| Registro completo |
| Provedor de dados: |
ArchiMer
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| País: |
France
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| Título: |
The isotopic (He, Ne, Sr, Nd, Hf, Pb) signature in the Indian Mantle over 8.8 Ma
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| Autores: |
Paquet, Marine
Hamelin, Cédric
Moreira, Manuel
Cannat, Mathilde
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| Data: |
2020-09
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| Ano: |
2020
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| Palavras-chave: |
Mid-Ocean Ridge Basalts
Mantle heterogeneity
Noble gases
Isotope geochemistry
Melt/mantle interactions
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| Resumo: |
The eastern Southwest Indian Ridge, between 61° and 67°E, has a very low melt supply and comprises several corridors of nearly amagmatic spreading that expose mantle-derived serpentinized peridotite. More volcanically active ridge portions separate these corridors. He, Ne, Pb, Nd, Hf and Sr isotopes were analyzed in basalt glasses dredged on two types of seafloor: volcanic and ultramafic. Basalts dredged in ultramafic seafloor on-axis tend to be slightly more depleted for heavy radiogenic isotopes and show slightly higher 3He/4He isotope ratios than basalts dredged in volcanic seafloor, with no systematic difference in neon isotope ratios. We propose that both types of basalts are derived from the same mantle source, but that the basalts dredged on ultramafic seafloor are more affected by melt/mantle reactions, which slightly modify their isotopic signatures. Our dataset also includes a few basalts, dredged on off-axis ultramafic seafloor, that range in age between 2.6 and 8.8 Ma. These few and widely-spaced off-axis samples, erupted at the ridge axis, are a rare opportunity to capture the potential geochemical variability of the mantle source in an ultramafic seafloor corridor over 8.8 Ma. This temporal variability appears to be minor compared to the overall range of isotopic variability of the on-axis lavas from the 61°-67°E region.
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| Tipo: |
Text
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| Idioma: |
Inglês
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| Identificador: |
https://archimer.ifremer.fr/doc/00633/74525/74360.jpg
https://archimer.ifremer.fr/doc/00633/74525/74361.xlsx
https://archimer.ifremer.fr/doc/00633/74525/74362.xlsx
https://archimer.ifremer.fr/doc/00633/74525/74492.pdf
DOI:10.1016/j.chemgeo.2020.119741
https://archimer.ifremer.fr/doc/00633/74525/
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| Editor: |
Elsevier BV
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| Formato: |
application/pdf
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| Fonte: |
Chemical Geology (0009-2541) (Elsevier BV), 2020-09 , Vol. 550 , P. 119741 (12p.)
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| Direitos: |
info:eu-repo/semantics/openAccess
restricted use
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