DIGITAL GEOLOGIC MAPS AND CROSS SECTIONS OF THE 1:24,000 CHOCCOLOCCO QUADRANGLE, NORTHEAST ALABAMA VALLEY AND RIDGE AND TALLADEGA SLATE BELT

We present a digital geologic map of the 1:24,000 Choccolocco Quadrangle, northeast Alabama. The area of the Choccolocco Quadrangle is underlain by rocks of the Valley and Ridge and Piedmont physiographic provinces. Valley and Ridge sedimentary rocks exposed in the area are Cambrian in age. The Piedmont rocks are low-grade meta- sedimentary units of the Talladega slate belt. The Talladega-Cartersville fault marks the contact between the Valley and Ridge and the Talladega slate belt. Basic objectives of the mapping are to gain a better understanding of the following: (1) the Anniston cross-strike structural discontinuity; (2) the nature and significance of the Talladega-Cartersville fault, the southern Appalachian master decollement; and (3) the lithologic and petrologic character of the early Paleozoic rift-to-drift and platformal units and their significance for Laurentian margin evolution.

The computer generated maps and cross sections were developed in the following fashion. The topographic quadrangle and hand-drawn overlays of station localities, structural/fabric data, contacts, and structural traces were scanned as a JPEG or Windows® bitmap file using an IDEAL® FSC 8010, 85 cm wide, color scanner at Auburn University. The scanned image was imported into Corel Designer 9.0® software and digitized using a standard PC and a Wacom® pad and pen. The digitized map and various layers then were printed directly from Corel Designer 9.0® or exported as a Windows® metafile (wmf) into other drawing software packages and printed on an HP Designjet CP Corel Designer 9.0® plotter at Auburn University.