气候变化领域集成服务门户(CCPortal): Derivation of Jurassic HIMU-like intraplate basalts from mantle transition zone in South China: New geochemical constraints from olivine-hosted melt inclusion

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DOI	10.1016/j.lithos.2019.105337
	Derivation of Jurassic HIMU-like intraplate basalts from mantle transition zone in South China: New geochemical constraints from olivine-hosted melt inclusion
	Wu, Yangming; Guo, Feng; Wang, Xuan-Ce; Wilde, Simon A.; Fan, Weiming
通讯作者	Guo, F (通讯作者)
发表日期	2020
ISSN	0024-4937
EISSN	1872-6143
卷号	354
英文摘要	The petrogenesis of high-mu (HIMU, mu = U-238/Pb-204) basalt in a continental setting remains highly controversial. Here we present a comprehensive geochemical (including major and trace element and isotopic compositions of whole-rock, olivine and melt inclusion) data on Jurassic HIMU-like basalts from the interior (Antang) of South China. This study identified high-H2O (up to 5.0 wt%) olivine-hosted melt inclusions in these basalts. After stripping off the effects of degassing, post-entrapment crystallization and kinetic diffusion, the primary magma of the Antang basalts was estimated to contain >= 2.65 wt% H2O and the corresponding mantle source contains >1000 ppm H2O, which is much higher than the water content of convecting asthenosphere and lower mantle. In addition, the relative depletion of fluid-mobile elements and positive Nb-Ta anomalies in bulk rocks and melt inclusions, and the distance far away from the contemporaneous paleo-Pacific subduction zone, preclude an origin from a slab fluid-metasomatized mantle. The strong depletion of CaO in both olivine phenocrysts and whole-rock compositions further indicates that the basaltic magmas originated from an eclogitic or pyroxenitic mantle source. The combined geochemical data suggest that the Antang basalts were most likely derived from a hydrous source, which was composed mainly of ancient recycled oceanic crust that had stagnated in the mantle transition zone (MTZ) for more than one billion years. Our results therefore provide a new perspective on the MTZ origin of intracontinental basalts and imply that the hydrous MTZ can preserve recycled crustal components for long periods of time and form distinct mantle reservoirs for intraplate basalts. (C) 2019 Elsevier B.V. All rights reserved.
关键词	SUBDUCTED OCEANIC-CRUST OS ISOTOPIC EVIDENCE TRACE-ELEMENT WATER-CONTENT ISLAND BASALTS BENEATH ORIGIN LITHOSPHERE PHENOCRYSTS HAWAIIAN
英文关键词	Mantle transition zone; Hydrous; Melt inclusion; HIMU basalts; South China
语种	英语
WOS研究方向	Geochemistry & Geophysics ; Mineralogy
WOS类目	Geochemistry & Geophysics ; Mineralogy
WOS记录号	WOS:000514217200005
来源期刊	LITHOS
来源机构	中国科学院青藏高原研究所
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/259933
推荐引用方式 GB/T 7714	Wu, Yangming,Guo, Feng,Wang, Xuan-Ce,et al. Derivation of Jurassic HIMU-like intraplate basalts from mantle transition zone in South China: New geochemical constraints from olivine-hosted melt inclusion[J]. 中国科学院青藏高原研究所,2020,354.
APA	Wu, Yangming,Guo, Feng,Wang, Xuan-Ce,Wilde, Simon A.,&Fan, Weiming.(2020).Derivation of Jurassic HIMU-like intraplate basalts from mantle transition zone in South China: New geochemical constraints from olivine-hosted melt inclusion.LITHOS,354.
MLA	Wu, Yangming,et al."Derivation of Jurassic HIMU-like intraplate basalts from mantle transition zone in South China: New geochemical constraints from olivine-hosted melt inclusion".LITHOS 354(2020).