INVESTIGATION OF SEDIMENT PROVENANCE, BEAVERDAM CREEK DELTA, LAKE WYLIE, NC

The southeastern United States experienced an historic drought in 2007. As a consequence Lake Wylie, an impoundment on the Catawba River, reached record low levels and the Beaverdam Creek delta in Brown's Cove was subaerially exposed. The UNC Charlotte sedimentology class extracted 5 cores (ranging in length from 140 to 288 centimeters) from the delta using a Livingstone coring system. The mineralogy of the cores is being examined in order to determine provenance of the sediments. Heavy minerals extracted using sodium polytungstate are being examined with petrographic microscopes. Common heavy minerals include ilmenite, hematite, magnetite, spinel, kyanite and epidote, consistent with the geology underlying Beaverdam Creek watershed. A quantitative study of the heavy minerals is underway in order to determine the relative contributions of portions of the watershed underlain by gabbro versus granite. Samples are also being analyzed using a Rigaku Miniflex XRD. Common fine-grained minerals are kaolinite and quartz. Additional core samples from the delta, and soil samples from within the watershed, are being analyzed to determine the variety, and possibly provenance, of the clay minerals. Changes in provenance of the heavy and clay minerals may record the history of disturbance within the developing Beaverdam Creek watershed.