This award will enable Dr. Robert B. Dunbar of Rice University to collaborate with Dr. Peter Barrett of the Victoria University of Wellington, New Zealand. They will work on developing a quantitative sedimentation model for the McMurdo Sound area of the Ross Sea, Antarctica. Sediment sources, transport paths and accumulation rates will be examined via geochemical and micropaleontologic characterization of sediment trap and seafloor sediment samples, as well as lead-210 analysis of accumulation rates using sediment cores. The Ross Sea/McMurdo Sound area is the most extensively sampled region of the Antarctic shelf with respect to coring and drilling. A quantitative working model of shelf sedimentation is a prerequisite for accurate interpretation of the sediment record from these piston cores and drill cores. Drs. Dunbar and Barrett have ongoing field programs in the Antarctic. Their collaboration in developing a quantitative model of sedimentation processes will have utility in validating geochemical cycles and budgets, not only for the area of McMurdo Sound, but on a global scale.