Geologic units in Lee county, Alabama

Tuscaloosa Group undifferentiated (Cretaceous) at surface, covers 21 % of this area

Light-gray to moderate-reddish-orange clayey, gravelly fine to very coarse sand; massive mottled sandy clay; local wood and leaf beds; and thin beds of indurated sandstone. Gravel consists mainly of quartz and quartzite and range in size from very fine pebbles to large cobbles. Mapped eats of the Tallapoosa River.

Mylonitic and Cataclastic Rocks in the Brevard, Towaliga, and Goat Rock Fault Zones (Precambrian to Paleozoic) at surface, covers 12 % of this area

Blastomylonite, mylonite gneiss, locally includes mylonite schist and mylonite quartzite in Towaliga fault zone.

Dadeville Complex; Ropes Creek Amphibolite (Precambrian to Paleozoic) at surface, covers 8 % of this area

Layered and massive amphibolite; locally includes hornblende migmatite and ultramafic pods.

Opelika Complex; Auburn Gneiss, Unnamed unit (Precambrian to Paleozoic) at surface, covers 6 % of this area

Unnamed unit comprised of masses of medium- to coarse-grained muscovite-biotite schist, locally garnetiferous; grades into oa.

Wacoochee Complex; Whatley Mill Gneiss (Precambrian to Paleozoic) at surface, covers 6 % of this area

Variably mylonitized coarse-grained biotite-muscovite-oligoclase gneiss with large potassium feldspar augen.

Opelika Complex; Auburn Gneiss (Precambrian to Paleozoic) at surface, covers 6 % of this area

Fine-grained biotite-oligoclase gneiss intermixed with coarse-grained muscovite-biotite schist; locally contains muscovite-rich pegmatite.

Opelika Complex; Bottle Granite (Precambrian to Paleozoic) at surface, covers 5 % of this area

Leucocratic, fine to medium-grained, well-foliated quartz monzonite to granite; locally porphyritic.

Pine Mountain Group; Manchester Schist (Precambrian to Paleozoic) at surface, covers 5 % of this area

Interlayered muscovite-quartz schist and quartzite, locally contains garnet, sillimanite and graphite; commonly intensely shared.

Opelika Complex; Loachapoka Schist (Precambrian to Paleozoic) at surface, covers 4 % of this area

Muscovite-quartz schist; locally contains biotite-garnet-muscovite schist, many layers conatin sillimanite (northeast of Mount Jefferson, Lee County); kyanite (west of Mount Jefferson); locally muscovite-rich schist and quartzite common.

Wacoochee Complex; Halawaka Schist (Precambrian to Paleozoic) at surface, covers 4 % of this area

Feldspathic muscovite-biotite schist and quartz-diorite gneiss; locally contains lenses of muscovite-graphite schist and amphibolite; commonly cut by feldspathic veins and pegmatites.

Motts Gneiss (Precambrian to Paleozoic) at surface, covers 4 % of this area

Leucocratic quartz-rich quartz diorite pencil gneiss.

Uchee Complex; Phenix City Gneiss (Precambrian to Paleozoic) at surface, covers 4 % of this area

Biotite-epidote quartz diorite gneiss and biotite-hornblende gneiss; locally includes migmatitic amphibolite; cut by numerous granitic veins.

Dadeville Complex; Waverly Gneiss (Precambrian to Paleozoic) at surface, covers 3 % of this area

Feldspathic biotite-hornblende gneiss with thin layers of amphibolite, calc-silicate rock, garnet quartzite, and muscovite schist; locally rich in manganese.

Eutaw Formation (Cretaceous) at surface, covers 3 % of this area

Light-greenish-gray to yellowish-gray cross-bedded, well-sorted, micaceous, fine to medium quartz sand that is fossiliferous and glauconitic in part and contains beds of greenish-gray micaceous, silty clay and medium-dark-gray carbonaceous clay. Light-gray glauconitic fossiliferous sand, thin beds of sandstone, and massive accumulations of fossil oyster shells occur locally in the upper part of the formation in western AL (Tombigbee Sand Member). In eastern AL thin to thick-bedded accumulations of the fossil oyster Ostrea cretacea Morton occur throughout much of the formation.

Pine Mountain Group; Hollis Quartzite (Precambrian to Paleozoic) at surface, covers 3 % of this area

Quartzite containing minor mica, feldspar, and pyrite; locally arkosic; commonly sheared.

Mylonitic and Cataclastic Rocks in the Brevard, Towaliga, and Goat Rock Fault Zones (Precambrian to Paleozoic) at surface, covers 2 % of this area

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

Alluvial, coastal and low terrace deposits (Holocene) at surface, covers 1 % of this area

Varicolored fine to coarse quartz sand containing clay lenses and gravel in places. Gravel composed of quartz and chert pebbles and assorted metmorphic and igneous rock fragments in streams near the Piedmont. In areas of the Valley and Ridge province gravel composed of angular to subrounded chert, quartz, and quartzite pebbles. Coastal deposits include fine to medium quartz sand with shell fragments and accessory heavy minerals along Gulf beaches and fine to medium quartz sand, silt, clay, peat, mud and ooze in the Mississippi Sound, Little Lagoon, bays, lakes, streams, and estuaries.

Wacoochee Complex; Phelps Creek Gneiss (Precambrian to Paleozoic) at surface, covers 1.0 % of this area

Quartz monzonite to granite gneiss in dikes and sheets with wide migmatite zones at contacts.

Dadeville Complex; Camp Hill Granite Gneiss (Precambrian to Paleozoic) at surface, covers 0.7 % of this area

Camp Hill Granite Gneiss - coarse to medium-grained foliated granite to quartz diorite (tonalite) gneiss, locally biotite-rich; locally contains thin amphibolite pods and lenses. Boundary between Rock Mills Granite Gneiss and Camp Hill Granite Gneiss arbitrarily defined.

Motts Gneiss, Unnamed unit (Precambrian to Paleozoic) at surface, covers 0.3 % of this area

Unnamed unit comprised of masses of epidote-hornblende-oligoclase mylonitic gneiss and amphibolite.

Mylonitic and Cataclastic Rocks in the Brevard, Towaliga, and Goat Rock Fault Zones (Precambrian to Paleozoic) at surface, covers 0.2 % of this area

Crushed schistose rock; includes sericite-graphite-rich rocks.

Moffits Mill Schist (Precambrian to Paleozoic) at surface, covers 0.1 % of this area

Interlayered biotite-epidote-muscovite-quartz schist, metagraywacke, and quartzite.

Pine Mountain Group; Chewacla Marble (Precambrian to Paleozoic) at surface, covers 0.1 % of this area

Light-gray coarse to fine-grained dolomite marble; locally rich in phlogopite.

Uchee Complex; Hospilika Granite (Precambrian to Paleozoic) at surface, covers < 0.1 % of this area

Leucocratic, massive epidote-muscovite quartz diorite to granodiorite; weak flow banding, sharp contacts.

High terrace deposits (Pleistocene) at surface, covers < 0.1 % of this area

Varicolored lenticular beds of poorly sorted sand, ferruginous sand, silt, clay, and gravelly sand. Sand consists primarily of very fine to very coarse poorly sorted quartz grains; gravel composed of quartz, quartzite, and chert pebbles.

Mylonite and ultramylonite (Age uncertain) at surface, covers < 0.1 % of this area

Mylonite and ultramylonite

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

Biotite gneiss