This award supports the analysis of calcareous nannofossil assemblages from high quality DSDP/ODP drill cores from the South Atlantic to help reconstruct the thermal gradient of surface waters of that basin for the Maestrichtian to Miocene time interval (74 to 5 million years ago). The investigation will characterize major surface water masses and infer from biological gradients latitudinal thermal gradients that can be compared against those derived independently from stable isotope techniques. This should provide new insights into the thermal structure of the oceans through time. Such data have important implications for studies that attempt to reconstruct changes in the global heat budget and the deterioration of Cenozoic climates that accompanied the progressive isolation of the Antarctic continent. The study will record in detail latitudinal shifts in surface water masses through time as a means of tracing steps in the deterioration of global climates. //
