Influence of intense scavenging on Pa-Th fractionation in the wake of Kerguelen Island (Southern Ocean)
International audience Dissolved and particulate excess 230Th and 231Pa concentrations (noted 230Thxs and 231Paxs respectively) and 231Paxs/230Thxs activity ratios were investigated on and out of the Kerguelen plateau (Southern Ocean) in the framework of the Kerguelen Ocean and Plateau compared Stud...
Published in: | Biogeosciences |
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Main Authors: | , , , , , |
Other Authors: | , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
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HAL CCSD
2011
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Online Access: | https://hal.science/hal-04511731 https://hal.science/hal-04511731/document https://hal.science/hal-04511731/file/Venchiarutti%20et%20al2011.pdf https://doi.org/10.5194/bg-8-3187-2011 |
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HAL-CEA (Commissariat à l'énergie atomique et aux énergies alternatives) |
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language |
English |
topic |
[SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography [CHIM.OTHE]Chemical Sciences/Other [CHIM.RADIO]Chemical Sciences/Radiochemistry |
spellingShingle |
[SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography [CHIM.OTHE]Chemical Sciences/Other [CHIM.RADIO]Chemical Sciences/Radiochemistry Venchiarutti, C Roy-Barman, M Freydier, R van Beek, Pieter Souhaut, Marc Jeandel, C Influence of intense scavenging on Pa-Th fractionation in the wake of Kerguelen Island (Southern Ocean) |
topic_facet |
[SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography [CHIM.OTHE]Chemical Sciences/Other [CHIM.RADIO]Chemical Sciences/Radiochemistry |
description |
International audience Dissolved and particulate excess 230Th and 231Pa concentrations (noted 230Thxs and 231Paxs respectively) and 231Paxs/230Thxs activity ratios were investigated on and out of the Kerguelen plateau (Southern Ocean) in the framework of the Kerguelen Ocean and Plateau compared Study project in order to better understand the influence of particle flux and particle chemistry and advection on the scavenging of 231Pa.In the wake of Kerguelen, particulate 231Paxs is relatively abundant compared to its content in the dissolved phase. This, together with the low fractionation observed between 230Th and 231Pa (FTh/Pa ranging from 0.06 ± 0.01 to 1.6 ± 0.2) reflects the domination of the biogenic silica in the particle pool.Along the eastern escarpment of the Kerguelen plateau, the strong 231Paxs horizontal gradient in the deep waters highlights the intense removal of 231Pa at depth, as already observed for 230Thxs. This local boundary scavenging was attributed to re-suspension of opal-rich particles by nepheloid layers, resulting in fractionation factors FTh/Pa ≤ 1 along the Kerguelen plateau slope. Therefore, both the composition (biogenic opal) and the flux (intense along the margin) of particles control the scavenging of the two radionuclides in the Kerguelen wake.The modelling of 231Pa distribution with an advection-scavenging model demonstrates that lateral advection of open ocean water on the Kerguelen plateau could supply most of the 231Pa, which is then efficiently scavenged on the highly productive plateau, as previously proposed for 230Thxs. It stresses that lateral advection can play a significant role in the overall budget of particle reactive trace elements in a coastal-open ocean system. |
author2 |
Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS) Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP) Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS) Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE) Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)) Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA) Laboratoire des Mécanismes et Transfert en Géologie (LMTG) Université Toulouse III - Paul Sabatier (UT3) Université de Toulouse (UT)-Université de Toulouse (UT)-Observatoire Midi-Pyrénées (OMP) |
format |
Article in Journal/Newspaper |
author |
Venchiarutti, C Roy-Barman, M Freydier, R van Beek, Pieter Souhaut, Marc Jeandel, C |
author_facet |
Venchiarutti, C Roy-Barman, M Freydier, R van Beek, Pieter Souhaut, Marc Jeandel, C |
author_sort |
Venchiarutti, C |
title |
Influence of intense scavenging on Pa-Th fractionation in the wake of Kerguelen Island (Southern Ocean) |
title_short |
Influence of intense scavenging on Pa-Th fractionation in the wake of Kerguelen Island (Southern Ocean) |
title_full |
Influence of intense scavenging on Pa-Th fractionation in the wake of Kerguelen Island (Southern Ocean) |
title_fullStr |
Influence of intense scavenging on Pa-Th fractionation in the wake of Kerguelen Island (Southern Ocean) |
title_full_unstemmed |
