Titanian Clinohumite-Bearing Peridotite from the Ulamertoq Ultramafic Body in the 3.0 Ga Akia Terrane of Southern West Greenland
A titanian clinohumite-bearing dunite was recently found in the Ulamertoq ultramafic body within the 3.0 Ga Akia Terrane of southern West Greenland. Titanian clinohumite occurs as disseminated and discrete grains. Titanian clinohumite contains relatively high amounts of fluorine, reaching up to 2.4...
Published in: | Geosciences |
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2019
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Online Access: | https://curis.ku.dk/portal/da/publications/titanian-clinohumitebearing-peridotite-from-the-ulamertoq-ultramafic-body-in-the-30-ga-akia-terrane-of-southern-west-greenland(e38b6667-aa26-4e1e-b54b-d16c3367870a).html https://doi.org/10.3390/geosciences9040153 https://curis.ku.dk/ws/files/215788641/2019_Nishio_et_al._Geosciences_Ulamertoq_clinohumite.pdf |
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ftcopenhagenunip:oai:pure.atira.dk:publications/e38b6667-aa26-4e1e-b54b-d16c3367870a 2024-05-19T07:41:15+00:00 Titanian Clinohumite-Bearing Peridotite from the Ulamertoq Ultramafic Body in the 3.0 Ga Akia Terrane of Southern West Greenland Nishio, Ikuya Morishita, Tomoaki Szilas, Kristoffer Pearson, Graham Tani, Ken-Ichiro Tamura, Akihiro Harigane, Yumiko Guotana, Juan Miguel 2019 application/pdf https://curis.ku.dk/portal/da/publications/titanian-clinohumitebearing-peridotite-from-the-ulamertoq-ultramafic-body-in-the-30-ga-akia-terrane-of-southern-west-greenland(e38b6667-aa26-4e1e-b54b-d16c3367870a).html https://doi.org/10.3390/geosciences9040153 https://curis.ku.dk/ws/files/215788641/2019_Nishio_et_al._Geosciences_Ulamertoq_clinohumite.pdf eng eng info:eu-repo/semantics/openAccess Nishio , I , Morishita , T , Szilas , K , Pearson , G , Tani , K-I , Tamura , A , Harigane , Y & Guotana , J M 2019 , ' Titanian Clinohumite-Bearing Peridotite from the Ulamertoq Ultramafic Body in the 3.0 Ga Akia Terrane of Southern West Greenland ' , Geosciences (Switzerland) , vol. 9 , no. 4 , 153 . https://doi.org/10.3390/geosciences9040153 article 2019 ftcopenhagenunip https://doi.org/10.3390/geosciences9040153 2024-05-02T00:33:09Z A titanian clinohumite-bearing dunite was recently found in the Ulamertoq ultramafic body within the 3.0 Ga Akia Terrane of southern West Greenland. Titanian clinohumite occurs as disseminated and discrete grains. Titanian clinohumite contains relatively high amounts of fluorine, reaching up to 2.4 wt.%. The high-Fo content of olivine (Fo93) coupled with low Cr/(Cr + Al) ratio of orthopyroxene implies that the dunite host is not of residual origin after melt extraction by partial melting of the primitive mantle. Olivine grains are classified into two types based on abundances of opaque mineral inclusions: (1) dusty inclusion-rich and (2) clear inclusion-free olivines. Opaque inclusions in coarse-grained olivines are mainly magnetite. Small amounts of ilmenite are also present around titanian clinohumite grains. The observed mineral association indicates partial replacement of titanian clinohumite to ilmenite (+magnetite) and olivine following the reaction: titanian clinohumite = ilmenite + olivine + hydrous fluid. The coexistence of F-bearing titanian clinohumite, olivine, and chromian chlorite indicates equilibration at around 800–900 °C under garnet-free conditions (<2 GPa). Petrological and mineralogical characteristics of the studied titanian clinohumite-bearing dunite are comparable to deserpentinized peridotites derived from former serpentinites. This study demonstrates the importance of considering the effects of hydration/dehydration processes for the origin of ultramafic bodies found in polymetamorphic Archaean terranes. Article in Journal/Newspaper Greenland University of Copenhagen: Research Geosciences 9 4 153 |
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Open Polar |
collection |
University of Copenhagen: Research |
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ftcopenhagenunip |
language |
English |
description |
