Shallow level interactions and geochemistry of oceanic island basalt : implications on the acquisition of the isotopic fingerprints and on mantle topology
Systematic measurements of Sr-Nd-Pb isotopic compositions in Oceanic Island Basalts (OIB) for 30 years have shown the complex nature of mantle sources. However, measured variations in these samples can be related either to variable proportions of the components present in the deep source of the basa...
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fttriple:oai:gotriple.eu:10670/1.hhvp70 2023-05-15T16:57:09+02:00 Shallow level interactions and geochemistry of oceanic island basalt : implications on the acquisition of the isotopic fingerprints and on mantle topology Interactions de faibles profondeurs et géochimie des basaltes d'îles océaniques : implications sur les modes d'acquisition de la signature isotopique et sur la topogique mantellique Millet, Marc-Alban Laboratoire Magmas et Volcans (LMV) Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet Saint-Étienne (UJM)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC) Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS) Université Blaise Pascal - Clermont-Ferrand II Pierre Schiano 2007-11-27 https://tel.archives-ouvertes.fr/tel-00718419/file/2007CLF21794.pdf https://tel.archives-ouvertes.fr/tel-00718419 fr fre HAL CCSD NNT: 2007CLF21794 tel-00718419 10670/1.hhvp70 https://tel.archives-ouvertes.fr/tel-00718419/file/2007CLF21794.pdf https://tel.archives-ouvertes.fr/tel-00718419 other Le serveur TEL (thèses-en-ligne) Volcanologie. Université Blaise Pascal - Clermont-Ferrand II, 2007. Français. ⟨NNT : 2007CLF21794⟩ mantle plume shallow-level interactions Azores Cape Verde endmember common component OIB isotope panache mantellique Interactions de faibles profondeurs Açores Cap Vert pôle de mélange composant commun geo envir Thesis https://vocabularies.coar-repositories.org/resource_types/c_46ec/ 2007 fttriple 2023-01-22T17:24:44Z Systematic measurements of Sr-Nd-Pb isotopic compositions in Oceanic Island Basalts (OIB) for 30 years have shown the complex nature of mantle sources. However, measured variations in these samples can be related either to variable proportions of the components present in the deep source of the basalts, or to interactions between the pristine melts and the environments encountered during their ascent to the surface during partial melting, plume-lithosphere interaction, assimilation and fractional crystallization or post-eruption seawater interaction processes. Therefore, extracting the signature of shallow-level interactions from the global geochemical signature is a key to retrieving the source information and to investigating mantle topology in greater details. Means to identify and see through these shallow-level interactions are first presented before being applied to 2 case studies done on 2 islands in different geodynamic setting (São Nicolau Island, Cape Verde archipelago, intraplate setting and old lithosphere; São Jorge Island, Azores archipelago, Plume-ridge interaction setting on a young lithosphere). Major and trace elements as well as Sr-Nd-Pb isotopes measurements show that an important part of the isotopic variations can be explained by shallow-level interactions rather than source heterogeneity. These results are extended from the island-scale to the archipelago-scale in both cases. Identification of such processes in locality playing a key role in the definition of mantle topology allows generalizing the conclusions of the 2 local studies to a global scale. On this basis, the existence and nature of a sub-primitive component common to all OIB (FOZO, PHEM, C), inferred from non-filtered OIB data compilation, is then discussed. Les compositions isotopiques de Sr, Nd et Pb des basaltes d'îles océaniques ont été mesurées de manière systématique depuis 30 ans. Les variations de ces compositions sont classiquement interprétées comme la signature du mélange entre des composants présents au sein des ... Thesis Jorge Island Unknown Jorge Island ENVELOPE(-59.767,-59.767,-62.383,-62.383) |
institution |
Open Polar |
collection |
Unknown |
op_collection_id |
fttriple |
language |
French |
topic |
mantle plume shallow-level interactions Azores Cape Verde endmember common component OIB isotope panache mantellique Interactions de faibles profondeurs Açores Cap Vert pôle de mélange composant commun geo envir |
spellingShingle |
