Hot and heterogenous high-he-3/He-4 components: New constraints from proto-Iceland plume lavas from Baffin Island
Author Posting. © American Geophysical Union, 2019. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geochemistry, Geophysics, Geosystems 20, (2019): 5939-5967, doi:10.1029/2019GC008654. The Icel...
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ftwhoas:oai:darchive.mblwhoilibrary.org:1912/25444 2023-05-15T15:35:23+02:00 Hot and heterogenous high-he-3/He-4 components: New constraints from proto-Iceland plume lavas from Baffin Island Willhite, Lori N. Jackson, Matthew G. Blichert-Toft, Janne Bindeman, Ilya N. Kurz, Mark D. Halldórsson, Saemundur Harðardóttir, Sunna Gazel, Esteban Price, Allison A. Byerly, Benjamin L. 2019-11-07 https://hdl.handle.net/1912/25444 unknown American Geophysical Union https://doi.org/10.1029/2019GC008654 Willhite, L. N., Jackson, M. G., Blichert-Toft, J., Bindeman, I., Kurz, M. D., Halldorsson, S. A., Hardardottir, S., Gazel, E., Price, A. A., & Byerly, B. L. (2019). Hot and heterogenous high-he-3/He-4 components: New constraints from proto-Iceland plume lavas from Baffin Island. Geochemistry Geophysics Geosystems, 20, 5939-5967. https://hdl.handle.net/1912/25444 doi:10.1029/2019GC008654 Willhite, L. N., Jackson, M. G., Blichert-Toft, J., Bindeman, I., Kurz, M. D., Halldorsson, S. A., Hardardottir, S., Gazel, E., Price, A. A., & Byerly, B. L. (2019). Hot and heterogenous high-he-3/He-4 components: New constraints from proto-Iceland plume lavas from Baffin Island. Geochemistry Geophysics Geosystems, 20, 5939-5967. doi:10.1029/2019GC008654 Article 2019 ftwhoas https://doi.org/10.1029/2019GC008654 2022-05-28T23:03:32Z Author Posting. © American Geophysical Union, 2019. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geochemistry, Geophysics, Geosystems 20, (2019): 5939-5967, doi:10.1029/2019GC008654. The Icelandic hotspot has erupted basaltic magma with the highest mantle‐derived 3He/4He 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 and Ce/Pb that fall within the mantle range (Nb/Th = 15.6 ± 2.6, Ce/Pb = 24.3 ± 4.3). These lavas have 87Sr/86Sr = 0.703008–0.703021, 143Nd/144Nd = 0.513094–0.513128, 176Hf/177Hf = 0.283265–0.283284, 206Pb/204Pb = 17.7560–17.9375, 3He/4He up to 39.9 RA, and mantle‐like δ18O of 5.03–5.21‰. The radiogenic isotopic compositions of the least crustally contaminated lavas are more geochemically depleted than Iceland high‐3He/4He 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‐3He/4He 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 mid‐ocean ridge basalts (1300 to 1410 °C), which attests to a hot, buoyant plume origin for early Iceland plume lavas. These observations support the contention that the geochemically heterogeneous high‐3He/4He domain is dense, located in ... Article in Journal/Newspaper Baffin Island Baffin Greenland Iceland Woods Hole Scientific Community: WHOAS (Woods Hole Open Access Server) Baffin Island Greenland Geochemistry, Geophysics, Geosystems 20 12 5939 5967 |
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Open Polar |
collection |
Woods Hole Scientific Community: WHOAS (Woods Hole Open Access Server) |
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ftwhoas |
language |
unknown |
description |
