Geologic units in Towns county, Georgia

Biotite Gneiss (Precambrian-Paleozoic) at surface, covers 79 % of this area

Biotite gneiss

Garnet Mica Schist (Precambrian-Paleozoic) at surface, covers 10 % of this area

Garnet Mica Schist

Amphibolite/ Ultramafic (Precambrian-Paleozoic) at surface, covers 8 % of this area

Amphibolite/ Ultramafic

Mica Schist/ Gneiss (Precambrian-Paleozoic) at surface, covers 3 % of this area

Mica Schist/ Gneiss

Coweeta Group; Biotite Gneiss (Middle/Late Proterozoic) at surface, covers 0.2 % of this area

Migmatitic; interlayered and gradational with biotite-garnet gneiss and amphibolite; locally abundant quartz and alumino-silicates. Stratigraphic position uncertain.

Quartzite (Precambrian-Paleozoic) at surface, covers < 0.1 % of this area

Quartzite

Ocoee Supergroup, Great Smokey Group; Metasandstone, Metagraywacke, Metasiltstone, and Mica Schist (Late Proterozoic) at surface, covers < 0.1 % of this area

Beds and lenses of calc-silicate rock locally abundant; garnet, staurolite, and cross-biotite porphyroblasts common in fine-grained layers. Includes Hughes Gap and Hothouse formations in southern area; Horse Branch Member of Ammons Formation and Grassy Branch Formation in northern area.

Ocoee Supergroup; Great Smokey Group, undivided (Late Proterozoic) at surface, covers < 0.1 % of this area

Thick metasedimentary sequence of massive to graded beds of metagraywacke and metasiltstone with interbedded graphitic and sulfidic slate and schist.

Ocoee Supergroup, Great Smokey Group; Copperhill Formation (Late Proterozoic) at surface, covers < 0.1 % of this area

Metagraywacke, massive, graded bedding common; includes dark-gray slate, mica schist, and nodular calc-silicate rock.

Ocoee Supergroup, Great Smokey Group; Wehutty Formation (Late Proterozoic) at surface, covers < 0.1 % of this area

Slate to schist, dark gray, graphitic and sulfidic; includes mica schist, metagraywacke, and metaconglomerate.

Coweeta Group; Amphibolite (Middle/Late Proterozoic) at surface, covers < 0.1 % of this area

Equigranular, massive to well foliated, interlayered, rarely discordant, metamorphosed intrusive to extrusive mafic rock; may include metasedimentary rock.

Meta-ultramafic Rock (Paleozoic/Late Proterozoic) at surface, covers < 0.1 % of this area

Metamorphosed dunite, local peridotite; serpentinite, soapstone, and other altered ultramafic rock. Only larger bodies shown.

Ocoee Supergroup, Great Smokey Group; Dean Formation (Late Proterozoic) at surface, covers < 0.1 % of this area

Sericite schist with cross-biotite, staurolite, and garnet porphyroblasts; interbedded metagraywacke and quartz-pebble metaconglomerate.

Quartzite/ Mica Schist (Precambrian-Paleozoic) at surface, covers < 0.1 % of this area

Quartzite/ Mica Schist