Saltwater Intrusion and Structural Controls Within the Groundwater System of St. Catherines Island

Learn about saltwater intrusion and structural controls in groundwater systems through this conference presentation from the Georgia Water Resources Conference, where Dr. James Reichard presents findings from a long-term hydrogeologic study on St. Catherines Island, Georgia. Explore data collected from 24 shallow and 6 deep monitoring wells in the surficial aquifer, examining how periodic saltwater intrusion events correlate with unusually large tides. Discover how geophysical data reveals fractures, faults, and sag structures that influence groundwater movement. Understand the hypothesis that pre-modern artesian groundwater flow created solution caverns along regional joint and fault trends, which later collapsed to form sag structures. Examine evidence suggesting saline water movement through these structural features during large tidal events, and learn how vertical faults and solution collapse features facilitate the upward movement of more saline water from the Lower Floridan aquifer, potentially linked to recurrent movement of Mesozoic basement structures beneath the coastal plain sedimentary sequence.