Geology of the southernmost Piedmont from Columbus to Junction City, GA
- Columbus Coll., GA (United States). Dept. of Chemistry and Geology
Mapping in the Piedmont from the Chattahoochee River to Junction City, GA, is critical to understanding contacts with Southern Appalachian outboard terranes, relationships to the Piedmont allochthon, strike slip displacements along major faults and late Paleozoic and post Paleozoic tectonic activity. Three major map units defining a large synform are recognized in western Muscogee County: the North Columbus Migmatite Complex, the Moffitts Mill Schist (MMS), and the Phenix City gneiss. The distinctive but poorly exposed fine grained feldspar augen MMS, which extends at least as far east as Geneva, contains small enclaves of amphibolite and calcsilicate and large enclaves of lineated granitoid gneiss. Protomylonites and mylonitic gneiss with a N-S to N45E strike are exposed from Geneva to Junction City. Three brecciated quartz dikes transect the area in eastern Muscogee Co. and Talbot Co., converging on Talbotton from the southwest. The northern dike strikes ENE and is associated with an augen schist; the middle dike strikes NE and projects to the southwest deep into Muscogee County as a silicified fracture zone with minor associated granite. The southern dike has a NNE strike and is parallel to and locally silicifies the mylonitic foliation that dominates gneisses to the east. Deflections of the magnetic anomaly patterns to the northeast in the Geneva - Junction City area are parallel to quartz dikes and mylonitic foliations.
- OSTI ID:
- 6119797
- Report Number(s):
- CONF-9304188-; CODEN: GAAPBC
- Journal Information:
- Geological Society of America, Abstracts with Programs; (United States), Vol. 25:4; Conference: 42. annual Geological Society of America (GSA) Southeastern Section meeting, Tallahassee, FL (United States), 1-2 Apr 1993; ISSN 0016-7592
- Country of Publication:
- United States
- Language:
- English
Similar Records
The Chunky Gal Mountain fault-detachment-normal fault providing evidence for Early-to-Middle Paleozoic extensional unroofing of the eastern Blue Ridge, or folded thrust
New geological studies of the most southern part of the Brevard zone, Alabama: Tectonic implications