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DOI	10.1016/j.jseaes.2023.105763
	Zircon xenocryst geochronology and implications for the Lhasa terrane evolution: Insights from Cenozoic volcanic rocks (Coqen, Tibet)
	Zhang, Yu-Fei; Xu, Bo; Hou, Zeng-Qian; Zhao, Yi; Wang, Zi-Xuan; Shen, Jia-Qi; Kou, Guan-Yu; Yu, Jia-Xing; Li, En-Qi
发表日期	2023
ISSN	1367-9120
EISSN	1878-5786
卷号	255
英文摘要	The Cenozoic volcanic rocks of Coqen are located in the western central Lhasa subterrane, where knowledge of the regional lithospheric architecture and related magmatic processes is still lacking. To address this issue, we used in situ U-Pb dating, Lu-Hf isotopic and mineral inclusion analysis in zircon xenocrysts among trachyandesite. These zircons from volcanic samples yielded wide U-Pb ages from 18 Ma to 2424 Ma, showing three significant age peaks at - 246 Ma, 193 Ma, and the most intense one at 128 Ma, which represent three major magmatic processes that developed in the area. The earliest zircon dates suggest the age of volcanic eruption in the Coqen area was not earlier than 18 Ma. Zircon xenocrysts trace elements data point to the continental crust origin of central Lhasa subterrane. We provide the evidence for evolutive magmatism of the Lhasa terrane by calculating & UDelta;FMQ, and show that the oxygen fugacity goes from reduced to oxidized (Cambrian to Miocene). The very low & epsilon;Hf(t) indicate a long-term magmatic event sequence, with the Zenong Group having the most vigorous magmatic activity. The old U-Pb ages and TDMC confirmed that an ancient basement of the Precambrian exist in the middle Lhasa terrane. Our work also restores the tectonic and crustal thickness evolutionary process of Coqen area even entire Lhasa terrane. In the back of a series of thickening and thinning processes, the Tibetan crust drastically thickened at - 54 Ma, and gradually created what is now believed to be the thickest crust in the world.
关键词	Central Lhasa subterrane Zircon xenocrysts U -Pb geochronology Geochemistry Magmatic activities Lithospheric architecture
英文关键词	U-PB AGE; IGNEOUS ROCKS; TECTONIC EVOLUTION; CONTINENTAL-CRUST; DETRITAL ZIRCONS; DEEP CRUST; CONSTRAINTS; HF; MANTLE; QIANGTANG
WOS研究方向	Geosciences, Multidisciplinary
WOS记录号	WOS:001032474500001
来源期刊	JOURNAL OF ASIAN EARTH SCIENCES
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/283464
作者单位	China University of Geosciences - Beijing; China Geological Survey; Chinese Academy of Geological Sciences; China Geological Survey; Chinese Academy of Geological Sciences; Institute of Geology, Chinese Academy of Geological Sciences; China University of Geosciences - Beijing
推荐引用方式 GB/T 7714	Zhang, Yu-Fei,Xu, Bo,Hou, Zeng-Qian,et al. Zircon xenocryst geochronology and implications for the Lhasa terrane evolution: Insights from Cenozoic volcanic rocks (Coqen, Tibet)[J],2023,255.
APA	Zhang, Yu-Fei.,Xu, Bo.,Hou, Zeng-Qian.,Zhao, Yi.,Wang, Zi-Xuan.,...&Li, En-Qi.(2023).Zircon xenocryst geochronology and implications for the Lhasa terrane evolution: Insights from Cenozoic volcanic rocks (Coqen, Tibet).JOURNAL OF ASIAN EARTH SCIENCES,255.
MLA	Zhang, Yu-Fei,et al."Zircon xenocryst geochronology and implications for the Lhasa terrane evolution: Insights from Cenozoic volcanic rocks (Coqen, Tibet)".JOURNAL OF ASIAN EARTH SCIENCES 255(2023).