Origin of magmatic harzburgite as a result of boninite magma evolution - An illustration using layered harzburgite-dunite cumulate from the Troodos ophiolite complex

doi:10.1016/j.lithos.2020.105764

CORC > 海洋研究所 > 中国科学院海洋研究所

	Origin of magmatic harzburgite as a result of boninite magma evolution - An illustration using layered harzburgite-dunite cumulate from the Troodos ophiolite complex
	Shen, Fangyu 2,3,4,5; Niu, Yaoling 1,2,3,4; Chen, Yanhong 1,3; Gao, Yajie 6; Wang, Xiaohong 2,4; Duan, Meng 2,4; Shan, Li 2,4,5
刊名	LITHOS
	2020-12-01
卷号	376 页码:16
关键词	Cumulate harzburgite Petrogenesis Boninite magma evolution Troodos ophiolite Fractional crystallization
ISSN号	0024-4937
DOI	10.1016/j.lithos.2020.105764
通讯作者	Shen, Fangyu(fangyushen@qdio.ac.cn) ; Niu, Yaoling(yaoling.niu@durham.ac.uk)
英文摘要	Olivine (Ol) and orthopyroxene (Opx) are the primary liquidus phases of boninite inmodern subduction settings and in many ophiolite complexes. It is thus straightforward to expect the formation of harzburgite cumulate resulting from boninite magma evolution. However, such magmatic harzburgite has been rarely studied. Here, we report the results of our study on such harzburgite from the Troodos ophiolite complex. The Troodos cumulate harzburgite (locally lherzolite) is characteristically interlayered with dunite, showing varying thickness onmillimeter to decimeter scales, as the result of volumetrically varyingmultiple pulses of melt injection into the evolvingmagma chamber. We illustrate the development of the interlayered cumulate by phase equilibrium analysis. The parental melt of each pulse begins to crystallize olivine to form a dunite layer before reaching the Ol-Opx cotectic, along which Ol and Opx coprecipitate to form a harzburgite layer. Periodical replenishment will result in dunite-harzburgite interlayered cumulate. In cases when replenishment may be delayed, the melt along the Ol-Opx cotectic can evolve to the Ol-Opx-clinopyroxene (Cpx) eutectic to form harzburgite with some Cpx or lherzolite. The calculated melts in equilibrium with spinels in the cumulate are characteristic of boninite in major element compositional spaces. The calculated melts in equilibrium with Cpx and Opx in the cumulate share the same as, or identical to, trace element patterns of the Troodos boninite (both glasses and bulk-rock compositions). Petrological modeling of the boninite magma evolution shows a crystallization order of Ol, Opx, Cpx, plagioclase. Our study also emphasizes the importance in considering dunite-harzburgite/lherzolite cumulatewhen interpreting seismic structure of the crust in subduction settings, especially in rock sequences associated with subduction initiation thought to be indicated by boninite magmatism. (C) 2020 Elsevier B.V. All rights reserved.
资助项目	National Natural Science Foundation of China[91958215] ; National Natural Science Foundation of China[41630968] ; NSFC-Shandong Joint Fund for Marine Science Research Centers[U1606401] ; Qingdao National Laboratory for Marine Science and Technology[2015ASKJ03] ; 111 Project[B18048]
WOS研究方向	Geochemistry & Geophysics ; Mineralogy
语种	英语
出版者	ELSEVIER
WOS记录号	WOS:000580897000029
内容类型	期刊论文
源URL	[http://ir.qdio.ac.cn/handle/337002/169150]
专题	中国科学院海洋研究所
通讯作者	Shen, Fangyu; Niu, Yaoling
作者单位	1.China Univ Geosci, Sch Earth Sci & Resources, Beijing 100083, Peoples R China 2.Chinese Acad Sci, Inst Oceanol, Qingdao 266071, Peoples R China 3.Univ Durham, Dept Earth Sci, Durham DH1 3LE, England 4.Qingdao Natl Lab Marine Sci & Technol, Lab Marine Geol, Qingdao 266061, Peoples R China 5.Univ Chinese Acad Sci, Beijing 100049, Peoples R China 6.Australian Natl Univ, Res Sch Earth Sci, Canberra, ACT 2601, Australia
推荐引用方式 GB/T 7714	Shen, Fangyu,Niu, Yaoling,Chen, Yanhong,et al. Origin of magmatic harzburgite as a result of boninite magma evolution - An illustration using layered harzburgite-dunite cumulate from the Troodos ophiolite complex[J]. LITHOS,2020,376:16.
APA	Shen, Fangyu.,Niu, Yaoling.,Chen, Yanhong.,Gao, Yajie.,Wang, Xiaohong.,...&Shan, Li.(2020).Origin of magmatic harzburgite as a result of boninite magma evolution - An illustration using layered harzburgite-dunite cumulate from the Troodos ophiolite complex.LITHOS,376,16.
MLA	Shen, Fangyu,et al."Origin of magmatic harzburgite as a result of boninite magma evolution - An illustration using layered harzburgite-dunite cumulate from the Troodos ophiolite complex".LITHOS 376(2020):16.