ID | 63509 |
フルテキストURL | |
著者 |
Nguyen, Tai Truong
Pheasant Memorial Laboratory, Institute for Planetary Materials, Okayama University
Kitagawa, Hiroshi
Pheasant Memorial Laboratory, Institute for Planetary Materials, Okayama University
ORCID
publons
researchmap
Pineda‐Velasco, Ivan
Pheasant Memorial Laboratory, Institute for Planetary Materials, Okayama University
Nakamura, Eizo
Pheasant Memorial Laboratory, Institute for Planetary Materials, Okayama University
Kaken ID
publons
researchmap
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抄録 | Southwest Japan is an island arc formed by subduction of the Philippine Sea (PHS) plate. The Quaternary magmatism in this region is characterized by eruptions of high-Sr andesites and dacites, considered to have been derived by melting of the PHS plate. The loci of these volcanoes spatially coincide with seismic discontinuities of the subducted PHS plate. Thus, the magmatism is interpreted as the result of slab melting at the plate tears. However, the processes that promote slab tearing remain unclear. In this study, we applied geochronological and geochemical analyses to late Cenozoic volcanic rocks in southwest Japan as tracers of slab morphology. Two different magma types, ocean-island basalt (OIB) and island-arc basalt (IAB), have occurred over 12 million years (Myr). These two magmas are attributed to different integrations of melts extracted from an originally fertile mantle; the OIBs from high temperature melt (1,300–1,400°C) were extracted at a depth of 40–80 km, whereas the IABs were extracted from a shallower, lower temperature region (30–60 km, 1,200–1,350°C). Secular change in Sr enrichment of IAB likely arose due to a transition of slab-derived fluids, incorporated into magmas as they formed, from water- to melt-dominant one. Progressive shallowing of the subducted PHS plate is responsible for secular change in the properties of slab-derived fluids as well as rollback of OIB volcanoes. Production of chemically variable magmas in the Chugoku district is the surface expression of distorting slab morphology by interaction between mantle and the subducting plate.
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キーワード | subduction zone
volcanism
mantle
basalt
slab
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備考 | Nguyen, T. T., Kitagawa, H., Pineda-Velasco, I., & Nakamura, E. (2020). Feedback of slab distortion on volcanic arc evolution: Geochemical perspective from late Cenozoic volcanism in SW Japan. Journal of Geophysical Research: Solid Earth, 125, e2019JB019143. https://doi.org/10.1029/2019JB019143. To view the published open abstract, go to https://doi.org/10.1029/2019jb019143
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発行日 | 2020-10
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出版物タイトル |
Journal of Geophysical Research: Solid Earth
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巻 | 125巻
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号 | 10号
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出版者 | American Geophysical Union (AGU)
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開始ページ | e2019JB019143
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ISSN | 2169-9313
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資料タイプ |
学術雑誌論文
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言語 |
英語
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OAI-PMH Set |
岡山大学
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著作権者 | ©2020. American Geophysical Union. All Rights Reserved.
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論文のバージョン | publisher
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DOI | |
Web of Science KeyUT | |
関連URL | isVersionOf https://doi.org/10.1029/2019jb019143
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Citation | Nguyen, T. T., Kitagawa, H., Pineda-Velasco, I., & Nakamura, E. (2020). Feedback of slab distortion on volcanic arc evolution: Geochemical perspective from late Cenozoic volcanism in SW Japan. Journal of Geophysical Research: Solid Earth, 125, e2019JB019143. https://doi.org/10.1029/2019JB019143
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助成機関名 |
Ministry of Education, Culture, Sports, Science and Technology
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