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Mineral Resources > Online Spatial Data > Geology > by state > Georgia Geology

Geologic units in McDuffie county, Georgia

Meta-argillite/ Sericite phyllite/ Metavolcanics (Precambrian-Paleozoic) at surface, covers 5 % of this area

Meta-argillite/ Sericite phyllite/ Metavolcanics

Lithology: metasedimentary rock; phyllite; metavolcanic rock

Granite undifferentiated (Precambrian-Paleozoic) at surface, covers 13 % of this area

Granite undifferentiated

Lithology: granite

Twiggs Clay (Eocene) at surface, covers 1 % of this area

Twiggs Clay

Lithology: clay or mud

Sericite Schist (Precambrian-Paleozoic) at surface, covers 9 % of this area

Sericite Schist

Lithology: schist

Lower Tertiary-Cretaceous undifferentiated (Lower Tertiary-Cretaceous) at surface, covers 22 % of this area

Lower Tertiary-Cretaceous undifferentiated, as mapped includes Middendorf Formation (Sloan, 1904); "Channel Sands" (LaMoreaux, 1946); Tuscaloosa Formation (Cooke, 1939); and "Huber beds" (Buie, informal terminology)

Lithology: sand; clay or mud

Meta-argillite/ Phyllite (Precambrian-Paleozoic) at surface, covers 2 % of this area

Meta-argillite/ Phyllite

Lithology: metasedimentary rock; phyllite

Irwinton Sand (Eocene) at surface, covers 5 % of this area

Irwinton Sand (Ei), up-dip equivalent of Twiggs Clay, Sandersville Limestone, and Cooper Marl. As mapped, also includes younger clastics of indefinite Late Tertiary age.

Lithology: sand

Quartz Sericite Schist/ Biotitic Gneiss (Precambrian-Paleozoic) at surface, covers 0.3 % of this area

Quartz Sericite Schist/ Biotitic Gneiss

Lithology: schist; biotite gneiss

Amphibolite/ Biotitic Gneiss/ Quartz Sericite Schist (Precambrian-Paleozoic) at surface, covers 0.4 % of this area

Amphibolite/ Biotitic Gneiss/ Quartz Sericite Schist

Lithology: amphibolite; biotite gneiss; schist

Granitic Gneiss undifferentiated (Precambrian-Paleozoic) at surface, covers 26 % of this area

Granitic Gneiss undifferentiated

Lithology: granitic gneiss

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

Quartzite/ Mica Schist

Lithology: quartzite; mica schist

Sericite Schist/ Amphibolite/ Granite gneiss (Precambrian-Paleozoic) at surface, covers 3 % of this area

Sericite Schist/ Amphibolite/ Granite gneiss

Lithology: schist; amphibolite; granitic gneiss

Granite Gneiss/ Amphibolite (Precambrian-Paleozoic) at surface, covers 9 % of this area

Granite Gneiss/ Amphibolite

Lithology: granitic gneiss; amphibolite

Felsic Metavolcanics (Precambrian-Paleozoic) at surface, covers 3 % of this area

Felsic Metavolcanics

Lithology: felsic metavolcanic rock