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Discovery of natural MgSiO(3) tetragonal garnet in a shocked chondritic meteorite

MgSiO(3) tetragonal garnet, which is the last of the missing phases of experimentally predicted high-pressure polymorphs of pyroxene, has been discovered in a shocked meteorite. The garnet is formed from low-Ca pyroxene in the host rock through a solid-state transformation at 17 to 20 GPa and 1900°...

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Autores principales: Tomioka, Naotaka, Miyahara, Masaaki, Ito, Motoo
Formato: Online Artículo Texto
Lenguaje:English
Publicado: American Association for the Advancement of Science 2016
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4820389/
https://www.ncbi.nlm.nih.gov/pubmed/27051873
http://dx.doi.org/10.1126/sciadv.1501725
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author Tomioka, Naotaka
Miyahara, Masaaki
Ito, Motoo
author_facet Tomioka, Naotaka
Miyahara, Masaaki
Ito, Motoo
author_sort Tomioka, Naotaka
collection PubMed
description MgSiO(3) tetragonal garnet, which is the last of the missing phases of experimentally predicted high-pressure polymorphs of pyroxene, has been discovered in a shocked meteorite. The garnet is formed from low-Ca pyroxene in the host rock through a solid-state transformation at 17 to 20 GPa and 1900° to 2000°C. On the basis of the degree of cation ordering in its crystal structure, which can be deduced from electron diffraction intensities, the cooling rate of the shock-induced melt veins from ~2000°C was estimated to be higher than 10(3)°C/s. This cooling rate sets the upper bound for the shock-temperature increase in the bulk meteorite at ~900°C.
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spelling pubmed-48203892016-04-05 Discovery of natural MgSiO(3) tetragonal garnet in a shocked chondritic meteorite Tomioka, Naotaka Miyahara, Masaaki Ito, Motoo Sci Adv Research Articles MgSiO(3) tetragonal garnet, which is the last of the missing phases of experimentally predicted high-pressure polymorphs of pyroxene, has been discovered in a shocked meteorite. The garnet is formed from low-Ca pyroxene in the host rock through a solid-state transformation at 17 to 20 GPa and 1900° to 2000°C. On the basis of the degree of cation ordering in its crystal structure, which can be deduced from electron diffraction intensities, the cooling rate of the shock-induced melt veins from ~2000°C was estimated to be higher than 10(3)°C/s. This cooling rate sets the upper bound for the shock-temperature increase in the bulk meteorite at ~900°C. American Association for the Advancement of Science 2016-03-25 /pmc/articles/PMC4820389/ /pubmed/27051873 http://dx.doi.org/10.1126/sciadv.1501725 Text en Copyright © 2016, The Authors http://creativecommons.org/licenses/by-nc/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial license (http://creativecommons.org/licenses/by-nc/4.0/) , which permits use, distribution, and reproduction in any medium, so long as the resultant use is not for commercial advantage and provided the original work is properly cited.
spellingShingle Research Articles
Tomioka, Naotaka
Miyahara, Masaaki
Ito, Motoo
Discovery of natural MgSiO(3) tetragonal garnet in a shocked chondritic meteorite
title Discovery of natural MgSiO(3) tetragonal garnet in a shocked chondritic meteorite
title_full Discovery of natural MgSiO(3) tetragonal garnet in a shocked chondritic meteorite
title_fullStr Discovery of natural MgSiO(3) tetragonal garnet in a shocked chondritic meteorite
title_full_unstemmed Discovery of natural MgSiO(3) tetragonal garnet in a shocked chondritic meteorite
title_short Discovery of natural MgSiO(3) tetragonal garnet in a shocked chondritic meteorite
title_sort discovery of natural mgsio(3) tetragonal garnet in a shocked chondritic meteorite
topic Research Articles
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4820389/
https://www.ncbi.nlm.nih.gov/pubmed/27051873
http://dx.doi.org/10.1126/sciadv.1501725
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