Hot and heterogenous high-3 He/ 4 He components: New constraints from proto- Iceland plume lavas from Baffin Island
International audience Key Points: • Baffin Island-West Greenland high-3 He/ 4 He lavas are more geochemically depleted than any other high-3 He/ 4 He lavas globally. • The isotopic composition of the high-3 He/ 4 He mantle source in the Iceland plume has evolved through time. • Baffin Island and We...
Published in: | Geochemistry, Geophysics, Geosystems |
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Online Access: | https://hal.science/hal-02995379 https://hal.science/hal-02995379/document https://hal.science/hal-02995379/file/Willhite%20et%20al%202019%20revised%20manuscript%20G-Cubed.pdf https://doi.org/10.1029/2019GC008654 |
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ftunivstetienne:oai:HAL:hal-02995379v1 2024-09-15T17:57:02+00:00 Hot and heterogenous high-3 He/ 4 He components: New constraints from proto- Iceland plume lavas from Baffin Island Willhite, Lori, N Jackson, Matthew, G Blichert-Toft, Janne Bindeman, Ilya Kurz, Mark, D Halldórsson, Saemundur, A Harðardóttir, Sunna Gazel, Esteban Price, Allison, A Byerly, Benjamin, L University of California Santa Barbara (UC Santa Barbara) University of California (UC) Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE) École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL) Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS) 2019 https://hal.science/hal-02995379 https://hal.science/hal-02995379/document https://hal.science/hal-02995379/file/Willhite%20et%20al%202019%20revised%20manuscript%20G-Cubed.pdf https://doi.org/10.1029/2019GC008654 en eng HAL CCSD AGU and the Geochemical Society info:eu-repo/semantics/altIdentifier/doi/10.1029/2019GC008654 hal-02995379 https://hal.science/hal-02995379 https://hal.science/hal-02995379/document https://hal.science/hal-02995379/file/Willhite%20et%20al%202019%20revised%20manuscript%20G-Cubed.pdf doi:10.1029/2019GC008654 info:eu-repo/semantics/OpenAccess EISSN: 1525-2027 Geochemistry, Geophysics, Geosystems https://hal.science/hal-02995379 Geochemistry, Geophysics, Geosystems, 2019, ⟨10.1029/2019GC008654⟩ [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry info:eu-repo/semantics/article Journal articles 2019 ftunivstetienne https://doi.org/10.1029/2019GC008654 2024-07-22T23:40:58Z International audience Key Points: • Baffin Island-West Greenland high-3 He/ 4 He lavas are more geochemically depleted than any other high-3 He/ 4 He lavas globally. • The isotopic composition of the high-3 He/ 4 He mantle source in the Iceland plume has evolved through time. • Baffin Island and West Greenland primary melts record hotter temperatures than high-MgO MORB, consistent with a deep, dense plume source. Abstract The Icelandic hotspot has erupted basaltic magma with the highest mantle-derived 3 He/ 4 He over a period spanning much of the Cenozoic, from the early-Cenozoic Baffin Island-West Greenland flood basalt province (49.8 RA), to mid-Miocene lavas in northwest Iceland (40.2 to 47.5 RA), to Pleistocene lavas in Iceland's neovolcanic zone (34.3 RA). The Baffin Island lavas transited through and potentially assimilated variable amounts of Precambrian continental basement. We use geochemical indicators sensitive to continental crust assimilation (Nb/Th, Ce/Pb, MgO) to identify the least crustally contaminated lavas. Four lavas, identified as "least crustally contaminated", have high MgO (>15 wt.%), and Nb/Th, Ce/Pb that fall within the mantle range (Nb/Th=15.6±2.6, Ce/Pb=24.3±4.3). These lavas have 87 Sr/ 86 Sr = 0.703008-0.703021, 143 Nd/ 144 Nd = 0.513094-0.513128, 176 Hf/ 177 Hf = 0.283265-0.283284, 206 Pb/ 204 Pb = 17.7560-17.9375, 3 He/ 4 He up to 39.9 RA, and mantle-like δ 18 O of 5.03-5.21‰. The radiogenic isotopic compositions of the least crustally contaminated lavas are more geochemically depleted than Iceland high-3 He/ 4 He lavas, a shift that cannot be explained by continental crust assimilation in the Baffin suite. Thus, we argue for the presence of two geochemically distinct high-3 He/ 4 He components within the Iceland plume. Additionally, the least crustally contaminated primary melts from Baffin Island-West Greenland have higher mantle potential temperatures (1510 to 1630 °C) than Siqueiros MORB (1300 to 1410 °C), which attests to a hot, buoyant plume origin for early Iceland ... Article in Journal/Newspaper Baffin Island Baffin Greenland Iceland Université Jean Monnet – Saint-Etienne: HAL Geochemistry, Geophysics, Geosystems 20 12 5939 5967 |
institution |
Open Polar |
collection |
Université Jean Monnet – Saint-Etienne: HAL |
op_collection_id |
ftunivstetienne |
language |
English |
topic |
[SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry |
spellingShingle |
[SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry Willhite, Lori, N Jackson, Matthew, G Blichert-Toft, Janne Bindeman, Ilya Kurz, Mark, D Halldórsson, Saemundur, A Harðardóttir, Sunna Gazel, Esteban Price, Allison, A Byerly, Benjamin, L Hot and heterogenous high-3 He/ 4 He components: New constraints from proto- Iceland plume lavas from Baffin Island |
