Restoration of the North-east Atlantic and Mediterranean Sea hydrology from the neodymium isotopes since the last glacial period
: The purpose of this thesis is to constrain the hydrology of the North-East Atlantic and western Mediterranean Sea since the last glacial period from neodymium isotopic composition (εNd) measured on seawater, cold water corals and foraminifera. In particular, hydrological changes of intermediate wa...
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Format: | Doctoral or Postdoctoral Thesis |
Language: | French |
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2016
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Online Access: | https://theses.hal.science/tel-01404733 https://theses.hal.science/tel-01404733/document https://theses.hal.science/tel-01404733/file/78158_DUBOIS-DAUPHIN_2016_diffusion.pdf |
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ftuniparissaclay:oai:HAL:tel-01404733v1 2024-06-16T07:39:36+00:00 Restoration of the North-east Atlantic and Mediterranean Sea hydrology from the neodymium isotopes since the last glacial period Restitution de l’hydrologie de l’Atlantique Nord-Est et de la Méditerranée occidentale depuis la dernière période glaciaire à partir de la composition isotopique du néodyme mesurée dans l’eau de mer et les coraux d’eau froide Dubois-Dauphin, Quentin Géosciences Paris Sud (GEOPS) Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS) Université Paris Saclay (COmUE) Christophe Colin 2016-06-03 https://theses.hal.science/tel-01404733 https://theses.hal.science/tel-01404733/document https://theses.hal.science/tel-01404733/file/78158_DUBOIS-DAUPHIN_2016_diffusion.pdf fr fre HAL CCSD NNT: 2016SACLS114 tel-01404733 https://theses.hal.science/tel-01404733 https://theses.hal.science/tel-01404733/document https://theses.hal.science/tel-01404733/file/78158_DUBOIS-DAUPHIN_2016_diffusion.pdf info:eu-repo/semantics/OpenAccess https://theses.hal.science/tel-01404733 Climatologie. Université Paris Saclay (COmUE), 2016. Français. ⟨NNT : 2016SACLS114⟩ Neodymium isotopes Cold-Water corals Mediterranean Sea North-East Astlantic Composition isotopique du Nd Coraux d'eau froide Atlantique nord Mer Mediterranée [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography info:eu-repo/semantics/doctoralThesis Theses 2016 ftuniparissaclay 2024-05-17T00:13:48Z : The purpose of this thesis is to constrain the hydrology of the North-East Atlantic and western Mediterranean Sea since the last glacial period from neodymium isotopic composition (εNd) measured on seawater, cold water corals and foraminifera. In particular, hydrological changes of intermediate water masses (LIW, AAIW, MSW, mid-subtropical and subpolar gyre water) have been studied as their role on salt budget in North Atlantic and ultimately on AMOC are currently poorly constrained. This work has been conducted at times of major and abrupt hydrological changes that occurred during rapid climatic variations of the last glacial period (Heinrich and Dansgaard-Oeschger events) and during the last sapropel deposit (S1) in eastern Mediterranean Sea. In a first step, we have improved the spatial distribution of water masses εNd values in North-east Atlantic and Alboran Sea, what is an absolute prerequisite in order to track past hydrological changes in these areas with εNd proxy. Next, we have highlighted a major change of the western Mediterranean circulation pattern during the sapropel S1 deposit, which is marked south of Sardinia by a strong reduction of eastern-sourced water masses (LIW) in favor of western-sourced water masses (WIW). This hydrological change as well as those occurring in Mediterranean Sea since the last glacial period was not associated with strong modifications of εNd values in Alboran and Balearic Sea, suggesting a stability of Nd isotopic signature of MOW over the time. This has highlighted, from an εNd record obtained on cold water corals in the Gulf of Cadiz, an enhanced contribution of more radiogenic AAIW and therefore a stronger northward penetration in North Atlantic at times of reduced AMOC linked to iceberg discharges from Northern Hemisphere ice sheets. L’objectif de cette thèse est d’apporter de nouvelles contraintes sur l’hydrologie de l’Atlantique Nord-Est et de la Méditerranée occidentale depuis la dernière période glaciaire à partir de l’analyse de la composition isotopique ... Doctoral or Postdoctoral Thesis Dansgaard-Oeschger events North Atlantic North East Atlantic Archives ouvertes de Paris-Saclay |
institution |
Open Polar |
collection |
Archives ouvertes de Paris-Saclay |
op_collection_id |
ftuniparissaclay |
language |
French |
topic |
Neodymium isotopes Cold-Water corals Mediterranean Sea North-East Astlantic Composition isotopique du Nd Coraux d'eau froide Atlantique nord Mer Mediterranée [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography |
