Partial melting of a C-rich asteroid: Lithophile trace elements in ureilites
International audience Ureilites are among the most common achondrites and are widely believed to sample the mantle of a single, now-disrupted, C-rich body. We analyzed 17 ureilite samples, mostly Antarctic finds, and determined their incompatible trace element abundances. In order to remove or redu...
Published in: | Geochimica et Cosmochimica Acta |
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Online Access: | https://hal.sorbonne-universite.fr/hal-01365231 https://hal.sorbonne-universite.fr/hal-01365231/document https://hal.sorbonne-universite.fr/hal-01365231/file/GCA_UPB_litho_elem_16.pdf https://doi.org/10.1016/j.gca.2016.08.042 |
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ftsorbonneuniv:oai:HAL:hal-01365231v1 2024-09-15T17:46:18+00:00 Partial melting of a C-rich asteroid: Lithophile trace elements in ureilites Barrat, Jean-Alix, J-A Jambon, Albert Yamaguchi, Akira Bischoff, Addi Rouget, Marie-Laure Liorzou, Céline, C. Domaines Océaniques (LDO) Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Observatoire des Sciences de l'Univers-Institut d'écologie et environnement-Centre National de la Recherche Scientifique (CNRS) Institut des Sciences de la Terre de Paris (iSTeP) Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS) National Institute of Polar Research Tokyo (NiPR) Graduate University for Advanced Sciences Westfälische Wilhelms-Universität Münster = University of Münster (WWU) Université de Brest (UBO) 2016-09 https://hal.sorbonne-universite.fr/hal-01365231 https://hal.sorbonne-universite.fr/hal-01365231/document https://hal.sorbonne-universite.fr/hal-01365231/file/GCA_UPB_litho_elem_16.pdf https://doi.org/10.1016/j.gca.2016.08.042 en eng HAL CCSD Elsevier info:eu-repo/semantics/altIdentifier/doi/10.1016/j.gca.2016.08.042 hal-01365231 https://hal.sorbonne-universite.fr/hal-01365231 https://hal.sorbonne-universite.fr/hal-01365231/document https://hal.sorbonne-universite.fr/hal-01365231/file/GCA_UPB_litho_elem_16.pdf doi:10.1016/j.gca.2016.08.042 info:eu-repo/semantics/OpenAccess ISSN: 0016-7037 EISSN: 0016-7037 Geochimica et Cosmochimica Acta https://hal.sorbonne-universite.fr/hal-01365231 Geochimica et Cosmochimica Acta, 2016, 194, pp.163-178. ⟨10.1016/j.gca.2016.08.042⟩ partial melting 21 achondrite ureilite trace elements [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry info:eu-repo/semantics/article Journal articles 2016 ftsorbonneuniv https://doi.org/10.1016/j.gca.2016.08.042 2024-07-11T23:34:40Z International audience Ureilites are among the most common achondrites and are widely believed to sample the mantle of a single, now-disrupted, C-rich body. We analyzed 17 ureilite samples, mostly Antarctic finds, and determined their incompatible trace element abundances. In order to remove or reduce the terrestrial contamination, which is marked among Antarctic ureilites by light-REE enrichment, we leached the powdered samples with nitric acid. The residues display consistent abundances, which strongly resemble those of the pristine rocks. All the analyzed samples display light-REE depletions, negative Eu anomalies, low (Sr/Eu∗)n, and (Zr/Eu∗)n ratios which are correlated. Two groups of ureilites (groups A and B) are defined. Compared to group A, group B ureilites, which are the less numerous, tend to be richer in heavy REEs, more light-REE depleted, and display among the deepest Eu anomalies. In addition, olivine cores in group B ureilites tend to be more forsteritic (Mg# = 81.9-95.2) than in group A ureilites (Mg# = 74.7-86.1). Incompatible trace element systematics supports the view that ureilites are mantle restites. REE modelling suggests that their precursors were rather REE-rich (ca. 1.8-2 x CI) and contained a phosphate phase, possibly merrillite. The REE abundances in ureilites can be explained if at least two distinct types of magmas were removed successively from their precursors: aluminous and alkali-rich melts as exemplified by the Almahata Sitta trachyandesite (ALM-A), and Al and alkali-poor melts produced after the exhaustion of plagioclase from the source. Partial melting was near fractional (group B ureilites, which are probably among the least residual samples) to dynamic with melt porosities that did not exceed a couple of percent (group A ureilites). The ureilite parent body (UPB) was almost certainly covered by a crust formed chiefly from the extrusion products of the aluminous and alkali-rich magmas. It is currently uncertain whether the Al and alkali-poor melts produced during the ... Article in Journal/Newspaper Antarc* Antarctic HAL Sorbonne Université Geochimica et Cosmochimica Acta 194 163 178 |
institution |
Open Polar |
collection |
HAL Sorbonne Université |
op_collection_id |
ftsorbonneuniv |
language |
English |
topic |
partial melting 21 achondrite ureilite trace elements [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry |
spellingShingle |
