Geologic Map of Georgia
Legend


For now this legend contains only text codes, not pattern images. Maybe later. Also, I have omitted non-English typography (e.g. double-staff "P" for Pennsylvanian) in the belief that the reader will correctly interpret symbols in context (and because I don't know how to program them, yet).


Ridge and Valley
Sedimentary Rocks

(in stratigraphic order, more-or-less)
. . .
. Pennsylvanian Pu Pennsylvanian undifferentiated
. . Ps Sewanee Sandstone (Lookout Sandstone)
. . Pg Gizzard Formation (Lookout Sandstone)
. Mississippian Mu Mississipian undifferentiated
. . Mb Bangor Limestone
. . Mfs Floyd Shale
. . Mh Hartselle Sandstone (Floyd Shale)
. . Ml Un-named limestone member (Floyd Shale)
. . Mfp Fort Payne Chert
. . Mls Lavender Shale (Fort Payne Chert)
. Devonian DMu Devonian-Mississipian undivided
. . Dc Chattanooga Shale
. . Dfm Frog Mountain Chert
. . Da Armuchee Chert
. Silurian Srm Red Mountain Formation
. Ordovician Oc Chickamauga Group undivided
. . Oum Upper and middle Ordovician rocks (Chickamauga Group)
. . Omb Bays Formation (Chickamauga Group)
. . Och Chota Formation (Chickamauga Group)
. . Oh Holston Limestone (Chickamauga Group)
. . Oa Athens Shale (middle Ordovician)
. . Or Rockmart Slate (middle Ordovician)
. . Ol Lenoir Limestone (middle Ordovician)
. . OCk Knox Group undifferentiated
. . On Newala Limestone (Knox Group)
. Cambrian Ccr Copper Ridge Dolomite (Knox Group)
. . Ccm Maynardville Limestone (Conasauga Group)
. . Ccsl Upper Unit, Conasauga Group -- limestone and shale
. . Ccd Upper Unit, Conasauga Group -- dolostone
. . Ccls Middle Unit, Conasauga Group -- limestone
. . Cc Middle Unit, Conasauga Group -- shale
. . Ccs Lower Unit, Conasauga Group -- shale and sandstone
. . Ccdl Lower Unit, Conasauga Group -- dolostone
. . Cr Rome Formation
. . Cs Shady Dolomite
. . Cch Chilhowee Formation
Blue Ridge and Piedmont
Crystalline Rocks

(no stratigraphic order implied)
. . .
. Granites gr1 Granite undifferentiated
. . gr1a Non-porphyritic Granite
. . gr1b Porphyritic Granite
. . gr2 Granite / Granite Gneiss
. . gr2a Granite / Gneissic Biotite Granite
. . gr3 Granite / Biotitic Gneiss / Amphibolite
. . gr4 Charnockite
. . gr5 Syenite
. Granite Gneiss gg1 Granitic Gneiss undifferentiated
. . gg2 Granite Gneiss / Gneissic Granite (Augen or Porphyritic)
. . gg3 Muscovite Granite Gneiss
. . gg4 Granite Gneiss / Amphibolite
. . gg5 Calc-silicate Granite Gneiss
. . gg6 Granite Gneiss / Granite
. Intermediate Gneiss fg1 Biotite Gneiss / Felspathic Biotite Gneiss
. . fg1a Biotite Granite Gneiss / Felspathic Biotite Gneiss / Amphibolite-Hornblende Gneiss
. . fg2 Biotitic Gneiss undifferentiated
. . fg3 Biotitic Gneiss / Mica Schist / Amphibolite
. . fg4 Biotitic Gneiss / Amphibolite
. Biotite Gneiss bg1 Biotite Gneiss
. . bg2 Biotite Gneiss / Amphibolite
. . bg3 Biotite Gneiss / Hornblende Gneiss / Granite Gneiss
. . bg4 Biotite Gneiss / Mica Schist
. Metamorphosed Mafic Rocks
(May include metasedimentary varieties)
mm1 Amphibolite
. mm2 Hornblende Gneiss
. mm3 Hornblende Gneiss / Amphibolite
. mm4 Hornblende Gneiss / Amphibolite / Granite Gneiss
. mm5 Hornblende-Biotite Gneiss / Amphibolite
. . mm6 Hornblende Gneiss / Granite Gneiss / Biotite Gneiss
. . mm7 Amphibolite / Epidote Quartzite / Granite Gneiss
. . mm8 Amphibolite / Biotitic Gneiss / Quartz Sericite Schist
. . mm9 Amphibolite / Mica Schist / Biotitic Gneiss
. . mm10 Amphibolite / Metagraywacke / Mica Schist
. . mm11 Mafic Hornfels
. Mafic Schists ms1 Amphibolitic Schist
. . ms2 Amphibolitic Schist / Amphibolite
. . ms3 Amphibolitic Schist / Amphibolite / Metagraywacke / Mica Schist
. Metagraywacke pm1 Metagraywacke undifferentiated
. . pm2 Metagraywacke / Mica Schist
. . pm3 Metagraywacke / Mica Schist / Calc-Silicate Gneiss
. . pm3a Metagraywacke / Mica Schist / Quartzite / Amphibolite
. . pm4 Mica Schist / Metasiltstone
. . pm5 Slate / Quartzite / Conglomerate
. . pm6 Conglomerate
. Mica Schist pms1 Mica Schist
. . pms2 Mica Schist / Amphibolite
. . pms3 Mica Schist / Gneiss
. . pms3a Mica Schist / Gneiss / Amphibolite
. . pms4 Mica Schist / Quartzite / Gneiss / Amphibolite
. . pms5 Graphite Schist
. . pms6 Sericite Schist
. . pms6a Sericite Schist / Amphibolite
. . pms6b Sericite Schist / Abmphibolite / Granite Gneiss
. . pms6c Sericite Schist / Micaceous Quartzite / Sericite Phyllite
. . pms6d Quartz Sericite Schist / Biotitic Gneiss
. . pms6e Quartz Mica Schist / Hornblende Schist / Biotitic Gneiss
. . pms7 Button Mica Schist
. . pms8 Cross-Biotite Schist
. Pelitic and Calcareous Rocks mu Undifferentiated Pelitic Rocks
(includes mica schists, metasiltstones. metaconglomerates, and metagraywackes)
. m1 Marble
. . m2 Calcareous Mica Schist / Micaceous Marble / Mica Schist
. Phyllitic Rocks pp1 Phyllite undifferentiated
. . pp1a Meta-Argillite / Phyllite
. . pp2 Graphitic Phyllite
. . pp3 Phyllite and Quartzite
. . pp3a Phyllite / Quartzite / Calc-Silicate Gneiss
. Aluminous Schist pg1 Garnet Mica Schist
. . pg2 Garnet Mica Schist / Gneiss
. . pg3 Garnet Mica Schist / Amphibolite
. . pa1 Aluminous Schist
. . pa2 Sillimanite Schist
. . pa2a Sillimanite Schist / Gneiss
. . pa2b Sillimanite Schist / Gneiss / Amphibolite
. . pa2c Sillimanite Schist / Amphibolite
. Quartzite q1 Quartzite
. . q1a Quartzite / Mica Schist
. . q1b Quartzite / Mica Schist / Amphibolite
. . q1c Quartzite / Metagraywacke
. . q1d Quartzite / Phyllite
. . q2 Quartzite / Biotite Granite Gneiss
. . q3 Epidote Quartzite / Amphibolite / Sericite Schist / biotite Granite Gneiss
. Cataclastic Rocks c1 Mylonite and Ultramylonite
. . c2 Flinty Crush Rock
. Metavolcanic Rocks v1 Mafic to Intermediate Metavolcanic Rocks
. . v2 Metadacite
. . v3 Felsic Metavolcanics
. . v4 Undifferentiated Metavolcanics / Sericite Phyllite / Meta-Argillite / Quartz Mica Schist
. . v5 Meta-Argillite / Sericite Phyllite / Metavolcanics
. Mafic and Ultramafic Rocks um Ultramafic Rocks undifferentiated
. mp1 Amphibolite / Gabbro
. . mp2 Gabbro
. . mp3 Amphibolite / Ultramafic
. . d Diabase
Coastal Plain
Sedimentary Rocks

