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DOI	10.1016/j.lithos.2015.02.023
	Re-Os isotopic constraints on the evolution of the Bangong-Nujiang Tethyan oceanic mantle, Central Tibet
	Huang, Qi-Shuai; Shi, Ren-Deng; O'Reilly, Suzanne Y.; Griffin, William L.; Zhang, Ming; Liu, De-Liang; Zhang, Xiao-Ran
通讯作者	Huang, QS (通讯作者)
发表日期	2015
ISSN	0024-4937
EISSN	1872-6143
起始页码	32
结束页码	45
卷号	224
英文摘要	Geochemical (including Re-Os isotopic) studies of the mantle rocks of ophiolites in the Bangong-Nujiang suture zone in central Tibet have provided a coherent picture of the evolution of the Bangong-Nujiang Tethyan oceanic mantle from mid-ocean ridge (MOR) to subduction-zone (SSZ) settings. Clinopyroxene (cpx)-harzburgites and lherzolites in the Bangong Lake ophiolite were formed in a MOR setting, as demonstrated by the Cr# of spinels (<0.60) and whole-rock LREE-depleted patterns. Suprachondritic Re-187/Os-188 ratios (up to 1.833) of cpx-harzburgites and their spinels can be explained by interaction with melts derived from high Re/Os sources. Re-depletion (T-RD) model ages (0.48-0.55 Ga) suggest these rocks may represent a Pan-African domain beneath the Gondwana continent. High TiO2 contents of spinels and whole-rock samples imply that the lherzolites were formed through a refertilization process. Similarly, Re-Os isotopic systematics of sulfides in the lherzolites (Re-187/Os-188: 0.173-1.717, Os-187/Os-188: 0.12646-0.17340) demonstrate that they are mixtures of primary and secondary sulfides. Os-187/Os-188 ratios (0.1211-0.1226) of whole-rock lherzolites give Ten ages of 0.73-0.97 Ga, indicating the presence of Neoproterozoic lithospheric mantle under the spreading ridges. Mantle rocks in the SSZ-type ophiolites from Bangong Lake, Dongqiao and Nagqu reflect the complex evolution of the Bangong-Nujiang oceanic mantle during the SSZ stage. Most harzburgites from the Bangong Lake ophiolite give Ten ages of 1.0-1.5 Ga, possibly representing relics of a Mesoproterozoic lithospheric mantle. However, three samples have both high Os contents (1.32-4.45 ppb) and near-chondritic Os-187/Os-188 (0.1260-0.1297), and may represent Mesozoic oceanic lithospheric mantle. Os-187/Os-188 ratios of dunites and harzburgites from the Dongqiao and Nagqu ophiolites vary from 0.1174 to 0.1316 and give Ten ages up to 1.43 Ga, also suggesting the existence of a Mesoproterozoic lithospheric mantle which has experienced mantle refertilization and later metasomatism caused by percolation of several generations of melts and/or fluids. We interpret the old mantle domains in the Bangong-Nujiang ophiolite belt as relics of ancient sub-continental lithospheric mantle (SCLM), which may have survived during the opening of the Bangong-Nujiang Tethyan ocean basin, and subsequently were incorporated into Mesozoic oceanic lithospheric mantle. (C) 2015 Elsevier B.V. All rights reserved.
关键词	PLATINUM-GROUP ELEMENTS SPINEL PERIDOTITE XENOLITHS HIGHLY SIDEROPHILE ELEMENTS SW TURKEY IMPLICATIONS MELT-ROCK INTERACTION ABYSSAL PERIDOTITES IN-SITU LITHOSPHERIC MANTLE TRACE-ELEMENT NEOTETHYAN OPHIOLITE
英文关键词	Mantle Re-Os isotopes; Tibet mantle evolution; Tethyan ophiolite ages; Bangong-Nujiang suture zone; Tibet
语种	英语
WOS研究方向	Geochemistry & Geophysics ; Mineralogy
WOS类目	Geochemistry & Geophysics ; Mineralogy
WOS记录号	WOS:000354342100003
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/258513
推荐引用方式 GB/T 7714	Huang, Qi-Shuai,Shi, Ren-Deng,O'Reilly, Suzanne Y.,et al. Re-Os isotopic constraints on the evolution of the Bangong-Nujiang Tethyan oceanic mantle, Central Tibet[J]. 中国科学院青藏高原研究所,2015,224.
APA	Huang, Qi-Shuai.,Shi, Ren-Deng.,O'Reilly, Suzanne Y..,Griffin, William L..,Zhang, Ming.,...&Zhang, Xiao-Ran.(2015).Re-Os isotopic constraints on the evolution of the Bangong-Nujiang Tethyan oceanic mantle, Central Tibet.LITHOS,224.
MLA	Huang, Qi-Shuai,et al."Re-Os isotopic constraints on the evolution of the Bangong-Nujiang Tethyan oceanic mantle, Central Tibet".LITHOS 224(2015).