Control of oceanic circulation on sediment distribution in the southwestern Atlantic margin (23 to 55° S)
In this study, we interpret the role played by ocean circulation in sediment distribution on the southwestern Atlantic margin using radiogenic Nd and Pb isotopes. The latitudinal trends for Pb and Nd isotopes reflect the different current systems acting on the margin. The utilization of the sediment...
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ftcopernicus:oai:publications.copernicus.org:os94601 2023-05-15T14:02:17+02:00 Control of oceanic circulation on sediment distribution in the southwestern Atlantic margin (23 to 55° S) Michaelovitch de Mahiques, Michel Violante, Roberto Franco-Fraguas, Paula Burone, Leticia Barbedo Rocha, Cesar Ortega, Leonardo Felicio dos Santos, Rosangela Mi Kim, Bianca Sung Lopes Figueira, Rubens Cesar Caruso Bícego, Marcia 2021-09-15 application/pdf https://doi.org/10.5194/os-17-1213-2021 https://os.copernicus.org/articles/17/1213/2021/ eng eng doi:10.5194/os-17-1213-2021 https://os.copernicus.org/articles/17/1213/2021/ eISSN: 1812-0792 Text 2021 ftcopernicus https://doi.org/10.5194/os-17-1213-2021 2021-09-20T16:22:27Z In this study, we interpret the role played by ocean circulation in sediment distribution on the southwestern Atlantic margin using radiogenic Nd and Pb isotopes. The latitudinal trends for Pb and Nd isotopes reflect the different current systems acting on the margin. The utilization of the sediment fingerprinting method allowed us to associate the isotopic signatures with the main oceanographic features in the area. We recognized differences between Nd and Pb sources to the Argentinean shelf (carried by the flow of Subantarctic Shelf Water) and slopes (transported by deeper flows). Sediments from Antarctica extend up to the Uruguayan margin, carried by the Upper and Lower Circumpolar Deep Water. Our data confirm that, for shelf and intermediate areas (the upper 1200 m ), the transfer of sediments from the Argentinean margin to the north of 35 ∘ S is limited by the Subtropical Shelf Front and the basin-wide recirculated Antarctic Intermediate Water. On the southern Brazilian inner and middle shelf, it is possible to recognize the northward influence of the Río de la Plata sediments carried by the Plata Plume Water. Another flow responsible for sediment transport and deposition on the outer shelf and slope is the southward flow of the Brazil Current. Finally, we propose that the Brazil–Malvinas Confluence and the Santos Bifurcation act as boundaries of geochemical provinces in the area. A conceptual model of sediment sources and transport is provided for the southwestern Atlantic margin. Text Antarc* Antarctic Antarctica Copernicus Publications: E-Journals Antarctic Ocean Science 17 5 1213 1229 |
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Open Polar |
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Copernicus Publications: E-Journals |
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ftcopernicus |
language |
English |
description |
In this study, we interpret the role played by ocean circulation in sediment distribution on the southwestern Atlantic margin using radiogenic Nd and Pb isotopes. The latitudinal trends for Pb and Nd isotopes reflect the different current systems acting on the margin. The utilization of the sediment fingerprinting method allowed us to associate the isotopic signatures with the main oceanographic features in the area. We recognized differences between Nd and Pb sources to the Argentinean shelf (carried by the flow of Subantarctic Shelf Water) and slopes (transported by deeper flows). Sediments from Antarctica extend up to the Uruguayan margin, carried by the Upper and Lower Circumpolar Deep Water. Our data confirm that, for shelf and intermediate areas (the upper 1200 m ), the transfer of sediments from the Argentinean margin to the north of 35 ∘ S is limited by the Subtropical Shelf Front and the basin-wide recirculated Antarctic Intermediate Water. On the southern Brazilian inner and middle shelf, it is possible to recognize the northward influence of the Río de la Plata sediments carried by the Plata Plume Water. Another flow responsible for sediment transport and deposition on the outer shelf and slope is the southward flow of the Brazil Current. Finally, we propose that the Brazil–Malvinas Confluence and the Santos Bifurcation act as boundaries of geochemical provinces in the area. A conceptual model of sediment sources and transport is provided for the southwestern Atlantic margin. |
format |
Text |
author |
Michaelovitch de Mahiques, Michel Violante, Roberto Franco-Fraguas, Paula Burone, Leticia Barbedo Rocha, Cesar Ortega, Leonardo Felicio dos Santos, Rosangela Mi Kim, Bianca Sung Lopes Figueira, Rubens Cesar Caruso Bícego, Marcia |
spellingShingle |
Michaelovitch de Mahiques, Michel Violante, Roberto Franco-Fraguas, Paula Burone, Leticia Barbedo Rocha, Cesar Ortega, Leonardo Felicio dos Santos, Rosangela Mi Kim, Bianca Sung Lopes Figueira, Rubens Cesar Caruso Bícego, Marcia Control of oceanic circulation on sediment distribution in the southwestern Atlantic margin (23 to 55° S) |
author_facet |
Michaelovitch de Mahiques, Michel Violante, Roberto Franco-Fraguas, Paula Burone, Leticia Barbedo Rocha, Cesar Ortega, Leonardo Felicio dos Santos, Rosangela Mi Kim, Bianca Sung Lopes Figueira, Rubens Cesar Caruso Bícego, Marcia |
author_sort |
Michaelovitch de Mahiques, Michel |
title |
Control of oceanic circulation on sediment distribution in the southwestern Atlantic margin (23 to 55° S) |
title_short |
Control of oceanic circulation on sediment distribution in the southwestern Atlantic margin (23 to 55° S) |
title_full |
Control of oceanic circulation on sediment distribution in the southwestern Atlantic margin (23 to 55° S) |
title_fullStr |
Control of oceanic circulation on sediment distribution in the southwestern Atlantic margin (23 to 55° S) |
title_full_unstemmed |
Control of oceanic circulation on sediment distribution in the southwestern Atlantic margin (23 to 55° S) |
title_sort |
control of oceanic circulation on sediment distribution in the southwestern atlantic margin (23 to 55° s) |
publishDate |
2021 |
url |
https://doi.org/10.5194/os-17-1213-2021 https://os.copernicus.org/articles/17/1213/2021/ |
geographic |
Antarctic |
geographic_facet |
Antarctic |
genre |
Antarc* Antarctic Antarctica |
genre_facet |
Antarc* Antarctic Antarctica |
op_source |
eISSN: 1812-0792 |
op_relation |
doi:10.5194/os-17-1213-2021 https://os.copernicus.org/articles/17/1213/2021/ |
op_doi |
https://doi.org/10.5194/os-17-1213-2021 |
container_title |
Ocean Science |
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17 |
container_issue |
5 |
container_start_page |
1213 |
op_container_end_page |
1229 |
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1766272462227505152 |