Primordial neon in high-³He/â´He Baffin Island olivines
Paleocene basaltic lavas exposed on Baffin Island have the highest ³He/â´He found in any terrestrial igneous rocks and potentially contain the most pristine primordial mantle material exposed on Earth's surface. By vacuum-crushing large (1–3 g) olivine mineral separates, we extracted enough...
Published in: | Earth and Planetary Science Letters |
---|---|
Main Authors: | , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | unknown |
Published: |
Elsevier
2021
|
Subjects: | |
Online Access: | https://doi.org/10.1016/j.epsl.2021.116762 |
id |
ftcaltechauth:oai:authors.library.caltech.edu:bmk75-a5e89 |
---|---|
record_format |
openpolar |
spelling |
ftcaltechauth:oai:authors.library.caltech.edu:bmk75-a5e89 2024-06-23T07:51:29+00:00 Primordial neon in high-³He/â´He Baffin Island olivines Horton, F. Curtice, J. Farley, K. A. Kurz, M. D. Asimow, P. D. Treffkorn, J. Boyes, X. M. 2021-03-15 https://doi.org/10.1016/j.epsl.2021.116762 unknown Elsevier https://doi.org/10.1016/j.epsl.2021.116762 oai:authors.library.caltech.edu:bmk75-a5e89 eprintid:108479 resolverid:CaltechAUTHORS:20210318-103515860 info:eu-repo/semantics/closedAccess Other Earth and Planetary Science Letters, 558, Art. No. 116762, (2021-03-15) primordial mantle hotspot lavas neon isotopes noble gas geochemistry info:eu-repo/semantics/article 2021 ftcaltechauth https://doi.org/10.1016/j.epsl.2021.116762 2024-06-12T06:06:00Z Paleocene basaltic lavas exposed on Baffin Island have the highest ³He/â´He found in any terrestrial igneous rocks and potentially contain the most pristine primordial mantle material exposed on Earth's surface. By vacuum-crushing large (1–3 g) olivine mineral separates, we extracted enough magmatic gas to obtain the first coupled helium, neon, and argon isotopic compositions of Baffin Island lavas. The five Baffin Island olivine samples have ³He/â´He ranging from 36.2 ± 0.6 to 48.6 ± 1.3 (1σ) times the atmospheric ratio (Ra), overlapping with the highest known mantle values. Neon isotopic results fall on a mixing line between atmosphere and a high ²â°Ne/²²Ne mantle endmember (with a maximum ²â°Ne/²²Ne of 12.2). The slope of this mixing line is indistinguishable from that in subglacial Holocene glass from Iceland, but distinct from other hotspots and mid-ocean ridge basalt trends. This result supports the hypothesis that Baffin Island and Iceland lavas share a common high-³He/â´He mantle component, despite the fact that recent paleogeographic reconstructions place the Iceland hotspot far from Baffin Island at the time of eruption (61 Ma). Our results also demonstrate that high-³He/â´He mantle reservoirs have ³He/²²Ne variability that either reflects ancient mantle heterogeneity or helium addition in the upper or lower mantle. © 2021 Elsevier B.V. Received 7 October 2020, Revised 11 December 2020, Accepted 11 January 2021, Available online 25 January 2021. The National Science Foundation (award #1911699) funded this research. The Woods Hole Oceanographic Institution (WHOI) Andrew W. Mellon Foundation Endowed Fund for Innovative Research and a National Geographic Society grant (#CP4-144R-18) supported fieldwork activities. The WHOI noble gas lab was supported by NSF OCE #1259218 and WHOI. We thank Maryse Mahy of the Parks Canada Nunavut Field Unit, the Qikiqtani Inuit Association, and the Nunavut Research Institute for their assistance and cooperation. Victoria Hooton provided invaluable help ... Article in Journal/Newspaper Baffin Island Baffin Iceland inuit Nunavut Caltech Authors (California Institute of Technology) Baffin Island Canada Nunavut Earth and Planetary Science Letters 558 116762 |
institution |
Open Polar |
collection |
Caltech Authors (California Institute of Technology) |
op_collection_id |
ftcaltechauth |
language |
unknown |
topic |
primordial mantle hotspot lavas neon isotopes noble gas geochemistry |
