Evolution of contourite-drift deposits in the late Quaternary and their interaction with water masses in the Santos basin, Southwestern Atlantic.

Abstract

The main objective of the proposal is to understand the evolution of contourite-drift deposits in the Santos Basin, Brazilian southern margin during the last glacial cycle. The project also aims to evaluate the relationship of these deposits to the Antarctic Intermediate Water (AAIW) and the North Atlantic Deep Water (NADW), seeking to recognize the bottom currents speeds and oceanic productivity changes during different climatic phases, as well as the capacity of preserve of organic matter in sediments slope under AAIW and NADW. For this, multiproxies analysis will be applied: sedimentological (particle size, description of sedimentary facies), geochemical (metals and semi-metals concentrations, composition and carbon and nitrogen isotopes of organic matter; d18O and d13C stable isotopes in calcareous shells of benthic foraminifera), and benthic foraminifera assemblages analyses. The material to be analyzed consists of cores to be collected at stations, which were chosen based on analysis of seismic sections, obtained in Santos Basin, in the project "Geodynamics of Sedimentary Basins and implications for the exploration potential (oil, natural gas and groundwater) - GEOSEDex, funded by the Research Support Center of the University of São Paulo - NAP / USP. (AU)