Iron isotope, major and trace element characterization of early Archean supracrustal rocks from SW Greenland: Protolith identification and metamorphic overprint
International audience The iron isotope, trace and major element compositions of Eoarchean supracrustal rocks from southern West Greenland (Isua Supracrustal Belt, the islands of Akilia and Innersuartuut) were analyzed in order to identify protoliths and characterize the imprints of metamorphism and...
Published in: | Geochimica et Cosmochimica Acta |
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ftinsu:oai:HAL:hal-00311041v1 2023-06-18T03:40:55+02:00 Iron isotope, major and trace element characterization of early Archean supracrustal rocks from SW Greenland: Protolith identification and metamorphic overprint Dauphas, Nicolas van Zuilen, Mark Busigny, Vincent Lepland, Aivo Wadhwa, Meenakshi E. Janney, Philip Institut de Physique du Globe de Paris (IPGP) Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS) Origins Laboratory Chicago Department of Geophysical Sciences Chicago University of Chicago-University of Chicago-Enrico Fermi Institute University of Chicago 2007 https://hal.science/hal-00311041 https://doi.org/10.1016/j.gca.2007.07.019 en eng HAL CCSD Elsevier info:eu-repo/semantics/altIdentifier/doi/10.1016/j.gca.2007.07.019 hal-00311041 https://hal.science/hal-00311041 doi:10.1016/j.gca.2007.07.019 ISSN: 0016-7037 EISSN: 0016-7037 Geochimica et Cosmochimica Acta https://hal.science/hal-00311041 Geochimica et Cosmochimica Acta, 2007, 71, pp.4745-4770. ⟨10.1016/j.gca.2007.07.019⟩ [SDU.STU.HY]Sciences of the Universe [physics]/Earth Sciences/Hydrology info:eu-repo/semantics/article Journal articles 2007 ftinsu https://doi.org/10.1016/j.gca.2007.07.019 2023-06-05T22:02:46Z International audience The iron isotope, trace and major element compositions of Eoarchean supracrustal rocks from southern West Greenland (Isua Supracrustal Belt, the islands of Akilia and Innersuartuut) were analyzed in order to identify protoliths and characterize the imprints of metamorphism and metasomatism. Banded iron formations (BIFs) from the Isua Supracrustal Belt (ISB) have trace element characteristics that are consistent with seawater derivation, including high Y/Ho ratios, positive Eu/Eu* anomalies, positive La/La* anomalies, and concave upward REE patterns. These rocks also have heavy Fe isotopic compositions relative to surrounding igneous rocks (not, vert, similar+0.4‰/amu). The most likely interpretation is that this signature was inherited from partial oxidation in a marine setting of Fe emanating from a source similar to modern mid-ocean ridge hydrothermal vents (not, vert, similar−0.15‰/amu). Banded quartz-rich rocks from the island of Akilia with high Fe/Ti ratios share many similarities with bona fide BIFs from Isua (heavy Fe isotopic compositions up to +0.4‰/amu, elevated Y/Ho ratios compared to igneous rocks, sometimes positive Eu/Eu* anomalies) suggesting a chemical sedimentary origin. Iron-poor metacarbonates from the southwestern part of the ISB have light Fe isotopic compositions (not, vert, similar−0.4‰/amu). This is consistent with derivation of these rocks by fluid flow through surrounding ultramafic rocks and deposition as metasomatic carbonates. Iron-rich metacarbonates from the northwest and northeast parts of the ISB have Fe isotopic compositions (from +0.1 to +0.4‰/amu) and trace element patterns (high Y/Ho ratios, positive Eu/Eu* and La/La* anomalies, and concave upward REE) similar to associated BIFs. The most likely interpretation is that these iron-rich metacarbonates were derived from mobilization of Fe in BIFs by metasomatic fluids. Article in Journal/Newspaper Greenland Institut national des sciences de l'Univers: HAL-INSU Greenland Geochimica et Cosmochimica Acta 71 19 4745 4770 |
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Open Polar |
collection |
Institut national des sciences de l'Univers: HAL-INSU |
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ftinsu |
language |
English |
topic |
[SDU.STU.HY]Sciences of the Universe [physics]/Earth Sciences/Hydrology |
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[SDU.STU.HY]Sciences of the Universe [physics]/Earth Sciences/Hydrology Dauphas, Nicolas van Zuilen, Mark Busigny, Vincent Lepland, Aivo Wadhwa, Meenakshi E. Janney, Philip Iron isotope, major and trace element characterization of early Archean supracrustal rocks from SW Greenland: Protolith identification and metamorphic overprint |
