Variability in the accumulation of siliciclastic sediments off southeastern South America during the last 8,000 years

• Grant number: 11/12246-9
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2011
• End date: August 31, 2012
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Geology
• Principal Investigator: Cristiano Mazur Chiessi
• Grantee: Marília de Carvalho Campos Garcia
• Host Institution: Escola de Artes, Ciências e Humanidades (EACH). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

A strong increase in precipitation over southeastern South America (SESA) has been projected for the coming decades. This increase may produce significant damage and losses in the urban and rural environments as well as intensification in continental erosion and sediment supply to the western subtropical South Atlantic. Studying the effects that past major changes in precipitation over SESA had on the sediment supply to the marine realm may help reducing the substantial uncertainties related to the future behavior of continental erosion. Here we propose to reconstruct the accumulation rate of siliciclastic sediments at the continental slope off SESA during the last 8,000 years. Our main aim is to check if key periods of changes in precipitation over SESA (e.g., Mid Holocene, Late Holocene) were related to variations in erosion and siliciclastic sediment supply to the western subtropical South Atlantic. This goal will be achieved via extensive 14C AMS age determinations of planktic foraminiferal samples from sediment cores raised between 27 and 39oS off SESA. (AU)