UNDERGRADUATE CREATIVE INQUIRY: GEOLOGIC MAPPING IN THE CLEMSON EXPERIMENTAL FOREST

As part of the undergraduate research experience (creative inquiry) now required of Clemson geology majors, we have initiated a geologic investigation of the Clemson Experimental Forest (CEF). The CEF consists of 17,500 acres of woodland bordering the campus of Clemson University and is managed as a multiuse working forest. The goal of our project is to prepare a digitized geologic map of the CEF. For the past four semesters we have collected field data in the northern portion of the forest. Individual outcrops were located using GPS and incorporated into a GIS database, along with information on rock type and attitude (strike and dip). The recent drought in the southeastern US had significantly lowered the water level in adjoining Lake Hartwell, exposing many rocks normally hidden underwater, so a concerted effort was made to sample along the lake’s shoreline. Biotite gneiss is the principal rock type, with subordinate hornblende gneiss (amphibolite) and mica schist. Thin sections were prepared from selected samples and examined with a petrographic microscope to characterize the mineral assemblages present. The occurrence of key metamorphic minerals such as garnet and sillimanite is noteworthy as they constrain the metamorphic history of the rocks. Compositions of coexisting garnet and biotite were obtained with an electron microprobe to further delimit temperatures attained during metamorphism. The pressure-temperature data retrieved from the metamorphic minerals in the rocks will provide a framework for interpreting the tectonic history of the Piedmont region of the southern Appalachians.