Efficient Extraction of Past Seawater Pb and Nd Isotope Signatures From Southern Ocean Sediments
Radiogenic lead (Pb) and neodymium (Nd) isotope compositions extracted from authigenic phases in marine sediments are sensitive tracers to reconstruct past ocean circulation and water mass mixing. Chemical reductive leaching of hydrogenetic ferromanganese oxyhydroxides from bulk sediments is the mos...
Published in: | Geochemistry, Geophysics, Geosystems |
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Online Access: | https://doi.org/10.23689/fidgeo-4380 http://resolver.sub.uni-goettingen.de/purl?gldocs-11858/8726 |
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ftsubggeo:oai:e-docs.geo-leo.de:11858/8726 2023-05-15T13:42:31+02:00 Efficient Extraction of Past Seawater Pb and Nd Isotope Signatures From Southern Ocean Sediments Huang, H. Gutjahr, M. Kuhn, G. Hathorne, Ed C. Eisenhauer, A. Gutjahr, M.; 1 GEOMAR Helmholtz Centre for Ocean Research Kiel Kiel Germany Kuhn, G.; 2 Alfred‐Wegener‐Institut Helmholtz‐Zentrum für Polar‐ und Meeresforschung Bremerhaven Germany Hathorne, Ed C.; 1 GEOMAR Helmholtz Centre for Ocean Research Kiel Kiel Germany Eisenhauer, A.; 1 GEOMAR Helmholtz Centre for Ocean Research Kiel Kiel Germany 2021-03-16 https://doi.org/10.23689/fidgeo-4380 http://resolver.sub.uni-goettingen.de/purl?gldocs-11858/8726 eng eng doi:10.23689/fidgeo-4380 http://resolver.sub.uni-goettingen.de/purl?gldocs-11858/8726 This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. CC-BY ddc:551.9 Fe‐Mn oxyhydroxides Nd isotopes Pb isotopes reductive leaching sediment Southern Ocean doc-type:article 2021 ftsubggeo https://doi.org/10.23689/fidgeo-4380 2022-11-09T06:51:38Z Radiogenic lead (Pb) and neodymium (Nd) isotope compositions extracted from authigenic phases in marine sediments are sensitive tracers to reconstruct past ocean circulation and water mass mixing. Chemical reductive leaching of hydrogenetic ferromanganese oxyhydroxides from bulk sediments is the most practical way to recover past seawater Pb and Nd isotope signatures in the Southern Ocean, due to the scarcity of alternative archives. However, the leached signal could be compromised if substantial quantities of Pb and Nd were released from non‐hydrogenetic sediment fractions during chemical extraction. Here we developed a very short 10‐s leaching method to extract reliable seawater Pb and Nd isotope signals from sediments in the Atlantic sector of Southern Ocean. The effect of a previously recommended MgCl2 pre‐wash, the role of chelate ligands in the leaching solution and length of leaching time were investigated. The results show that 10‐s exposure time of sediments to reductive leaching extracted sufficient and more reliable hydrogenetic Pb and Nd compared with the commonly used 30‐min leaching approaches. The robustness of our improved leaching method was validated via direct comparison of Pb and Nd isotope signatures with actual seawater, porewater, and corresponding sediment leachates from three stations in front of the Antarctic Filchner‐Rønne Ice Shelf. Our findings also indicate that in contrast previously studied sites on the West Antarctic continental shelf, the bottom seawater Nd concentration is less elevated through benthic fluxes in the area of the southern Weddell Sea shelf. Plain Language Summary: Individual modern ocean water masses can often be identified by the isotopic signature of dissolved trace metals lead (Pb) and neodymium (Nd) supplied from surrounding continents. By analyzing past seawater Pb and Nd isotope ratios preserved in the sedimentary archives, we can understand how the ocean circulation changed. In the Southern Ocean, archives preserving past seawater Pb and Nd isotope ... Article in Journal/Newspaper Antarc* Antarctic Ice Shelf Southern Ocean Weddell Sea GEO-LEOe-docs (FID GEO) Antarctic Southern Ocean The Antarctic Weddell Sea Weddell Geochemistry, Geophysics, Geosystems 22 3 |
institution |
Open Polar |
collection |
GEO-LEOe-docs (FID GEO) |
op_collection_id |
ftsubggeo |
language |
English |
topic |
ddc:551.9 Fe‐Mn oxyhydroxides Nd isotopes Pb isotopes reductive leaching sediment Southern Ocean |
spellingShingle |
ddc:551.9 Fe‐Mn oxyhydroxides Nd isotopes Pb isotopes reductive leaching sediment Southern Ocean Huang, H. Gutjahr, M. Kuhn, G. Hathorne, Ed C. Eisenhauer, A. Gutjahr, M.; 1 GEOMAR Helmholtz Centre for Ocean Research Kiel Kiel Germany Kuhn, G.; 2 Alfred‐Wegener‐Institut Helmholtz‐Zentrum für Polar‐ und Meeresforschung Bremerhaven Germany Hathorne, Ed C.; 1 GEOMAR Helmholtz Centre for Ocean Research Kiel Kiel Germany Eisenhauer, A.; 1 GEOMAR Helmholtz Centre for Ocean Research Kiel Kiel Germany Efficient Extraction of Past Seawater Pb and Nd Isotope Signatures From Southern Ocean Sediments |