spellingShingle |
Neodymium isotopes Cold-Water corals Mediterranean Sea North-East Astlantic Composition isotopique du Nd Coraux d'eau froide Atlantique nord Mer Mediterranée [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography Dubois-Dauphin, Quentin Restoration of the North-east Atlantic and Mediterranean Sea hydrology from the neodymium isotopes since the last glacial period |
topic_facet |
Neodymium isotopes Cold-Water corals Mediterranean Sea North-East Astlantic Composition isotopique du Nd Coraux d'eau froide Atlantique nord Mer Mediterranée [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography |
description |
: The purpose of this thesis is to constrain the hydrology of the North-East Atlantic and western Mediterranean Sea since the last glacial period from neodymium isotopic composition (εNd) measured on seawater, cold water corals and foraminifera. In particular, hydrological changes of intermediate water masses (LIW, AAIW, MSW, mid-subtropical and subpolar gyre water) have been studied as their role on salt budget in North Atlantic and ultimately on AMOC are currently poorly constrained. This work has been conducted at times of major and abrupt hydrological changes that occurred during rapid climatic variations of the last glacial period (Heinrich and Dansgaard-Oeschger events) and during the last sapropel deposit (S1) in eastern Mediterranean Sea. In a first step, we have improved the spatial distribution of water masses εNd values in North-east Atlantic and Alboran Sea, what is an absolute prerequisite in order to track past hydrological changes in these areas with εNd proxy. Next, we have highlighted a major change of the western Mediterranean circulation pattern during the sapropel S1 deposit, which is marked south of Sardinia by a strong reduction of eastern-sourced water masses (LIW) in favor of western-sourced water masses (WIW). This hydrological change as well as those occurring in Mediterranean Sea since the last glacial period was not associated with strong modifications of εNd values in Alboran and Balearic Sea, suggesting a stability of Nd isotopic signature of MOW over the time. This has highlighted, from an εNd record obtained on cold water corals in the Gulf of Cadiz, an enhanced contribution of more radiogenic AAIW and therefore a stronger northward penetration in North Atlantic at times of reduced AMOC linked to iceberg discharges from Northern Hemisphere ice sheets. L’objectif de cette thèse est d’apporter de nouvelles contraintes sur l’hydrologie de l’Atlantique Nord-Est et de la Méditerranée occidentale depuis la dernière période glaciaire à partir de l’analyse de la composition isotopique ... |
author2 |
Géosciences Paris Sud (GEOPS) Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS) Université Paris Saclay (COmUE) Christophe Colin |
format |
Doctoral or Postdoctoral Thesis |
author |
Dubois-Dauphin, Quentin |
author_facet |
Dubois-Dauphin, Quentin |
author_sort |
Dubois-Dauphin, Quentin |
title |
Restoration of the North-east Atlantic and Mediterranean Sea hydrology from the neodymium isotopes since the last glacial period |
title_short |
Restoration of the North-east Atlantic and Mediterranean Sea hydrology from the neodymium isotopes since the last glacial period |
title_full |
Restoration of the North-east Atlantic and Mediterranean Sea hydrology from the neodymium isotopes since the last glacial period |
title_fullStr |
Restoration of the North-east Atlantic and Mediterranean Sea hydrology from the neodymium isotopes since the last glacial period |
title_full_unstemmed |
Restoration of the North-east Atlantic and Mediterranean Sea hydrology from the neodymium isotopes since the last glacial period |
title_sort |
restoration of the north-east atlantic and mediterranean sea hydrology from the neodymium isotopes since the last glacial period |
publisher |
HAL CCSD |
publishDate |
2016 |
url |
https://theses.hal.science/tel-01404733 https://theses.hal.science/tel-01404733/document https://theses.hal.science/tel-01404733/file/78158_DUBOIS-DAUPHIN_2016_diffusion.pdf |
genre |
Dansgaard-Oeschger events North Atlantic North East Atlantic |
genre_facet |
Dansgaard-Oeschger events North Atlantic North East Atlantic |
op_source |
https://theses.hal.science/tel-01404733 Climatologie. Université Paris Saclay (COmUE), 2016. Français. ⟨NNT : 2016SACLS114⟩ |
op_relation |
NNT: 2016SACLS114 tel-01404733 https://theses.hal.science/tel-01404733 https://theses.hal.science/tel-01404733/document https://theses.hal.science/tel-01404733/file/78158_DUBOIS-DAUPHIN_2016_diffusion.pdf |
op_rights |
info:eu-repo/semantics/OpenAccess |
_version_ |
1802006354583355392 |