A titanian clinohumite-bearing dunite was recently found in the Ulamertoq ultramafic body within the 3.0 Ga Akia Terrane of southern West Greenland. Titanian clinohumite occurs as disseminated and discrete grains. Titanian clinohumite contains relatively high amounts of fluorine, reaching up to 2.4 wt.%. The high-Fo content of olivine (Fo93) coupled with low Cr/(Cr + Al) ratio of orthopyroxene implies that the dunite host is not of residual origin after melt extraction by partial melting of the primitive mantle. Olivine grains are classified into two types based on abundances of opaque mineral inclusions: (1) dusty inclusion-rich and (2) clear inclusion-free olivines. Opaque inclusions in coarse-grained olivines are mainly magnetite. Small amounts of ilmenite are also present around titanian clinohumite grains. The observed mineral association indicates partial replacement of titanian clinohumite to ilmenite (+magnetite) and olivine following the reaction: titanian clinohumite = ilmenite + olivine + hydrous fluid. The coexistence of F-bearing titanian clinohumite, olivine, and chromian chlorite indicates equilibration at around 800–900 °C under garnet-free conditions (<2 GPa). Petrological and mineralogical characteristics of the studied titanian clinohumite-bearing dunite are comparable to deserpentinized peridotites derived from former serpentinites. This study demonstrates the importance of considering the effects of hydration/dehydration processes for the origin of ultramafic bodies found in polymetamorphic Archaean terranes. |
format |
Article in Journal/Newspaper |
author |
Nishio, Ikuya Morishita, Tomoaki Szilas, Kristoffer Pearson, Graham Tani, Ken-Ichiro Tamura, Akihiro Harigane, Yumiko Guotana, Juan Miguel |
spellingShingle |
Nishio, Ikuya Morishita, Tomoaki Szilas, Kristoffer Pearson, Graham Tani, Ken-Ichiro Tamura, Akihiro Harigane, Yumiko Guotana, Juan Miguel Titanian Clinohumite-Bearing Peridotite from the Ulamertoq Ultramafic Body in the 3.0 Ga Akia Terrane of Southern West Greenland |
author_facet |
Nishio, Ikuya Morishita, Tomoaki Szilas, Kristoffer Pearson, Graham Tani, Ken-Ichiro Tamura, Akihiro Harigane, Yumiko Guotana, Juan Miguel |
author_sort |
Nishio, Ikuya |
title |
Titanian Clinohumite-Bearing Peridotite from the Ulamertoq Ultramafic Body in the 3.0 Ga Akia Terrane of Southern West Greenland |
title_short |
Titanian Clinohumite-Bearing Peridotite from the Ulamertoq Ultramafic Body in the 3.0 Ga Akia Terrane of Southern West Greenland |
title_full |
Titanian Clinohumite-Bearing Peridotite from the Ulamertoq Ultramafic Body in the 3.0 Ga Akia Terrane of Southern West Greenland |
title_fullStr |
Titanian Clinohumite-Bearing Peridotite from the Ulamertoq Ultramafic Body in the 3.0 Ga Akia Terrane of Southern West Greenland |
title_full_unstemmed |
Titanian Clinohumite-Bearing Peridotite from the Ulamertoq Ultramafic Body in the 3.0 Ga Akia Terrane of Southern West Greenland |
title_sort |
titanian clinohumite-bearing peridotite from the ulamertoq ultramafic body in the 3.0 ga akia terrane of southern west greenland |
publishDate |
2019 |
url |
https://curis.ku.dk/portal/da/publications/titanian-clinohumitebearing-peridotite-from-the-ulamertoq-ultramafic-body-in-the-30-ga-akia-terrane-of-southern-west-greenland(e38b6667-aa26-4e1e-b54b-d16c3367870a).html https://doi.org/10.3390/geosciences9040153 https://curis.ku.dk/ws/files/215788641/2019_Nishio_et_al._Geosciences_Ulamertoq_clinohumite.pdf |
genre |
Greenland |
genre_facet |
Greenland |
op_source |
Nishio , I , Morishita , T , Szilas , K , Pearson , G , Tani , K-I , Tamura , A , Harigane , Y & Guotana , J M 2019 , ' Titanian Clinohumite-Bearing Peridotite from the Ulamertoq Ultramafic Body in the 3.0 Ga Akia Terrane of Southern West Greenland ' , Geosciences (Switzerland) , vol. 9 , no. 4 , 153 . https://doi.org/10.3390/geosciences9040153 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.3390/geosciences9040153 |
container_title |
Geosciences |
container_volume |
9 |
container_issue |
4 |
container_start_page |
153 |
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1799480855032233984 |