DEFINING THE MINERAL POTENTIAL OF UPPER COASTAL PLAIN SEDIMENTS IN SOUTHWESTERN GEORGIA THROUGH DETAILED QUADRANGLE MAPPING

Upper Coastal Plain sediments exposed in southwestern Georgia range in age from Upper Cretaceous to Miocene. Mineral deposits developed at various times include kaolin, bauxite, limestone, iron ore, plus sand and gravel. Currently, only kaolin, bauxite, and sand are being mined. Additional potential exists for heavy minerals. Previous studies, as well as recent geologic mapping supported through the USGS sponsored STATEMAP program, define kaolin and bauxite deposits and potential heavy mineral deposits and the host Upper Paleocene Nanafalia Formation. Iron ore and limestone deposits are found in the Lower Paleocene Clayton Formation. Sand and gravel, used mainly for road construction and repair, has been mined from the Upper Cretaceous Providence Formation, the Claiborne Group, and the Miocene Altamaha Formation. Geologic mapping defines the distribution of each stratigraphic unit, specific occurrences of certain mineral deposits (e.g. kaolin and bauxite), geologic indications of perhaps concealed mineral deposits (e.g. large bauxite and kaolin clasts), as well as unconformable relations that may have resulted in genesis of the mineral deposit (e.g. iron ore and bauxite – kaolin) or actual removal of the mineral deposit. Digital GIS map compilations permit querying of the database to develop derivative geologic maps that highlight potential mineral-hosting stratigraphic units.