Thrust faults mark the boundary between sedimentary Ridge and Valley province(s) of western Appalachia and metamorphic Blue Ridge and Piedmont provinces of the eastern slopes. During the assembly of Pangea about 300 million years ago, Pre-Cambrian metamorphic rocks derived from the Iapetus basin were thrust over Cambrian to Pennsylvanian sediments derived from Proto-North America, producing the stratigraphic awkwardness of older rocks lying above younger rocks. In Georgia, this boundary was long considered to be a single fault family, the Cartersville Fault. Closer study suggests that two faults intersect near Carterville, Georgia, in a distorted loop around the Corbin meta-granite. These faults are currently called the Carters Dam Fault and the Emerson Fault. Of course, neither fault is a single simple fault; they include splays and imbricate thrust layers.
The Carters Dam Fault runs north from Cartersville into Tennessee, approximately parallel to and just east of U.S. Highway 411. The fault's main trace is clearly exposed in a cut below Carters Dam, on the north side of the Coosawattee River.
The Emerson Fault, a continuation of Alabama's Talladega Fault, runs east-northeast from Alabama past Cartersville, where it appears to truncate the Carters Dam Fault but may not. The fault runs roughly parallel to other northeast-trending faults in Georgia, and near them in some areas, but it is not clear how or if they connect.
For further information on northwest boundary faults, consult: