气候变化领域集成服务门户(CCPortal): Ancient Refertilization Process Preserved in the Plagioclase Peridotites: An Example From the Shuanggou Ophiolite, Southwest China

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DOI	10.1029/2019JB017552
	Ancient Refertilization Process Preserved in the Plagioclase Peridotites: An Example From the Shuanggou Ophiolite, Southwest China
	Hu W.-J.; Zhong H.; Chu Z.-Y.; Zhu W.-G.; Bai Z.-J.; Zhang C.
发表日期	2020
ISSN	21699313
卷号	125 期号:1
英文摘要	Petrology, geochemistry, platinum group elements (PGEs: Os, Ir, Ru, Rh, Pt, and Pd), and Re-Os isotope data of harzburgites and plagioclase lherzolites from the Shuanggou ophiolite (southwest China) are presented in this study, in order to determine whether ancient refertilization process can be preserved in ophiolitic plagioclase peridotites. The harzburgites in the Shuanggou ophiolite are divided into two groups: (1) the Group-1 harzburgites have 187Os/188Os ratios (0.12297–0.12727) and PGE abundances similar to those of oceanic peridotites, thereby representing the convecting upper mantle; (2) the Group-2 harzburgites have extremely low 187Os/188Os ratios (0.11307–0.11651) with considerable fractionation in iridium group PGEs (Os, Ir, and Ru), indicative of an ancient refractory mantle in the oceanic lithosphere. The plagioclase lherzolites were formed by melt impregnation of the Group-2 harzburgites, according to the PGE compositions and the petrographic features. However, the large Os isotope difference between the lherzolites (187Os/188Os: 0.12470–0.12666) and the Group-2 harzburgites indicates that the refertilization process took place much earlier than the exhumation of the mantle at 0.4 Ga. In addition, clinopyroxene composition suggests that the percolating melt is different from the Shuanggou diabases and typical mid-ocean ridge basalts. This study therefore demonstrates that some plagioclase lherzolites possibly were not related to mantle exhumation beneath the spreading center but formed by much older melt impregnation processes in the mantle instead. ©2019. American Geophysical Union. All Rights Reserved.
英文关键词	mantle refertilization; platinum group elements; Re-Os isotopes; Shuanggou ophiolite
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/188049
作者单位	State Key Laboratory of Ore Deposit Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, China; Department of Earth Sciences, University of Hong Kong, Hong Kong; College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing, China; State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, China
推荐引用方式 GB/T 7714	Hu W.-J.,Zhong H.,Chu Z.-Y.,et al. Ancient Refertilization Process Preserved in the Plagioclase Peridotites: An Example From the Shuanggou Ophiolite, Southwest China[J],2020,125(1).
APA	Hu W.-J.,Zhong H.,Chu Z.-Y.,Zhu W.-G.,Bai Z.-J.,&Zhang C..(2020).Ancient Refertilization Process Preserved in the Plagioclase Peridotites: An Example From the Shuanggou Ophiolite, Southwest China.Journal of Geophysical Research: Solid Earth,125(1).
MLA	Hu W.-J.,et al."Ancient Refertilization Process Preserved in the Plagioclase Peridotites: An Example From the Shuanggou Ophiolite, Southwest China".Journal of Geophysical Research: Solid Earth 125.1(2020).