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DOI	10.1007/s11434-012-5384-8
	Os isotopic evidence for a carbonaceous chondritic mantle source for the Nagqu ophiolite from Tibet and its implications
	Huang QiShuai; Shi RenDeng; Liu DeLiang; Zhang XiaoRan; Fan ShuaiQuan; Ding Lin
通讯作者	Huang, QS (通讯作者)
发表日期	2013
ISSN	1001-6538
起始页码	92
结束页码	98
卷号	58 期号:1
英文摘要	Early-crystallizing chromian spinel (Cr-spinel) in the Nagqu ophiolite has high Os and low Re contents, and it is resistant to alteration during serpentinization, weathering and metamorphism. The chemical composition of primitive magma is preserved in Cr-spinel, which makes it suitable for determining the initial Os-isotope composition of the mantle source. This study presents Cr-spinel Os isotopes and zircon U-Pb ages for cumulate dunite and gabbro, respectively, in the same cumulate section of the ophiolite at Nagqu in Tibet. The results shed light on the formation and evolution of lithospheric mantle. The Nagqu ophiolite is located in the central part of the Bangong-Nujiang suture zone. It is a remnant of the Neotethyan oceanic crust, and contains cumulate dunite and gabbro. Zircon from the gabbro yielded a weighted mean Pb-206/U-238 age of 183.7 +/- 1 Ma. Cr-spinel exhibits gamma (Os) values of -0.2 to -0.3, suggesting that the mantle source for the dunite is similar to that of carbonaceous chondrites. Thus, the Tibetan lithosphere is primarily a relic of Tethyan oceanic lithosphere, which has formed by the transformation of the normal asthenospheric mantle in the Mesozoic. This is the first study to combine the spinel Os isotopes with accurate zircon U-Pb ages to constrain the geochemical characteristics of the mantle source for the ophiolite.
关键词	PRIMITIVE UPPER-MANTLE LARGE IGNEOUS PROVINCE BENEATH OCEAN RIDGES LITHOSPHERIC MANTLE U-PB ABYSSAL PERIDOTITES MASS-SPECTROMETRY NORTHERN TIBET INDIAN-OCEAN SIDEROPHILE ELEMENTS
英文关键词	Re-Os isotopes; spinel; ophiolite; Nagqu; Tibet
语种	英语
WOS研究方向	Science & Technology - Other Topics
WOS类目	Multidisciplinary Sciences
WOS记录号	WOS:000313736600015
来源期刊	CHINESE SCIENCE BULLETIN
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/258098
推荐引用方式 GB/T 7714	Huang QiShuai,Shi RenDeng,Liu DeLiang,et al. Os isotopic evidence for a carbonaceous chondritic mantle source for the Nagqu ophiolite from Tibet and its implications[J]. 中国科学院青藏高原研究所,2013,58(1).
APA	Huang QiShuai,Shi RenDeng,Liu DeLiang,Zhang XiaoRan,Fan ShuaiQuan,&Ding Lin.(2013).Os isotopic evidence for a carbonaceous chondritic mantle source for the Nagqu ophiolite from Tibet and its implications.CHINESE SCIENCE BULLETIN,58(1).
MLA	Huang QiShuai,et al."Os isotopic evidence for a carbonaceous chondritic mantle source for the Nagqu ophiolite from Tibet and its implications".CHINESE SCIENCE BULLETIN 58.1(2013).