Unit is named the Terra Cotta Mountains Sandstone for the Terra Cotta Mountains located in the southeastern part of the McGrath 1:250,000 quad, AK. Consists mainly of sandstone and mudstone with subordinate limestone. Apparently conformable on the Post River Formation (new); upper contact of unit is thought to be a bedding-plane thrust fault. Thickness is 185 m. Age is late Early and Late Silurian based on fossils (graptolites).
Source: GNU records (USGS DDS-6; Menlo GNULEX).
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
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