topic_facet |
[SDU.STU.HY]Sciences of the Universe [physics]/Earth Sciences/Hydrology |
description |
International audience The iron isotope, trace and major element compositions of Eoarchean supracrustal rocks from southern West Greenland (Isua Supracrustal Belt, the islands of Akilia and Innersuartuut) were analyzed in order to identify protoliths and characterize the imprints of metamorphism and metasomatism. Banded iron formations (BIFs) from the Isua Supracrustal Belt (ISB) have trace element characteristics that are consistent with seawater derivation, including high Y/Ho ratios, positive Eu/Eu* anomalies, positive La/La* anomalies, and concave upward REE patterns. These rocks also have heavy Fe isotopic compositions relative to surrounding igneous rocks (not, vert, similar+0.4‰/amu). The most likely interpretation is that this signature was inherited from partial oxidation in a marine setting of Fe emanating from a source similar to modern mid-ocean ridge hydrothermal vents (not, vert, similar−0.15‰/amu). Banded quartz-rich rocks from the island of Akilia with high Fe/Ti ratios share many similarities with bona fide BIFs from Isua (heavy Fe isotopic compositions up to +0.4‰/amu, elevated Y/Ho ratios compared to igneous rocks, sometimes positive Eu/Eu* anomalies) suggesting a chemical sedimentary origin. Iron-poor metacarbonates from the southwestern part of the ISB have light Fe isotopic compositions (not, vert, similar−0.4‰/amu). This is consistent with derivation of these rocks by fluid flow through surrounding ultramafic rocks and deposition as metasomatic carbonates. Iron-rich metacarbonates from the northwest and northeast parts of the ISB have Fe isotopic compositions (from +0.1 to +0.4‰/amu) and trace element patterns (high Y/Ho ratios, positive Eu/Eu* and La/La* anomalies, and concave upward REE) similar to associated BIFs. The most likely interpretation is that these iron-rich metacarbonates were derived from mobilization of Fe in BIFs by metasomatic fluids. |
author2 |
Institut de Physique du Globe de Paris (IPGP) Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS) Origins Laboratory Chicago Department of Geophysical Sciences Chicago University of Chicago-University of Chicago-Enrico Fermi Institute University of Chicago |
format |
Article in Journal/Newspaper |
author |
Dauphas, Nicolas van Zuilen, Mark Busigny, Vincent Lepland, Aivo Wadhwa, Meenakshi E. Janney, Philip |
author_facet |
Dauphas, Nicolas van Zuilen, Mark Busigny, Vincent Lepland, Aivo Wadhwa, Meenakshi E. Janney, Philip |
author_sort |
Dauphas, Nicolas |
title |
Iron isotope, major and trace element characterization of early Archean supracrustal rocks from SW Greenland: Protolith identification and metamorphic overprint |
title_short |
Iron isotope, major and trace element characterization of early Archean supracrustal rocks from SW Greenland: Protolith identification and metamorphic overprint |
title_full |
Iron isotope, major and trace element characterization of early Archean supracrustal rocks from SW Greenland: Protolith identification and metamorphic overprint |
title_fullStr |
Iron isotope, major and trace element characterization of early Archean supracrustal rocks from SW Greenland: Protolith identification and metamorphic overprint |
title_full_unstemmed |
Iron isotope, major and trace element characterization of early Archean supracrustal rocks from SW Greenland: Protolith identification and metamorphic overprint |
title_sort |
iron isotope, major and trace element characterization of early archean supracrustal rocks from sw greenland: protolith identification and metamorphic overprint |
publisher |
HAL CCSD |
publishDate |
2007 |
url |
https://hal.science/hal-00311041 https://doi.org/10.1016/j.gca.2007.07.019 |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland |
genre_facet |
Greenland |
op_source |
ISSN: 0016-7037 EISSN: 0016-7037 Geochimica et Cosmochimica Acta https://hal.science/hal-00311041 Geochimica et Cosmochimica Acta, 2007, 71, pp.4745-4770. ⟨10.1016/j.gca.2007.07.019⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1016/j.gca.2007.07.019 hal-00311041 https://hal.science/hal-00311041 doi:10.1016/j.gca.2007.07.019 |
op_doi |
https://doi.org/10.1016/j.gca.2007.07.019 |
container_title |
Geochimica et Cosmochimica Acta |
container_volume |
71 |
container_issue |
19 |
container_start_page |
4745 |
op_container_end_page |
4770 |
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1769006271490424832 |