(in stratigraphic order, more-or-less)
. . .
. Holocene Qal Stream alluvium and undifferentiated terrace deposits
. . Qpd Aeolian sand -- parabolic dunes
. . Qas Aeolian sand -- formless deposits
. . Qhm Holocene shoreline complex -- marsh and lagoon facies
. . Qhi Holocene shoreline complex -- barrier island facies
. Pleistocene Qsbi Silver Bluff shoreline complex -- barrier island facies
. . Qpam Princess Anne shoreline complex -- marsh and lagoon facies
. . Qpai Princess Anne shoreline complex -- barrier island facies
. . Qpm Pamlico shoreline complex -- marsh and lagoon facies
. . Qpi Pamlico shoreline complex -- barrier island facies
. . Qtm Talbot shoreline complex -- marsh and lagoon facies
. . Qti Talbot shoreline complex -- barrier island facies
. . Qpnm Penholoway shoreline complex -- marsh and lagoon facies
. . Qpni Penholoway shoreline complex -- barrier island facies
. . Qwm Wicomico shoreline complex -- marsh and lagoon facies
. . Qwi Wicomico shoreline complex -- barrier island facies
. . PPs Pleistocene - Pliocene sands and gravels
. Pliocene Pcd Charlton Formation and Duplin Marls
. . Nm Miccosukee Formation (Neogene)
. . Nu Neogene undifferentiated
. Miocene Mh "Hawthorn Formation"
. Oligocene Os Suwanee Limestone and its residuum
. Eocene Es-Os Eocene and Oligocene residuum, undifferentiated
. . Ei Irwinton Sand
. . Ecm "Cooper Marl"
. . Es Sandersville Limestone
. . Etw Twiggs Clay
. . Eu Eocene undifferentiated
. . Eo Ocala Limestone
. . Ecl Clinchfield Sand
. . Eli Lisbon Formation
. . Em McBean Formation
. . Ec Claiborne undifferentiated
. . Eta Tallahatta Formation
. Paleocene Ptu Tuscahoma Sand
. . Pnf Nanfalia Formation
. . Pcn Nanfalia, Porters Creek, and Clayton Formations, undifferentiated
. . Pc Clayton Formation
. . TKu Lower Tertiary - Cretaceous, undifferentiated
. Cretaceous Kp Providence Sand, including Perote member
. . Kr Ripley Formation
. . Kc Cusseta Sand
. . Kcbe Cusseta, Blufftown, and Eutaw Formations, undifferentiated
. . Kb Blufftown Formation
. . Ke Eutaw Formation
. . Kt Tuscaloosa Formation

Return to: