TEACHING ABOUT THE GEOLOGY OF THE CAPE FEAR RIVER BASIN

Teaching about the geology and hydrology of the Cape Fear River Basin is a challenge because the rocks are generally not visible. At UNC-Pembroke, the official audience for upper-level geology courses is science education majors, so one of my broad goals is to provide them with local information that they may be able to use in their own teaching. By exploiting the literature, I have developed teaching materials that expose students to key elements of the Cape Fear geologic framework.

One exercise set investigates the aquifer system of the Cape Fear Basin and vicinity, using figures modified from the U.S.G.S. Hydrologic Atlas. The set comprises exercises on 1) subsurface stratigraphy of regional Cretaceous-Cenozoic aquifers; 2) the tectonic effects of the Cape Fear Arch through deep time; and 3) student interpretation of groundwater flowpaths in Cretaceous aquifers. For the groundwater segments, students compare their interpretation to conclusions of the N.C. Department of Environmental Resources.

A second exercise evaluates Quaternary vegetation and climate change based on David Frey’s studies of pollen from Carolina Bay lakes. The base of the record begins with a diverse pollen assemblage, similar to today, representing a previous interglacial. In the transition to the last glacial, diversity falls considerably and most trees (e.g., sweet gum, bald cypress) disappear, while pine becomes more abundant and the lycopod quillwort appears. Then a deglaciation sequence occurs marked by re-appearance of the trees with an increase in Compositae near the surface. Students divide the record into major intervals, compare the vegetation record of each, and make climate interpretations. Finally, they are asked to decide if a climax or equilibrium vegetation can be identified. An additional benefit is that students learn that Quaternary changes in the Cape Fear region were profound even though this area was remote from ice sheets.