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

Geologic units in Tallapoosa county, Alabama

Hatchet Creek Group; Pinchoulee Gneiss (Precambrian to Paleozoic) at surface, covers 0.4 % of this area

Pinchoulee Gneiss - medium to fine-grained migmatitic, locally garnetiferous biotite-feldspar gneiss, commonly saturated with granitic pods.

Lithology: felsic gneiss; granite

Zana Granite (Precambrian to Paleozoic) at surface, covers 5 % of this area

Zana Granite - quartz monzonite to granite with strong gneissic texture, cut by small pegmatites and aplite dikes, generally elongate; semiconcordant to foliation of country rock.

Lithology: quartz monzonite; granite; pegmatite; aplite

Dadeville Complex; Camp Hill Granite Gneiss (Precambrian to Paleozoic) at surface, covers 11 % 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.

Lithology: granitic gneiss; amphibolite

Kowaliga Gneiss (Precambrian to Paleozoic) at surface, covers 5 % of this area

Kowaliga Gneiss - coarse-grained granodiorite to quartz monzonite with large plagioclase augen; generally shared among margins.

Lithology: granodiorite; quartz monzonite

Wedowee Group; Hackneyville Schist (Precambrian to Paleozoic) at surface, covers 3 % of this area

Hackneyville Schist - medium to coarse-grained quartz-plagioclase +/- almandine +/- kyanite +/- biotite-muscovite schist, graphite-muscovite-quartz schist, and quartzite containing biotite. Large porphyroblasts of muscovite, andalusite and/or chiastrolite common. Rocks in the areas between Goodwater in Coosa County and Millerville in Clay County that are here assigned to the Hackneyville Schist also have been interpreted as part of the Higgins Ferry Group.

Lithology: schist; quartzite

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

High terrace deposits - 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.

Lithology: terrace

Dadeville Complex; Rock Mills Granite Gneiss (Precambrian to Paleozoic) at surface, covers 2 % of this area

Rock Mills Granite Gneiss - 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.

Lithology: granitic gneiss; amphibolite

Elkahatchee Quartz Diorite Gneiss (Precambrian to Paleozoic) at surface, covers 11 % of this area

Elkahatchee Quartz Diorite Gneiss - mesocratic to melanocratic, fine to coarse-grained, massive to strongly foliated, locally sheared quartz diorite gneiss.

Lithology: orthogneiss

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

Ropes Creek Amphibolite - layered and massive amphibolite; locally includes hornblende migmatite and ultramafic pods.

Lithology: amphibolite; migmatite; ultramafic intrusive rock

Wedowee Group; Cornhouse Schist (Precambrian to Paleozoic) at surface, covers 4 % of this area

Cornhouse Schist - medium to coarse-grained multiply foliated +/- plagioclase +/- garnet-biotite-muscovite-quartz schist interlayed with chlorite-biotite-garnet schist, typically mylonitic.

Lithology: schist

Beaverdam Amphibolite (Precambrian to Paleozoic) at surface, covers < 0.1 % of this area

Beaverdam Amphibolite - dark-green to dark-gray hornblende amphibolite, extensively sheared and folded, and locally retrograded to actinolite-tremolite-chlorite schist. Includes all amphibolite associated with the Wedowee Group.

Lithology: amphibolite; schist

Jacksons Gap Group; Jacksons Gap Group, Unnamed unit (Precambrian to Paleozoic) at surface, covers 0.6 % of this area

Jacksons Gap Group; Jacksons Gap Group, Unnamed unit - unnamed comprised of masses of interbedded grayish-green sericite phyllite and sericite-quartz-chlorite phyllite.

Lithology: phyllite

Dadeville Complex; Mafic and ultramafic rock (Precambrian to Paleozoic) at surface, covers 4 % of this area

Mafic and ultramafic rock - ultramafic rock including enstatite pyroxenite, layered actinolite-tremolite amphibolite altered locally to serpentine, anthophyllite, and talc; metanorite; metagabbro; hornblendite; garnet-hornblendite, and massive amphibolite.

Lithology: pyroxenite; amphibolite; hornblendite

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

Loachapoka Schist - 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.

Lithology: mica schist; quartzite

Dadeville Complex; Agricola Schist (Precambrian to Paleozoic) at surface, covers 8 % of this area

Agricola Schist - biotiite +/- garnet +/- sillimanite-feldspar-quartz schist, interlayered with thin-bedded dark-brown hornblende amphibolite; contains pegmatite pods and veins.

Lithology: quartz-feldspar schist; amphibolite; pegmatite

Wedowee Group; Wedowee Group undifferentiated (Precambrian to Paleozoic) at surface, covers 5 % of this area

Wedowee Group undifferentiated - 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.

Lithology: schist; phyllite; felsic gneiss; quartzite; calc-silicate rock

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

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

Lithology: mafic gneiss; amphibolite; quartzite; mica schist; calc-silicate rock

Jacksons Gap Group; Jacksons Gap Group undifferentiated in part (Precambrian to Paleozoic) at surface, covers 5 % of this area

Jacksons Gap Group undivided - 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.

Lithology: schist; phyllonite; mylonite; quartzite

Alluvial, coastal and low terrace deposits (Holocene) at surface, covers 0.6 % of this area

Alluvial, coastal and low terrace deposits - 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.

Lithology: beach sand; alluvium

Bluff Springs Granite (Precambrian to Paleozoic) at surface, covers 0.1 % of this area

Bluff Springs Granite - leucocratic quartz diorite (tonalite) to quartz monzonite or trondhjemite, locally foliated.

Lithology: tonalite; quartz monzonite; trondhjemite

Tuscaloosa Group undifferentiated (Cretaceous) at surface, covers 4 % of this area

Tuscaloosa Group undifferentiated - 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.

Lithology: sand; clay or mud; sandstone; gravel; quartzite

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

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

Lithology: amphibolite; schist; quartzite; ultramfic intrusive rock

Emuckfaw Group; Emuckfaw Group undifferentiated in part (Precambrian to Paleozoic) at surface, covers 9 % of this area

Emuckfaw Group undifferentiated in part - 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.

Lithology: mica schist; metasedimentary rock; quartzite; calc-silicate rock; amphibolite

Jacksons Gap Group; Tallassee Metaquartzite (Precambrian to Paleozoic) at surface, covers 0.2 % of this area

Jacksons Gap Group; Tallassee Metaquartzite - medium to fine-grained, massive to thin-bedded quartzite and metaconglomerate and thin beds of graphitic quartz schist, locally contains small garnets.

Lithology: quartzite; meta-conglomerate; schist

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

Mylonitic and Cataclastic Rocks in the Brevard, Towaliga, and Goat Rock Fault Zones - mylonite and blastomylonite; contains minor ultramylonite, mylonite schist, and mylonite gneiss.

Lithology: mylonite; schist; gneiss