spellingShingle |
primordial mantle hotspot lavas neon isotopes noble gas geochemistry Horton, F. Curtice, J. Farley, K. A. Kurz, M. D. Asimow, P. D. Treffkorn, J. Boyes, X. M. Primordial neon in high-³He/â´He Baffin Island olivines |
topic_facet |
primordial mantle hotspot lavas neon isotopes noble gas geochemistry |
description |
Paleocene basaltic lavas exposed on Baffin Island have the highest ³He/â´He found in any terrestrial igneous rocks and potentially contain the most pristine primordial mantle material exposed on Earth's surface. By vacuum-crushing large (1–3 g) olivine mineral separates, we extracted enough magmatic gas to obtain the first coupled helium, neon, and argon isotopic compositions of Baffin Island lavas. The five Baffin Island olivine samples have ³He/â´He ranging from 36.2 ± 0.6 to 48.6 ± 1.3 (1σ) times the atmospheric ratio (Ra), overlapping with the highest known mantle values. Neon isotopic results fall on a mixing line between atmosphere and a high ²â°Ne/²²Ne mantle endmember (with a maximum ²â°Ne/²²Ne of 12.2). The slope of this mixing line is indistinguishable from that in subglacial Holocene glass from Iceland, but distinct from other hotspots and mid-ocean ridge basalt trends. This result supports the hypothesis that Baffin Island and Iceland lavas share a common high-³He/â´He mantle component, despite the fact that recent paleogeographic reconstructions place the Iceland hotspot far from Baffin Island at the time of eruption (61 Ma). Our results also demonstrate that high-³He/â´He mantle reservoirs have ³He/²²Ne variability that either reflects ancient mantle heterogeneity or helium addition in the upper or lower mantle. © 2021 Elsevier B.V. Received 7 October 2020, Revised 11 December 2020, Accepted 11 January 2021, Available online 25 January 2021. The National Science Foundation (award #1911699) funded this research. The Woods Hole Oceanographic Institution (WHOI) Andrew W. Mellon Foundation Endowed Fund for Innovative Research and a National Geographic Society grant (#CP4-144R-18) supported fieldwork activities. The WHOI noble gas lab was supported by NSF OCE #1259218 and WHOI. We thank Maryse Mahy of the Parks Canada Nunavut Field Unit, the Qikiqtani Inuit Association, and the Nunavut Research Institute for their assistance and cooperation. Victoria Hooton provided invaluable help ... |
format |
Article in Journal/Newspaper |
author |
Horton, F. Curtice, J. Farley, K. A. Kurz, M. D. Asimow, P. D. Treffkorn, J. Boyes, X. M. |
author_facet |
Horton, F. Curtice, J. Farley, K. A. Kurz, M. D. Asimow, P. D. Treffkorn, J. Boyes, X. M. |
author_sort |
Horton, F. |
title |
Primordial neon in high-³He/â´He Baffin Island olivines |
title_short |
Primordial neon in high-³He/â´He Baffin Island olivines |
title_full |
Primordial neon in high-³He/â´He Baffin Island olivines |
title_fullStr |
Primordial neon in high-³He/â´He Baffin Island olivines |
title_full_unstemmed |
Primordial neon in high-³He/â´He Baffin Island olivines |
title_sort |
primordial neon in high-â³he/â´he baffin island olivines |
publisher |
Elsevier |
publishDate |
2021 |
url |
https://doi.org/10.1016/j.epsl.2021.116762 |
geographic |
Baffin Island Canada Nunavut |
geographic_facet |
Baffin Island Canada Nunavut |
genre |
Baffin Island Baffin Iceland inuit Nunavut |
genre_facet |
Baffin Island Baffin Iceland inuit Nunavut |
op_source |
Earth and Planetary Science Letters, 558, Art. No. 116762, (2021-03-15) |
op_relation |
https://doi.org/10.1016/j.epsl.2021.116762 oai:authors.library.caltech.edu:bmk75-a5e89 eprintid:108479 resolverid:CaltechAUTHORS:20210318-103515860 |
op_rights |
info:eu-repo/semantics/closedAccess Other |
op_doi |
https://doi.org/10.1016/j.epsl.2021.116762 |
container_title |
Earth and Planetary Science Letters |
container_volume |
558 |
container_start_page |
116762 |
_version_ |
1802642595046752256 |