topic_facet |
ddc:551.9 Fe‐Mn oxyhydroxides Nd isotopes Pb isotopes reductive leaching sediment Southern Ocean |
description |
Radiogenic lead (Pb) and neodymium (Nd) isotope compositions extracted from authigenic phases in marine sediments are sensitive tracers to reconstruct past ocean circulation and water mass mixing. Chemical reductive leaching of hydrogenetic ferromanganese oxyhydroxides from bulk sediments is the most practical way to recover past seawater Pb and Nd isotope signatures in the Southern Ocean, due to the scarcity of alternative archives. However, the leached signal could be compromised if substantial quantities of Pb and Nd were released from non‐hydrogenetic sediment fractions during chemical extraction. Here we developed a very short 10‐s leaching method to extract reliable seawater Pb and Nd isotope signals from sediments in the Atlantic sector of Southern Ocean. The effect of a previously recommended MgCl2 pre‐wash, the role of chelate ligands in the leaching solution and length of leaching time were investigated. The results show that 10‐s exposure time of sediments to reductive leaching extracted sufficient and more reliable hydrogenetic Pb and Nd compared with the commonly used 30‐min leaching approaches. The robustness of our improved leaching method was validated via direct comparison of Pb and Nd isotope signatures with actual seawater, porewater, and corresponding sediment leachates from three stations in front of the Antarctic Filchner‐Rønne Ice Shelf. Our findings also indicate that in contrast previously studied sites on the West Antarctic continental shelf, the bottom seawater Nd concentration is less elevated through benthic fluxes in the area of the southern Weddell Sea shelf. Plain Language Summary: Individual modern ocean water masses can often be identified by the isotopic signature of dissolved trace metals lead (Pb) and neodymium (Nd) supplied from surrounding continents. By analyzing past seawater Pb and Nd isotope ratios preserved in the sedimentary archives, we can understand how the ocean circulation changed. In the Southern Ocean, archives preserving past seawater Pb and Nd isotope ... |
format |
Article in Journal/Newspaper |
author |
Huang, H. Gutjahr, M. Kuhn, G. Hathorne, Ed C. Eisenhauer, A. Gutjahr, M.; 1 GEOMAR Helmholtz Centre for Ocean Research Kiel Kiel Germany Kuhn, G.; 2 Alfred‐Wegener‐Institut Helmholtz‐Zentrum für Polar‐ und Meeresforschung Bremerhaven Germany Hathorne, Ed C.; 1 GEOMAR Helmholtz Centre for Ocean Research Kiel Kiel Germany Eisenhauer, A.; 1 GEOMAR Helmholtz Centre for Ocean Research Kiel Kiel Germany |
author_facet |
Huang, H. Gutjahr, M. Kuhn, G. Hathorne, Ed C. Eisenhauer, A. Gutjahr, M.; 1 GEOMAR Helmholtz Centre for Ocean Research Kiel Kiel Germany Kuhn, G.; 2 Alfred‐Wegener‐Institut Helmholtz‐Zentrum für Polar‐ und Meeresforschung Bremerhaven Germany Hathorne, Ed C.; 1 GEOMAR Helmholtz Centre for Ocean Research Kiel Kiel Germany Eisenhauer, A.; 1 GEOMAR Helmholtz Centre for Ocean Research Kiel Kiel Germany |
author_sort |
Huang, H. |
title |
Efficient Extraction of Past Seawater Pb and Nd Isotope Signatures From Southern Ocean Sediments |
title_short |
Efficient Extraction of Past Seawater Pb and Nd Isotope Signatures From Southern Ocean Sediments |
title_full |
Efficient Extraction of Past Seawater Pb and Nd Isotope Signatures From Southern Ocean Sediments |
title_fullStr |
Efficient Extraction of Past Seawater Pb and Nd Isotope Signatures From Southern Ocean Sediments |
title_full_unstemmed |
Efficient Extraction of Past Seawater Pb and Nd Isotope Signatures From Southern Ocean Sediments |
title_sort |
efficient extraction of past seawater pb and nd isotope signatures from southern ocean sediments |
publishDate |
2021 |
url |
https://doi.org/10.23689/fidgeo-4380 http://resolver.sub.uni-goettingen.de/purl?gldocs-11858/8726 |
geographic |
Antarctic Southern Ocean The Antarctic Weddell Sea Weddell |
geographic_facet |
Antarctic Southern Ocean The Antarctic Weddell Sea Weddell |
genre |
Antarc* Antarctic Ice Shelf Southern Ocean Weddell Sea |
genre_facet |
Antarc* Antarctic Ice Shelf Southern Ocean Weddell Sea |
op_relation |
doi:10.23689/fidgeo-4380 http://resolver.sub.uni-goettingen.de/purl?gldocs-11858/8726 |
op_rights |
This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.23689/fidgeo-4380 |
container_title |
Geochemistry, Geophysics, Geosystems |
container_volume |
22 |
container_issue |
3 |
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1766168895915294720 |