topic_facet |
[SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry |
description |
International audience Key Points: • Baffin Island-West Greenland high-3 He/ 4 He lavas are more geochemically depleted than any other high-3 He/ 4 He lavas globally. • The isotopic composition of the high-3 He/ 4 He mantle source in the Iceland plume has evolved through time. • Baffin Island and West Greenland primary melts record hotter temperatures than high-MgO MORB, consistent with a deep, dense plume source. Abstract The Icelandic hotspot has erupted basaltic magma with the highest mantle-derived 3 He/ 4 He over a period spanning much of the Cenozoic, from the early-Cenozoic Baffin Island-West Greenland flood basalt province (49.8 RA), to mid-Miocene lavas in northwest Iceland (40.2 to 47.5 RA), to Pleistocene lavas in Iceland's neovolcanic zone (34.3 RA). The Baffin Island lavas transited through and potentially assimilated variable amounts of Precambrian continental basement. We use geochemical indicators sensitive to continental crust assimilation (Nb/Th, Ce/Pb, MgO) to identify the least crustally contaminated lavas. Four lavas, identified as "least crustally contaminated", have high MgO (>15 wt.%), and Nb/Th, Ce/Pb that fall within the mantle range (Nb/Th=15.6±2.6, Ce/Pb=24.3±4.3). These lavas have 87 Sr/ 86 Sr = 0.703008-0.703021, 143 Nd/ 144 Nd = 0.513094-0.513128, 176 Hf/ 177 Hf = 0.283265-0.283284, 206 Pb/ 204 Pb = 17.7560-17.9375, 3 He/ 4 He up to 39.9 RA, and mantle-like δ 18 O of 5.03-5.21‰. The radiogenic isotopic compositions of the least crustally contaminated lavas are more geochemically depleted than Iceland high-3 He/ 4 He lavas, a shift that cannot be explained by continental crust assimilation in the Baffin suite. Thus, we argue for the presence of two geochemically distinct high-3 He/ 4 He components within the Iceland plume. Additionally, the least crustally contaminated primary melts from Baffin Island-West Greenland have higher mantle potential temperatures (1510 to 1630 °C) than Siqueiros MORB (1300 to 1410 °C), which attests to a hot, buoyant plume origin for early Iceland ... |
author2 |
University of California Santa Barbara (UC Santa Barbara) University of California (UC) Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE) École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL) Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS) |
format |
Article in Journal/Newspaper |
author |
Willhite, Lori, N Jackson, Matthew, G Blichert-Toft, Janne Bindeman, Ilya Kurz, Mark, D Halldórsson, Saemundur, A Harðardóttir, Sunna Gazel, Esteban Price, Allison, A Byerly, Benjamin, L |
author_facet |
Willhite, Lori, N Jackson, Matthew, G Blichert-Toft, Janne Bindeman, Ilya Kurz, Mark, D Halldórsson, Saemundur, A Harðardóttir, Sunna Gazel, Esteban Price, Allison, A Byerly, Benjamin, L |
author_sort |
Willhite, Lori, N |
title |
Hot and heterogenous high-3 He/ 4 He components: New constraints from proto- Iceland plume lavas from Baffin Island |
title_short |
Hot and heterogenous high-3 He/ 4 He components: New constraints from proto- Iceland plume lavas from Baffin Island |
title_full |
Hot and heterogenous high-3 He/ 4 He components: New constraints from proto- Iceland plume lavas from Baffin Island |
title_fullStr |
Hot and heterogenous high-3 He/ 4 He components: New constraints from proto- Iceland plume lavas from Baffin Island |
title_full_unstemmed |
Hot and heterogenous high-3 He/ 4 He components: New constraints from proto- Iceland plume lavas from Baffin Island |
title_sort |
hot and heterogenous high-3 he/ 4 he components: new constraints from proto- iceland plume lavas from baffin island |
publisher |
HAL CCSD |
publishDate |
2019 |
url |
https://hal.science/hal-02995379 https://hal.science/hal-02995379/document https://hal.science/hal-02995379/file/Willhite%20et%20al%202019%20revised%20manuscript%20G-Cubed.pdf https://doi.org/10.1029/2019GC008654 |
genre |
Baffin Island Baffin Greenland Iceland |
genre_facet |
Baffin Island Baffin Greenland Iceland |
op_source |
EISSN: 1525-2027 Geochemistry, Geophysics, Geosystems https://hal.science/hal-02995379 Geochemistry, Geophysics, Geosystems, 2019, ⟨10.1029/2019GC008654⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1029/2019GC008654 hal-02995379 https://hal.science/hal-02995379 https://hal.science/hal-02995379/document https://hal.science/hal-02995379/file/Willhite%20et%20al%202019%20revised%20manuscript%20G-Cubed.pdf doi:10.1029/2019GC008654 |
op_rights |
info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.1029/2019GC008654 |
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Geochemistry, Geophysics, Geosystems |
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20 |
container_issue |
12 |
container_start_page |
5939 |
op_container_end_page |
5967 |
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1810433237104721920 |