GEOLOGY ALONG THE TALLADEGA-EMERSON AND CARTERSVILLE-GREAT SMOKY FAULTS: STRATIGRAPHIC, STRUCTURAL, AND KINEMATIC EVIDENCE FOR TWO SEPARATE FAULTS

Historically, boundary faults located between the Blue Ridge and Valley and Ridge in Georgia have been interpreted as a single fault system. This fault system has been shown by previous workers to vary in strike, trending north-south near Cartersville, GA and into Tennessee, where it is referenced as the Cartersville-Great Smoky fault, to nearly east-west across west Georgia and into Alabama where it is referenced as the Emerson-Talladega fault. The first suggestion that the Cartersville-Great Smoky and Emerson -Talladega faults were two separate faults appeared in the literature by Cressler (1979) and Crawford and Cressler (1981). However, this interpretation was not widely accepted.

Detailed geologic mapping of the Cartersville Mining District to the Alabama-Georgia state line was conducted at a 1:24,000-scale. A compilation of our detailed geologic mapping, fourteen 7.5-minute quadrangles, was presented in 2011 by Kath and Crawford. Based on this mapping, lithologic units juxtaposed by the Cartersville-Great Smoky fault are different from those that are juxtaposed by the Emerson-Talladega fault. Units in the hanging wall of the Cartersville-Great Smoky fault are comprised of the Ocoee Supergroup and Corbin Massif; whereas, units in the hanging wall of the Emerson-Talladega fault consist of schist, graphitic schist, and metagraywacke, referred to as the Talladega Belt. Geologic strike of these different units is also parallel with the respective faults, providing stratigraphic as well as structural support for a two-fault interpretation. Detailed kinematic mapping of the fault zones along the shoreline of Lake Allatoona, Georgia has also helped discriminate the fault relationships.

The Cartersville-Great Smoky Fault overrides the basal Cambrian Chihowee Group and Shady Dolomite. After emplacement of the Cartersville-Great Smoky Fault, the Ocoee Supergroup and Corbin Massif structurally overlie the basal Cambrian. Movement along the younger Emerson-Talladega Fault at its juncture with the Cartersville-Great Smoky Fault carried the basal Cambrian and overlying Ocoee/Corbin along a footwall thrust creating a complex tectonostratigraphy exposed along the lake shore (Allatoona Lake) in the Iron Hill Campground area.