Unit is named the Tierra Redonda Formation. Consists of fine- to coarse-grained, thick-bedded, friable to well-cemented, white and yellowish-gray sandstone (calcareous in the lower part) and boulder conglomerate. Thickness is 1650 ft at type. Conformably overlies the Vaqueros Formation; conformably underlies the Sandholdt Member of the Monterey Shale. Age is early and middle Miocene. (B1520)
Source: GNU records (USGS DDS-6; Menlo GNULEX).
Age of the Tierra Redonda Formation is modified from early and middle Miocene to: middle Miocene based on fossils [mollusks].
Source: GNU records (USGS DDS-6; Menlo GNULEX).
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
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