PRELIMINARY DIGITAL GEOLOGIC MAP OF PART OF THE PIEDMONT AND BLUE RIDGE IN GEORGIA

Geologic maps of the Atlanta, Athens, and Griffin 1-degree x 30-minute quadrangles and parts of the Anniston, Cartersville, LaGrange, Commerce, Thomaston, Milledgeville, and Toccoa 1-degree x 30-minute quadrangles have been digitized into ESRI’s ArcView 8.2 GIS program, joined, edge-matched, and printed at a scale of 1:250,000. Geologic mapping in the Atlanta and parts of the Cartersville quadrangles is mostly detailed, whereas mapping in the other quadrangles is mostly detailed reconnaissance and reconnaissance. The combined maps will be generalized to provide a lithologic base for the U.S. Geological Survey’s Urban Land Use Gradient (ULUG) Project of the NAWQA Program. The map will also be finished as a geologic map to form part of a future Geologic Map of the Appalachians in Georgia by the Geologic Mapping Institute. Structural databases for the map and field checks of critical areas have not yet been completed. In addition, the explanation for the complex geology of the combined map area has not yet been completed. The combined geologic map spans from the Coastal Plain unconformity in the Thomaston and Milledgeville quadrangles, across the Pine Mountain window, Piedmont, Brevard fault zone, across the Dog Rive window, the Allatoona allochthon, and the western Blue Ridge, and into the eastern Valley and Ridge.