In this project, the PI will study the principal water masses of the South Atlantic Ocean, and attempt to map their spreading routes through the basin. Historical hydrographic data from the National Oceanographic Data Center archive will be augmented by new data from the South Atlantic Ventilation Experiment (SAVE) and the World Ocean Circulation Experiment (WOCE), which include new tracer data. These tracers will allow new interpretations, which were previously inaccessible to temperature and salinity data alone.