in the arkosic limestone member" [cannot divide a member into a member] of the Madera formation. Is typically developed at 13,000 ft elevation on north side of north fork of Whiskey Creek, Whiskey Creek Pass, Las Animas Co, CO on the Sierra Grande uplift. No type locality designated. Is about 150 ft thick. Consists of gray and green sandstone and shale interbedded with sandy oolitic limestone with pelecypods, bellerophontid gastropods, and near base, fusulinids. This same bed on Sangre de Cristo Creek west of La Veta Pass was called the gastropod bed. Is similar to Jacque Mountain limestone member of Minturn formation. This same limestone zone crops out on Coyote Creek southeast of Guadalupita and on the Mora River, Mora Co, NM in the Las Vegas-Raton basin. Fossils listed. Desmoinesian age. Cross section; identified at Veta Pass and Whiskey Creek Pass, CO and south to Pecos in NM. Lithofacies map.

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

Is the upper member of the Madera formation at La Veta Pass and Huerfano Park, Huerfano Co, CO in the Las Vegas-Raton basin. Underlies the newly named Pass Creek sandstone at La Veta Pass. Underlies Sangre de Cristo formation in Huerfano Park. Overlies arkosic limestone member of Madera. Identified at several localities between Pecos, NM and La Veta Pass, CO. Is an epineritic to littoral deposit. Assigned to the Desmoinesian or [Middle] Pennsylvanian. Correlation chart.

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