The Intrenchment Creek Quartzite of Atlanta Group is here named in the Newnan-Tucker synform near Atlanta, GA. It consists of a thin unit of spessartine quartzite and spessartine mica schist. Manganiferous garnets cause the rock to weather to hard black quartzite, called coticule rocks and gondite elsewhere. Unit is discontinuous and lies between the Clarkston and Camp Creek Formations. Thickness is up to 3 m. Age is Late Proterozoic and (or) early Paleozoic.
Source: GNU records (USGS DDS-6; Reston GNULEX).
The Intrenchment Creek Quartzite of the Atlanta Group is here abandoned because it is a part of the newly named Barrow Hill Formation.
Source: GNU records (USGS DDS-6; Reston GNULEX).
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
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