The Norris Lake Schist Member is here named the lower member of the Snellville Formation in the Newnan-Tucker synform near Atlanta, GA. It consists of interlayered garnet-biotite-muscovite schist, hornblende-plagioclase amphibolite, and minor biotite gneiss and quartzite. Discordantly overlies the Lithonia Gneiss and Atlanta Group; underlies the Lanier Mountain Quartzite Member of the Snellville. Thickness is 30 m. Age is Late Proterozoic and (or) early Paleozoic.
Source: GNU records (USGS DDS-6; Reston GNULEX).
The Norris Lake Schist Member of the Snellville Formation of Higgins and Atkins (1981) is here abandoned because it is shown to be part of the Powers Ferry Formation of the Sandy Springs Group [Now Powers Ferry Member of Stonewall Gneiss].
Source: GNU records (USGS DDS-6; Reston GNULEX).
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
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