South Pacific dissolved Nd isotope compositions and rare earth element distributions: Water mass mixing versus biogeochemical cycling
Despite its enormous extent and importance for global climate, the South Pacific has been poorly investigated in comparison to other regions with respect to chemical oceanography. Here we present the first detailed analysis of dissolved radiogenic Nd isotopes (εNd) and rare earth elements (REEs) in...
Published in: | Geochimica et Cosmochimica Acta |
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ftoceanrep:oai:oceanrep.geomar.de:22984 2023-05-15T13:50:23+02:00 South Pacific dissolved Nd isotope compositions and rare earth element distributions: Water mass mixing versus biogeochemical cycling Molina-Kescher, Mario Frank, Martin Hathorne, Ed 2014-02-15 text https://oceanrep.geomar.de/id/eprint/22984/ https://oceanrep.geomar.de/id/eprint/22984/1/Molina-Kescher%20et.al.pdf https://doi.org/10.1016/j.gca.2013.11.038 en eng Elsevier https://oceanrep.geomar.de/id/eprint/22984/1/Molina-Kescher%20et.al.pdf Molina-Kescher, M., Frank, M. and Hathorne, E. (2014) South Pacific dissolved Nd isotope compositions and rare earth element distributions: Water mass mixing versus biogeochemical cycling. Geochimica et Cosmochimica Acta, 127 . pp. 171-189. DOI 10.1016/j.gca.2013.11.038 <https://doi.org/10.1016/j.gca.2013.11.038>. doi:10.1016/j.gca.2013.11.038 info:eu-repo/semantics/restrictedAccess Article PeerReviewed 2014 ftoceanrep https://doi.org/10.1016/j.gca.2013.11.038 2023-04-07T15:11:38Z Despite its enormous extent and importance for global climate, the South Pacific has been poorly investigated in comparison to other regions with respect to chemical oceanography. Here we present the first detailed analysis of dissolved radiogenic Nd isotopes (εNd) and rare earth elements (REEs) in intermediate and deep waters of the mid-latitude (∼40°S) South Pacific along a meridional transect between South America and New Zealand. The goal of our study is to gain better insight into the distribution and mixing of water masses in the South Pacific and to evaluate the validity of Nd isotopes as a water mass tracer in this remote region of the ocean. The results demonstrate that biogeochemical cycling (scavenging processes in the Eastern Equatorial Pacific) and release of LREEs from the sediment clearly influence the distribution of the dissolved REE concentrations at certain locations. Nevertheless, the Nd isotope signatures clearly trace water masses including AAIW (Antarctic Intermediate Water) (average εNd = −8.2 ± 0.3), LCDW (Lower Circumpolar Deep Water) (average εNd = −8.3 ± 0.3), NPDW (North Pacific Deep Water) (average εNd = −5.9 ± 0.3), and the remnants of NADW (North Atlantic Deep Water) (average εNd = −9.7 ± 0.3). Filtered water samples taken from the sediment–water interface under the deep western boundary current off New Zealand suggest that boundary exchange processes are limited at this location and highlight the spatial and temporal variability of this process. These data will serve as a basis for the paleoceanographic application of Nd isotopes in the South Pacific. Article in Journal/Newspaper Antarc* Antarctic NADW North Atlantic Deep Water North Atlantic OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) Antarctic New Zealand Pacific Geochimica et Cosmochimica Acta 127 171 189 |
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OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) |
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ftoceanrep |
language |
English |
description |
Despite its enormous extent and importance for global climate, the South Pacific has been poorly investigated in comparison to other regions with respect to chemical oceanography. Here we present the first detailed analysis of dissolved radiogenic Nd isotopes (εNd) and rare earth elements (REEs) in intermediate and deep waters of the mid-latitude (∼40°S) South Pacific along a meridional transect between South America and New Zealand. The goal of our study is to gain better insight into the distribution and mixing of water masses in the South Pacific and to evaluate the validity of Nd isotopes as a water mass tracer in this remote region of the ocean. The results demonstrate that biogeochemical cycling (scavenging processes in the Eastern Equatorial Pacific) and release of LREEs from the sediment clearly influence the distribution of the dissolved REE concentrations at certain locations. Nevertheless, the Nd isotope signatures clearly trace water masses including AAIW (Antarctic Intermediate Water) (average εNd = −8.2 ± 0.3), LCDW (Lower Circumpolar Deep Water) (average εNd = −8.3 ± 0.3), NPDW (North Pacific Deep Water) (average εNd = −5.9 ± 0.3), and the remnants of NADW (North Atlantic Deep Water) (average εNd = −9.7 ± 0.3). Filtered water samples taken from the sediment–water interface under the deep western boundary current off New Zealand suggest that boundary exchange processes are limited at this location and highlight the spatial and temporal variability of this process. These data will serve as a basis for the paleoceanographic application of Nd isotopes in the South Pacific. |
format |
Article in Journal/Newspaper |
author |
Molina-Kescher, Mario Frank, Martin Hathorne, Ed |
spellingShingle |
Molina-Kescher, Mario Frank, Martin Hathorne, Ed South Pacific dissolved Nd isotope compositions and rare earth element distributions: Water mass mixing versus biogeochemical cycling |
author_facet |
Molina-Kescher, Mario Frank, Martin Hathorne, Ed |
author_sort |
Molina-Kescher, Mario |
title |
South Pacific dissolved Nd isotope compositions and rare earth element distributions: Water mass mixing versus biogeochemical cycling |
title_short |
South Pacific dissolved Nd isotope compositions and rare earth element distributions: Water mass mixing versus biogeochemical cycling |
title_full |
South Pacific dissolved Nd isotope compositions and rare earth element distributions: Water mass mixing versus biogeochemical cycling |
title_fullStr |
South Pacific dissolved Nd isotope compositions and rare earth element distributions: Water mass mixing versus biogeochemical cycling |
title_full_unstemmed |
South Pacific dissolved Nd isotope compositions and rare earth element distributions: Water mass mixing versus biogeochemical cycling |
title_sort |
south pacific dissolved nd isotope compositions and rare earth element distributions: water mass mixing versus biogeochemical cycling |
publisher |
Elsevier |
publishDate |
2014 |
url |
https://oceanrep.geomar.de/id/eprint/22984/ https://oceanrep.geomar.de/id/eprint/22984/1/Molina-Kescher%20et.al.pdf https://doi.org/10.1016/j.gca.2013.11.038 |
geographic |
Antarctic New Zealand Pacific |
geographic_facet |
Antarctic New Zealand Pacific |
genre |
Antarc* Antarctic NADW North Atlantic Deep Water North Atlantic |
genre_facet |
Antarc* Antarctic NADW North Atlantic Deep Water North Atlantic |
op_relation |
https://oceanrep.geomar.de/id/eprint/22984/1/Molina-Kescher%20et.al.pdf Molina-Kescher, M., Frank, M. and Hathorne, E. (2014) South Pacific dissolved Nd isotope compositions and rare earth element distributions: Water mass mixing versus biogeochemical cycling. Geochimica et Cosmochimica Acta, 127 . pp. 171-189. DOI 10.1016/j.gca.2013.11.038 <https://doi.org/10.1016/j.gca.2013.11.038>. doi:10.1016/j.gca.2013.11.038 |
op_rights |
info:eu-repo/semantics/restrictedAccess |
op_doi |
https://doi.org/10.1016/j.gca.2013.11.038 |
container_title |
Geochimica et Cosmochimica Acta |
container_volume |
127 |
container_start_page |
171 |
op_container_end_page |
189 |
_version_ |
1766253445552013312 |