Influence of intense scavenging on Pa-Th fractionation in the wake of Kerguelen Island (Southern Ocean) |
title_sort |
influence of intense scavenging on pa-th fractionation in the wake of kerguelen island (southern ocean) |
publisher |
HAL CCSD |
publishDate |
2011 |
url |
https://hal.science/hal-04511731 https://hal.science/hal-04511731/document https://hal.science/hal-04511731/file/Venchiarutti%20et%20al2011.pdf https://doi.org/10.5194/bg-8-3187-2011 |
genre |
Southern Ocean |
genre_facet |
Southern Ocean |
op_source |
ISSN: 1726-4170 EISSN: 1726-4189 Biogeosciences https://hal.science/hal-04511731 Biogeosciences, 2011, 8, pp.3187 - 3201. ⟨10.5194/bg-8-3187-2011⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.5194/bg-8-3187-2011 hal-04511731 https://hal.science/hal-04511731 https://hal.science/hal-04511731/document https://hal.science/hal-04511731/file/Venchiarutti%20et%20al2011.pdf doi:10.5194/bg-8-3187-2011 |
op_rights |
info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.5194/bg-8-3187-2011 |
container_title |
Biogeosciences |
container_volume |
8 |
container_issue |
11 |
container_start_page |
3187 |
op_container_end_page |
3201 |
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1810481468927901696 |
spelling |
ftceafr:oai:HAL:hal-04511731v1 2024-09-15T18:37:08+00:00 Influence of intense scavenging on Pa-Th fractionation in the wake of Kerguelen Island (Southern Ocean) Venchiarutti, C Roy-Barman, M Freydier, R van Beek, Pieter Souhaut, Marc Jeandel, C Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS) Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP) Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS) Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE) Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)) Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA) Laboratoire des Mécanismes et Transfert en Géologie (LMTG) Université Toulouse III - Paul Sabatier (UT3) Université de Toulouse (UT)-Université de Toulouse (UT)-Observatoire Midi-Pyrénées (OMP) 2011 https://hal.science/hal-04511731 https://hal.science/hal-04511731/document https://hal.science/hal-04511731/file/Venchiarutti%20et%20al2011.pdf https://doi.org/10.5194/bg-8-3187-2011 en eng HAL CCSD European Geosciences Union info:eu-repo/semantics/altIdentifier/doi/10.5194/bg-8-3187-2011 hal-04511731 https://hal.science/hal-04511731 https://hal.science/hal-04511731/document https://hal.science/hal-04511731/file/Venchiarutti%20et%20al2011.pdf doi:10.5194/bg-8-3187-2011 info:eu-repo/semantics/OpenAccess ISSN: 1726-4170 EISSN: 1726-4189 Biogeosciences https://hal.science/hal-04511731 Biogeosciences, 2011, 8, pp.3187 - 3201. ⟨10.5194/bg-8-3187-2011⟩ [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography [CHIM.OTHE]Chemical Sciences/Other [CHIM.RADIO]Chemical Sciences/Radiochemistry info:eu-repo/semantics/article Journal articles 2011 ftceafr https://doi.org/10.5194/bg-8-3187-2011 2024-07-22T12:59:53Z International audience Dissolved and particulate excess 230Th and 231Pa concentrations (noted 230Thxs and 231Paxs respectively) and 231Paxs/230Thxs activity ratios were investigated on and out of the Kerguelen plateau (Southern Ocean) in the framework of the Kerguelen Ocean and Plateau compared Study project in order to better understand the influence of particle flux and particle chemistry and advection on the scavenging of 231Pa.In the wake of Kerguelen, particulate 231Paxs is relatively abundant compared to its content in the dissolved phase. This, together with the low fractionation observed between 230Th and 231Pa (FTh/Pa ranging from 0.06 ± 0.01 to 1.6 ± 0.2) reflects the domination of the biogenic silica in the particle pool.Along the eastern escarpment of the Kerguelen plateau, the strong 231Paxs horizontal gradient in the deep waters highlights the intense removal of 231Pa at depth, as already observed for 230Thxs. This local boundary scavenging was attributed to re-suspension of opal-rich particles by nepheloid layers, resulting in fractionation factors FTh/Pa ≤ 1 along the Kerguelen plateau slope. Therefore, both the composition (biogenic opal) and the flux (intense along the margin) of particles control the scavenging of the two radionuclides in the Kerguelen wake.The modelling of 231Pa distribution with an advection-scavenging model demonstrates that lateral advection of open ocean water on the Kerguelen plateau could supply most of the 231Pa, which is then efficiently scavenged on the highly productive plateau, as previously proposed for 230Thxs. It stresses that lateral advection can play a significant role in the overall budget of particle reactive trace elements in a coastal-open ocean system. Article in Journal/Newspaper Southern Ocean HAL-CEA (Commissariat à l'énergie atomique et aux énergies alternatives) Biogeosciences 8 11 3187 3201 |