Radiocarbon geochronology of the sediments of the Sao Paulo Bight (southern Brazilian upper margin)

Autor(es)

Mahiques, Michel M. ^[1] ; Sousa, Silvia H. M. ^[1] ; Burone, Leticia ^[1] ; Nagai, Renata H. ^[1] ; Silveira, Ilson C. A. ^[1] ; Figueira, Rubens C. L. ^[1] ; Soutelino, Rafael G. ^[1] ; Ponsoni, Leandro ^[1] ; Klein, Daniel A. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Oceanog, BR-05508120 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Anais da Academia Brasileira de Ciências; v. 83, n. 3, p. 817-834, SEP 2011.
• Citações Web of Science: 24

Resumo

The aim of this work was to generate an inventory of the data on radiocarbon datings obtained from sediments of the Sao Paulo Bight (southern Brazilian upper margin) and to analyze the data in terms of Late Quaternary sedimentary processes and sedimentation rates. A total of 238 radiocarbon datings from materials collected using different sampling procedures was considered for this work. The sedimentation rates varied from less than 2 to 68 cm. kyr(-1). The highest sedimentation rate values were found in a low-energy (ria type) coastal system as well as in the upwelling zones of Santa Catarina and Cabo Frio. The lowest rates were found on the outer shelf and upper slopes. Our results confirm the strong dependency of the shelf currents, with an emphasis to the terrigenous input from the Rio de La Plata outflow which is transported via the Brazilian Coastal Current, as well as of the coupled Brazil Current - Intermediate Western Boundary Current (BC-IWBC) dynamics on the sedimentary processes. At least three indicators of the paleo sea level were found at 12200 yr BP (conventional radiocarbon age) (103 meters below sea level - mbsl), 8300-8800 cal yr BP (13 mbsl) and 7700-8100 cal yr BP (6 mbsl). (AU)

• Processo FAPESP: 03/10740-0 - Variações holocênicas na paleoprodutividade da Plataforma Continental Sudeste do Brasil
• Beneficiário: Michel Michaelovitch de Mahiques
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 07/54657-0 - Mudanças na produtividade e na circulação oceânica da margem continental sul-sudeste brasileira durante o Holoceno: evidências micropaleontológicas e geoquímicas
• Beneficiário: Silvia Helena de Mello e Sousa
• Modalidade de apoio: Auxílio à Pesquisa - Regular