The Wildcat Peak Formation is exposed only in the northern part of the Toquima Range, Nye County, Nevada. It lies on western siliceous assemblage rocks (Ordovician Vinini Formation) and eastern carbonate assemblage rocks (Ordovician Pogonip Group and Silurian Roberts Mountains Formation), which were juxtaposed by thrusting during the Antler orogeny. The Wildcat Peak consists of three datable marine tongues separated by intervals of coarse clastic deposits. The coarse clastic intervals resulted from truncation following sporadic and cyclic uplifting that continued after the emplacement of the Roberts Mountains allochthon.

In the literature, age assignments for the formation range from Early Pennsylvanian (Atokan) to Early Permian (Wolfcampian). These age assignments are correct, but they only represent the middle and upper parts of the formation. Microfossil analysis has now established that the lower part of the Wildcat Peak is mid-Mississippian (Meramec). All microfossil dates are from material collected from transgressive limestones.

The new information indicates that major Antler thrusting ceased prior to mid-Mississippian time in the Toquima Range. This restricts the length of time of the Antler orogeny from Late Devonian to pre-middle Mississippian (Meramec) instead of Late Devonian to mid-Pennsylvanian. Such an interpretation is consistent with recently published data from the Pinyon Range area, Nevada.

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