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Dadeville Complex; Mafic and ultramafic rock

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.
State Alabama
Name Dadeville Complex; Mafic and ultramafic rock
Geologic age Precambrian to Paleozoic
Comments from the USGS Geologic Names lexicon (ref. AL002): Dadeville Complex intruded by the informally named Franklin gneiss, a metamorphosed and deformed batholith-scale granite pluton with abundant outcrops in Heard Co., west-central GA. An Rb-Sr whole rock age of 462+/-4 Ma (Middle Ordovician) on the Franklin provides a minimum age constraint for Dadeville rocks.
Primary rock type pyroxenite
Secondary rock type amphibolite
Other rock types hornblendite
Lithologic constituents
Major
Igneous > Plutonic > Ultramafic > Pyroxeniteultramafic rock including enstatite pyroxenite
Minor
Metamorphic > Amphibolite (Amphibolite)layered actinolite-tremolite amphibolite altered locally to serpentine, anthophyllite, and talc; and massive amphibolite.
Metamorphic > Metaigneous > Metaintrusivemetanorite; metagabro
Incidental
Igneous > Plutonic > Ultramafic > Hornblenditehornblendite; garnet-hornblendite
Map references
Szabo, M. W., Osborne, E. W., Copeland, C. W. Jr., Neathery; T. L., 1988, Geologic Map of Alabama, Geological Survey of Alabama Special Map 220, scale 1:250,000.
Unit references
Szabo, M. W., Osborne, E. W., Copeland, C. W. Jr., Neathery; T. L., 1988, Geologic Map of Alabama, Geological Survey of Alabama Special Map 220, scale 1:250,000.
USGS Geologic Names Lexicon (GEOLEX)
Counties Chambers - Tallapoosa