Phyllitic shale over 100 ft thick is correlated with Mayflower at Manhattan 12 mi south of study area which is in Nye Co, NV, Great Basin province. Mapped undivided as Paleozoic sedimentary rocks. At Manhattan Mayflower assigned Ordovician? age by Ferguson (1921, U.S.G.S. Bull. 725-I). From regional work, F. G. Poole (oral commun., 1973) believes Mayflower in Manhattan district may be Cambrian in age and overlying Zanzibar Limestone is mostly if not all, Ordovician in age. Overlying and underlying rocks are correlated with Zanzibar and Gold Hill Formation, respectively, at Manhattan.

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

Mapped on south side of Jefferson Canyon in northeast part of quad, at west edge of Cretaceous granite of Round Mountain pluton about 5 km south of Round Mountain, and between Round Mountain and Belmont plutons in southeast part of quad. Consists of knotted schist with minor interlayered quartzite and silicified limy siltstone. Thickness probably several hundred meters though original upper and lower contacts not exposed. Underlies unnamed Middle Cambrian? limestone unit; stratigraphically overlies Gold Hill Formation, though Gold Hill forms thrust plate that overlies Mayflower. Chemical analyses. Considered here to be Cambrian(?) age on basis of lithologic similarity to several regional Cambrian shale units in eastern and southern NV.

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