Title: A Conceptual Model of the Hydrogeologic Function of Coastal Terraces and Beach Ridges on the Southeast Georgia Coastal Plain
Presenters: Kaitlyn N. Williams
Faculty Supervisor: Dr. James Deemy
Abstract: Coastal terraces and beach ridges are geologic features frequently used to map relict shorelines and trace historic global sea-level change. The southeastern Georgia coastal plain is a physiographic region dominated by sedimentary and hydrologic processes. Accordingly, these features can be rich in economically-relevant minerals which can lead to mining operations along relict beach ridges. However, the hydrogeologic functions of terrace & ridge sequences are not well-defined, thus it is difficult to predict the impacts of mining operations. Our objectives were 1) to review and synthesize the current research on terraces and beach ridges of the southeast Georgia Coastal plain; and 2) propose a conceptual model of hydrogeologic function of these features to highlight research needs, particularly those regarding impacts of mining efforts in this physiographic province. Our conceptual model of the hydrogeologic function of coastal terraces and beach ridges incorporates the following elements: 1) coastal terraces and beach ridges as critical geomorphic features of the southeastern Georgia coastal plain; and 2) coastal terrace and beach ridge influence on local watershed hydrogeologic attributes (drainage, porosity, runoff). Our review and conceptual model indicate that coastal terrace and beach ridge mining likely impacts surface hydrogeology of local watersheds, namely freshwater wetlands, but the severity of such impacts will depend on a variety of local factors.