First use of the Mountain Springs Formation. Age is Late Ordovician, Silurian, and Early Devonian.
Source: GNU records (USGS DDS-6; Menlo GNULEX).
Unit is named the Mountain Springs Formation. Is divided into nine informal units. Consists of thin-bedded, gray dolomite. Thickness is 116 m at type. Disconformably overlies the Nopah Formation; underlies the Ironside Member of the Sultan Limestone. Age is Late Ordovician, Silurian, and Early Devonian based on fossils. (B1520)
Source: GNU records (USGS DDS-6; Menlo GNULEX).
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