partial melting 21 achondrite ureilite trace elements [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry Barrat, Jean-Alix, J-A Jambon, Albert Yamaguchi, Akira Bischoff, Addi Rouget, Marie-Laure Liorzou, Céline, C. Partial melting of a C-rich asteroid: Lithophile trace elements in ureilites |
topic_facet |
partial melting 21 achondrite ureilite trace elements [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry |
description |
International audience Ureilites are among the most common achondrites and are widely believed to sample the mantle of a single, now-disrupted, C-rich body. We analyzed 17 ureilite samples, mostly Antarctic finds, and determined their incompatible trace element abundances. In order to remove or reduce the terrestrial contamination, which is marked among Antarctic ureilites by light-REE enrichment, we leached the powdered samples with nitric acid. The residues display consistent abundances, which strongly resemble those of the pristine rocks. All the analyzed samples display light-REE depletions, negative Eu anomalies, low (Sr/Eu∗)n, and (Zr/Eu∗)n ratios which are correlated. Two groups of ureilites (groups A and B) are defined. Compared to group A, group B ureilites, which are the less numerous, tend to be richer in heavy REEs, more light-REE depleted, and display among the deepest Eu anomalies. In addition, olivine cores in group B ureilites tend to be more forsteritic (Mg# = 81.9-95.2) than in group A ureilites (Mg# = 74.7-86.1). Incompatible trace element systematics supports the view that ureilites are mantle restites. REE modelling suggests that their precursors were rather REE-rich (ca. 1.8-2 x CI) and contained a phosphate phase, possibly merrillite. The REE abundances in ureilites can be explained if at least two distinct types of magmas were removed successively from their precursors: aluminous and alkali-rich melts as exemplified by the Almahata Sitta trachyandesite (ALM-A), and Al and alkali-poor melts produced after the exhaustion of plagioclase from the source. Partial melting was near fractional (group B ureilites, which are probably among the least residual samples) to dynamic with melt porosities that did not exceed a couple of percent (group A ureilites). The ureilite parent body (UPB) was almost certainly covered by a crust formed chiefly from the extrusion products of the aluminous and alkali-rich magmas. It is currently uncertain whether the Al and alkali-poor melts produced during the ... |
author2 |
Domaines Océaniques (LDO) Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Observatoire des Sciences de l'Univers-Institut d'écologie et environnement-Centre National de la Recherche Scientifique (CNRS) Institut des Sciences de la Terre de Paris (iSTeP) Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS) National Institute of Polar Research Tokyo (NiPR) Graduate University for Advanced Sciences Westfälische Wilhelms-Universität Münster = University of Münster (WWU) Université de Brest (UBO) |
format |
Article in Journal/Newspaper |
author |
Barrat, Jean-Alix, J-A Jambon, Albert Yamaguchi, Akira Bischoff, Addi Rouget, Marie-Laure Liorzou, Céline, C. |
author_facet |
Barrat, Jean-Alix, J-A Jambon, Albert Yamaguchi, Akira Bischoff, Addi Rouget, Marie-Laure Liorzou, Céline, C. |
author_sort |
Barrat, Jean-Alix, J-A |
title |
Partial melting of a C-rich asteroid: Lithophile trace elements in ureilites |
title_short |
Partial melting of a C-rich asteroid: Lithophile trace elements in ureilites |
title_full |
Partial melting of a C-rich asteroid: Lithophile trace elements in ureilites |
title_fullStr |
Partial melting of a C-rich asteroid: Lithophile trace elements in ureilites |
title_full_unstemmed |
Partial melting of a C-rich asteroid: Lithophile trace elements in ureilites |
title_sort |
partial melting of a c-rich asteroid: lithophile trace elements in ureilites |
publisher |
HAL CCSD |
publishDate |
2016 |
url |
https://hal.sorbonne-universite.fr/hal-01365231 https://hal.sorbonne-universite.fr/hal-01365231/document https://hal.sorbonne-universite.fr/hal-01365231/file/GCA_UPB_litho_elem_16.pdf https://doi.org/10.1016/j.gca.2016.08.042 |
genre |
Antarc* Antarctic |
genre_facet |
Antarc* Antarctic |
op_source |
ISSN: 0016-7037 EISSN: 0016-7037 Geochimica et Cosmochimica Acta https://hal.sorbonne-universite.fr/hal-01365231 Geochimica et Cosmochimica Acta, 2016, 194, pp.163-178. ⟨10.1016/j.gca.2016.08.042⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1016/j.gca.2016.08.042 hal-01365231 https://hal.sorbonne-universite.fr/hal-01365231 https://hal.sorbonne-universite.fr/hal-01365231/document https://hal.sorbonne-universite.fr/hal-01365231/file/GCA_UPB_litho_elem_16.pdf doi:10.1016/j.gca.2016.08.042 |
op_rights |
info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.1016/j.gca.2016.08.042 |
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Geochimica et Cosmochimica Acta |
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