mantle plume shallow-level interactions Azores Cape Verde endmember common component OIB isotope panache mantellique Interactions de faibles profondeurs Açores Cap Vert pôle de mélange composant commun geo envir Millet, Marc-Alban Shallow level interactions and geochemistry of oceanic island basalt : implications on the acquisition of the isotopic fingerprints and on mantle topology |
topic_facet |
mantle plume shallow-level interactions Azores Cape Verde endmember common component OIB isotope panache mantellique Interactions de faibles profondeurs Açores Cap Vert pôle de mélange composant commun geo envir |
description |
Systematic measurements of Sr-Nd-Pb isotopic compositions in Oceanic Island Basalts (OIB) for 30 years have shown the complex nature of mantle sources. However, measured variations in these samples can be related either to variable proportions of the components present in the deep source of the basalts, or to interactions between the pristine melts and the environments encountered during their ascent to the surface during partial melting, plume-lithosphere interaction, assimilation and fractional crystallization or post-eruption seawater interaction processes. Therefore, extracting the signature of shallow-level interactions from the global geochemical signature is a key to retrieving the source information and to investigating mantle topology in greater details. Means to identify and see through these shallow-level interactions are first presented before being applied to 2 case studies done on 2 islands in different geodynamic setting (São Nicolau Island, Cape Verde archipelago, intraplate setting and old lithosphere; São Jorge Island, Azores archipelago, Plume-ridge interaction setting on a young lithosphere). Major and trace elements as well as Sr-Nd-Pb isotopes measurements show that an important part of the isotopic variations can be explained by shallow-level interactions rather than source heterogeneity. These results are extended from the island-scale to the archipelago-scale in both cases. Identification of such processes in locality playing a key role in the definition of mantle topology allows generalizing the conclusions of the 2 local studies to a global scale. On this basis, the existence and nature of a sub-primitive component common to all OIB (FOZO, PHEM, C), inferred from non-filtered OIB data compilation, is then discussed. Les compositions isotopiques de Sr, Nd et Pb des basaltes d'îles océaniques ont été mesurées de manière systématique depuis 30 ans. Les variations de ces compositions sont classiquement interprétées comme la signature du mélange entre des composants présents au sein des ... |
author2 |
Laboratoire Magmas et Volcans (LMV) Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet Saint-Étienne (UJM)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC) Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS) Université Blaise Pascal - Clermont-Ferrand II Pierre Schiano |
format |
Thesis |
author |
Millet, Marc-Alban |
author_facet |
Millet, Marc-Alban |
author_sort |
Millet, Marc-Alban |
title |
Shallow level interactions and geochemistry of oceanic island basalt : implications on the acquisition of the isotopic fingerprints and on mantle topology |
title_short |
Shallow level interactions and geochemistry of oceanic island basalt : implications on the acquisition of the isotopic fingerprints and on mantle topology |
title_full |
Shallow level interactions and geochemistry of oceanic island basalt : implications on the acquisition of the isotopic fingerprints and on mantle topology |
title_fullStr |
Shallow level interactions and geochemistry of oceanic island basalt : implications on the acquisition of the isotopic fingerprints and on mantle topology |
title_full_unstemmed |
Shallow level interactions and geochemistry of oceanic island basalt : implications on the acquisition of the isotopic fingerprints and on mantle topology |
title_sort |
shallow level interactions and geochemistry of oceanic island basalt : implications on the acquisition of the isotopic fingerprints and on mantle topology |
publisher |
HAL CCSD |
publishDate |
2007 |
url |
https://tel.archives-ouvertes.fr/tel-00718419/file/2007CLF21794.pdf https://tel.archives-ouvertes.fr/tel-00718419 |
long_lat |
ENVELOPE(-59.767,-59.767,-62.383,-62.383) |
geographic |
Jorge Island |
geographic_facet |
Jorge Island |
genre |
Jorge Island |
genre_facet |
Jorge Island |
op_source |
Le serveur TEL (thèses-en-ligne) Volcanologie. Université Blaise Pascal - Clermont-Ferrand II, 2007. Français. ⟨NNT : 2007CLF21794⟩ |
op_relation |
NNT: 2007CLF21794 tel-00718419 10670/1.hhvp70 https://tel.archives-ouvertes.fr/tel-00718419/file/2007CLF21794.pdf https://tel.archives-ouvertes.fr/tel-00718419 |
op_rights |
other |
_version_ |
1766048418131607552 |