Peter Swarzenski, Ph.D
United States Geological Survey, Pacific Sciences Center
Examining Coastal Groundwater Discharge Using Geochemical Tracers, Seepage Meters, and Electrical Resistivity
Wednesday - October 29, 2008
Pacific Forum – 3:00 p.m.
It is now recognized that submarine groundwater discharge (SGD), an almost ubiquitous coastal process, may substantially impact certain near-shore material budgets. While the contribution of SGD-derived nutrients can vary widely depending on both local hydrogeologic conditions and anthropogenic perturbations, accurate assessments of the spatial and temporal distribution of SGD along a particular coastline remain mostly scarce. This paucity of reliable data stems in large part in that SGD is the ‘hidden’ vector in water and material transport from land to the sea, and that the physical drivers of SGD are complex, often inter-related, and still poorly constrained.
This talk presents field measurements of 222Rn and 223,224,226,228Ra, in addition to electromagnetic seepage meter results, and multi-electrode, stationary and marine resistivity profiles, to identify and quantify submarine groundwater discharge at select sites from California, Washington, Florida, Alaska, and Israel.