气候变化领域集成服务门户(CCPortal): Feedback of Slab Distortion on Volcanic Arc Evolution: Geochemical Perspective From Late Cenozoic Volcanism in SW Japan

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DOI	10.1029/2019JB019143
	Feedback of Slab Distortion on Volcanic Arc Evolution: Geochemical Perspective From Late Cenozoic Volcanism in SW Japan
	Nguyen T.T.; Kitagawa H.; Pineda-Velasco I.; Nakamura E.
发表日期	2020
ISSN	21699313
卷号	125 期号:10
英文摘要	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. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	basalt; mantle; slab; subduction zone; volcanism
语种	英语
来源期刊	Journal of Geophysical Research: Solid Earth
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/187579
作者单位	Pheasant Memorial Laboratory, Institute for Planetary Materials, Okayama University, Misasa, Tottori, Japan; Now at Institute of Earth Sciences, Academia Sinica, Taipei, Taiwan; Now at Department of Geology, Hanoi University of Mining and Geology, Hanoi, Viet Nam
推荐引用方式 GB/T 7714	Nguyen T.T.,Kitagawa H.,Pineda-Velasco I.,et al. Feedback of Slab Distortion on Volcanic Arc Evolution: Geochemical Perspective From Late Cenozoic Volcanism in SW Japan[J],2020,125(10).
APA	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(10).
MLA	Nguyen T.T.,et al."Feedback of Slab Distortion on Volcanic Arc Evolution: Geochemical Perspective From Late Cenozoic Volcanism in SW Japan".Journal of Geophysical Research: Solid Earth 125.10(2020).