Author Posting. © American Geophysical Union, 2019. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geochemistry, Geophysics, Geosystems 20, (2019): 5939-5967, doi:10.1029/2019GC008654. The Icelandic hotspot has erupted basaltic magma with the highest mantle‐derived 3He/4He 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 and Ce/Pb that fall within the mantle range (Nb/Th = 15.6 ± 2.6, Ce/Pb = 24.3 ± 4.3). These lavas have 87Sr/86Sr = 0.703008–0.703021, 143Nd/144Nd = 0.513094–0.513128, 176Hf/177Hf = 0.283265–0.283284, 206Pb/204Pb = 17.7560–17.9375, 3He/4He up to 39.9 RA, and mantle‐like δ18O of 5.03–5.21‰. The radiogenic isotopic compositions of the least crustally contaminated lavas are more geochemically depleted than Iceland high‐3He/4He 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‐3He/4He 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 mid‐ocean ridge basalts (1300 to 1410 °C), which attests to a hot, buoyant plume origin for early Iceland plume lavas. These observations support the contention that the geochemically heterogeneous high‐3He/4He domain is dense, located in ... |
format |
Article in Journal/Newspaper |
author |
Willhite, Lori N. Jackson, Matthew G. Blichert-Toft, Janne Bindeman, Ilya N. Kurz, Mark D. Halldórsson, Saemundur Harðardóttir, Sunna Gazel, Esteban Price, Allison A. Byerly, Benjamin L. |
spellingShingle |
Willhite, Lori N. Jackson, Matthew G. Blichert-Toft, Janne Bindeman, Ilya N. Kurz, Mark D. Halldórsson, Saemundur Harðardóttir, Sunna Gazel, Esteban Price, Allison A. Byerly, Benjamin L. Hot and heterogenous high-he-3/He-4 components: New constraints from proto-Iceland plume lavas from Baffin Island |
author_facet |
Willhite, Lori N. Jackson, Matthew G. Blichert-Toft, Janne Bindeman, Ilya N. Kurz, Mark D. Halldórsson, Saemundur Harðardóttir, Sunna Gazel, Esteban Price, Allison A. Byerly, Benjamin L. |
author_sort |
Willhite, Lori N. |
title |
Hot and heterogenous high-he-3/He-4 components: New constraints from proto-Iceland plume lavas from Baffin Island |
title_short |
Hot and heterogenous high-he-3/He-4 components: New constraints from proto-Iceland plume lavas from Baffin Island |
title_full |
Hot and heterogenous high-he-3/He-4 components: New constraints from proto-Iceland plume lavas from Baffin Island |
title_fullStr |
Hot and heterogenous high-he-3/He-4 components: New constraints from proto-Iceland plume lavas from Baffin Island |
title_full_unstemmed |
Hot and heterogenous high-he-3/He-4 components: New constraints from proto-Iceland plume lavas from Baffin Island |
title_sort |
hot and heterogenous high-he-3/he-4 components: new constraints from proto-iceland plume lavas from baffin island |
publisher |
American Geophysical Union |
publishDate |
2019 |
url |
https://hdl.handle.net/1912/25444 |
geographic |
Baffin Island Greenland |
geographic_facet |
Baffin Island Greenland |
genre |
Baffin Island Baffin Greenland Iceland |
genre_facet |
Baffin Island Baffin Greenland Iceland |
op_source |
Willhite, L. N., Jackson, M. G., Blichert-Toft, J., Bindeman, I., Kurz, M. D., Halldorsson, S. A., Hardardottir, S., Gazel, E., Price, A. A., & Byerly, B. L. (2019). Hot and heterogenous high-he-3/He-4 components: New constraints from proto-Iceland plume lavas from Baffin Island. Geochemistry Geophysics Geosystems, 20, 5939-5967. doi:10.1029/2019GC008654 |
op_relation |
https://doi.org/10.1029/2019GC008654 Willhite, L. N., Jackson, M. G., Blichert-Toft, J., Bindeman, I., Kurz, M. D., Halldorsson, S. A., Hardardottir, S., Gazel, E., Price, A. A., & Byerly, B. L. (2019). Hot and heterogenous high-he-3/He-4 components: New constraints from proto-Iceland plume lavas from Baffin Island. Geochemistry Geophysics Geosystems, 20, 5939-5967. https://hdl.handle.net/1912/25444 doi:10.1029/2019GC008654 |
op_doi |
https://doi.org/10.1029/2019GC008654 |
container_title |
Geochemistry, Geophysics, Geosystems |
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20 |
container_issue |
12 |
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5939 |
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5967 |
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