Geologic units in Heard county, Georgia

Biotite Gneiss (Precambrian-Paleozoic) at surface, covers 33 % of this area

Biotite gneiss

Biotitic Gneiss / Mica Schist/ Amphibolite (Precambrian-Paleozoic) at surface, covers 17 % of this area

Biotitic Gneiss / Mica Schist/ Amphibolite

Mica Schist/ Gneiss (Precambrian-Paleozoic) at surface, covers 15 % of this area

Mica Schist/ Gneiss

Graphite Schist (Precambrian-Paleozoic) at surface, covers 12 % of this area

Graphite Schist

Granitic Gneiss undifferentiated (Precambrian-Paleozoic) at surface, covers 5 % of this area

Granitic Gneiss undifferentiated

Mica Schist/ Quartzite/ Gneiss/ Amphibolite (Precambrian-Paleozoic) at surface, covers 5 % of this area

Mica Schist/ Quartzite/ Gneiss/ Amphibolite

Hornblende Gneiss (Precambrian-Paleozoic) at surface, covers 3 % of this area

Hornblende Gneiss

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

Granite Gneiss/ Granite

Hornblende Gneiss/ Amphibolite (Precambrian-Paleozoic) at surface, covers 2 % of this area

Hornblende Gneiss/ Amphibolite

Garnet Mica Schist/ Gneiss (Precambrian-Paleozoic) at surface, covers 2 % of this area

Garnet Mica Schist/ Gneiss

Biotitic Gneiss / Amphibolite (Precambrian-Paleozoic) at surface, covers 1 % of this area

Biotitic Gneiss / Amphibolite

Amphibolite (Precambrian-Paleozoic) at surface, covers 0.7 % of this area

Amphibolite

Dadeville Complex; Rock Mills Granite Gneiss (Precambrian to Paleozoic) at surface, covers 0.1 % of this area

Coarse to medium-grained biotite granite gneiss; locally includes thick bands of epidote and thin, small amphibolite bodies. Boundary between Rock Mills Granite Gneiss and Camp Hill Granite Gneiss arbitrarily defined.

Emuckfaw Group; Emuckfaw Group undifferentiated in part (Precambrian to Paleozoic) at surface, covers 0.1 % of this area

Interbedded muscovite +/- garnet-biotite schist, metagraywacke, calc-silicate rock, and quartzite; rare thin amphibolite. Includes thin layers of aluminous graphitic schist. Locally sheared to mylonite schist.

Amphibolitic Schist (Precambrian-Paleozoic) at surface, covers 0.1 % of this area

Amphibolitic Schist

Emuckfaw Group; Glenloch Schist (Precambrian to Paleozoic) at surface, covers < 0.1 % of this area

Graphite-garnet-muscovite schist with interlayered metagraywacke.

Wedowee Group; Wedowee Group undifferentiated (Precambrian to Paleozoic) at surface, covers < 0.1 % of this area

Wedowee Group undifferentiated includes the Cragford Phyllite and Cutnose Gneiss. Cragford Phyllite -- interbedded fine-grained graphite-chlorite-sericite schist and phyllite, garnet-sericite schist and phyllite, graphite-quartz-sericite phyllite, locally feldspathic biotite gneiss, calc-silicate rock, and quartzite. Cutnose Gneiss -- cyclically interbedded fine-grained quartz-biotite feldspathic gneiss, graphite-chlorite-sericite schist, locally thin interbeds of graphite-quartz-sericite phyllite, and quartzite. Rocks in the area northeast of Clanton in Chilton and Coosa Counties that are here assigned to the Wedowee Group also have been interpreted as part of the Higgins Ferry Group.

Dadeville Complex; Waresville Schist (Precambrian to Paleozoic) at surface, covers < 0.1 % of this area

Banded amphibolite interlayered with chlorite schist, chlorite amphibolite, chlorite-actinolite schist, chlorite +/- magnetite quartzite, and actinolite quartzite; may include small ultramafic pods.

Ultramafic rocks undifferentiated (Precambrian-Paleozoic) at surface, covers < 0.1 % of this area

Ultramafic rocks undifferentiated

Jacksons Gap Group; Jacksons Gap Group undifferentiated in part (Precambrian to Paleozoic) at surface, covers < 0.1 % of this area

Principally graphitic sericite (muscovite)-quartz schist; includes sericite-quartz phyllonite; sericite phyllonite, blastomylonite, porphyroclastic blastomylonite schist, and mylonite quartzite occur principally along margins in south and form most of unit northeast of Jacksons Gap, Tallapoosa County.

Mylonitic and Cataclastic Rocks in the Brevard, Towaliga, and Goat Rock Fault Zones (Precambrian to Paleozoic) at surface, covers < 0.1 % of this area

Mylonite and blastomylonite; contains minor ultramylonite, mylonite schist, and mylonite gneiss.