Geologic units in Hancock county, Georgia

Granite undifferentiated (Precambrian-Paleozoic) at surface, covers 22 % of this area

Granite undifferentiated

Biotite Granite Gneiss/ Feldspathic Biotite Gneiss/ Amphibolite Hornblende Gneiss (Precambrian-Paleozoic) at surface, covers 20 % of this area

Biotite Granite Gneiss/ Feldspathic Biotite Gneiss/ Amphibolite Hornblende Gneiss

Undifferentiated Metavolcanics/ Sericite phyllite/ Meta-argillite/ Quartz mica schist (Precambrian-Paleozoic) at surface, covers 18 % of this area

Undifferentiated Metavolcanics/ Sericite phyllite/ Meta-argillite/ Quartz mica schist

Irwinton Sand (Eocene) at surface, covers 16 % of this area

Up-dip equivalent of Twiggs Clay, Sandersville Limestone, and Cooper Marl. As mapped, also includes younger clastics of indefinite Late Tertiary age.

Biotite Gneiss/ Feldspathic Biotite Gneiss (Precambrian-Paleozoic) at surface, covers 14 % of this area

Biotite Gneiss/ Feldspathic Biotite Gneiss

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

Quartzite/ Mica Schist

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

Quartz Mica Schist/ Hornblende Schist/ Biotitic Gneiss

Granite/ gneissic biotite granite (Precambrian-Paleozoic) at surface, covers 1 % of this area

Granite/ gneissic biotite granite

Meta-argillite/ Phyllite (Precambrian-Paleozoic) at surface, covers 0.9 % of this area

Meta-argillite/ Phyllite

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

Amphibolite/ Biotitic Gneiss/ Quartz Sericite Schist

Lower Tertiary-Cretaceous undifferentiated (Lower Tertiary-Cretaceous) at surface, covers 0.4 % of this area

As mapped includes Middendorf Formation (Sloan, 1904); "Channel Sands" (LaMoreaux, 1946); Tuscaloosa Formation (Cooke, 1939); and "Huber beds" (Buie, informal terminology)

Porphyritic granite (Precambrian-Paleozoic) at surface, covers 0.3 % of this area

Porphyritic granite

Quartz Sericite Schist/ Biotitic Gneiss (Precambrian-Paleozoic) at surface, covers 0.2 % of this area

Quartz Sericite Schist/ Biotitic Gneiss

Hornblende Gneiss/ Granite Gneiss/ Biotite Gneiss (Precambrian-Paleozoic) at surface, covers < 0.1 % of this area

Hornblende Gneiss/ Granite Gneiss/ Biotite Gneiss

Twiggs Clay (Eocene) at surface, covers < 0.1 % of this area

Twiggs Clay

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

Ultramafic rocks undifferentiated

Biotitic Gneiss / Amphibolite (Precambrian-Paleozoic) at surface, covers < 0.1 % of this area

Biotitic Gneiss / Amphibolite