DIGITAL GEOLOGIC MAP OF THE TATE-MARBLE HILL WINDOW AND THE NORTHEASTERN END OF THE CORBIN-SALEM CHURCH CULMINATION, JASPER AND NELSON 7.5-MIN QUADRANGLES, GEORGIA, VER 1.3

Detailed geologic mapping of most of the Jasper and Nelson, 7.5-min quadrangles shows that the area is several orders of magnitude more geologically complicated than previous work has indicated. The Tate-Marble Hill window (TMHW), exposes a multiply folded duplex consisting of five thrust sheets, the Cartersville, Great Smoky, Nantahala, Marble Hill, and Hayesville thrust sheets. The window is framed by the Holly Springs thrust sheet. The Holly Springs thrust sheet also frames the Corbin-Salem Church culmination. The floor thrust for both the Corbin-Salem Church culmination and TMHW is the Cartersville fault. The Bent Tree window, north of the TMHW, may be connected to the TMHW. The Bent Tree window exposes the Padgett Falls Member of the Nantahala Formation, Hickory Cove schist, and biotite mylonite gneiss whose protolith is interpreted to have been part of the Grenville basement complex. The previously unrecognized Bent Tree window was depicted by all previous workers as either Carolina Gneiss or Great Smoky Group undivided. Study of drill-cores shows that the Long Swamp Creek marble and Marble Hill amphibolite exposed in the Marble Hill thrust sheet, TMHW, are metasedimentary rocks deposited together and without the intervening unconformity proposed by some workers. The metasedimentary marble and metavolcanic-epiclastic amphibolite show all gradations from calcareous amphibolite to amphibole-rich marble through a contact zone as thick as 200 ft. Ongoing geologic mapping in the Jasper and Nelson, 7.5-min quadrangles, Ga., has been compiled into an extensive database in Microsoft Access and ESRI's ArcView 3.2. Base maps are digital raster graphics (U.S. Geological Survey). Structural symbols are placed and angle of strike and trend set by a database connection between Microsoft Access and ArcView. The geologic map was printed on a Hewlett-Packard 750C plotter using ESRI's ArcPress for ArcView.