Ar-40/Ar-39 Geochronology, geochemical characteristics and genesis of the Linzhou basic dikes, Tibet.

	Ar-40/Ar-39 Geochronology, geochemical characteristics and genesis of the Linzhou basic dikes, Tibet.
	Yue, YH ; Ding, L
刊名	ACTA PETROLOGICA SINICA
	2006-04-01
卷号	22 期号:4 页码:855-866
关键词	Linzhou basin Linzizong Group shoshonitic basic dike metasomatic lithospheric mantle roll-back and break-off of the oceanic lithosphere
ISSN号	1000-0569
文献子类	Article
英文摘要	This paper presents the geochemical and geochronological data of newly discovered shoshonitic basic dikes and some volcanics of the Linzizong Group in the Linzhou basin of Tibet. The shoshonitic dikes are characterized by low-Si (SiO2 45.42% similar to 48.32%), high-Mg (MgO 2.84% similar to 5.35%, averaged by 4.57%), high-K (K2O + Na2O 4.60% similar to 6.23% K2O/Na2O 0.71 similar to 1.18) relatively rich LREE and depleted HREE elements, weakly negative Eu anomaly (Eu/Eu* = 0.79 similar to 0.94, averaged by 0.83) very high contents of incompatible trace elements, negative Ta, Nb and Ti anomalies; initialized Sr-87/(86) Sr = 0.70487 similar to 0.70543, Nd-143/Nd-144 = 0.51266 similar to 0.51273, epsilon(Nd) = 0.5 similar to 1.8; delta O-18(V-SMOW) = 4, 8 parts per thousand similar to 7.6 parts per thousand. Trace-element compositions and isotopic characteristics suggest that these magmas originated from a metasomatic enriched mantle source, which is the subcontinental lithospheric mantle metasomatized by the components of the subducted oceanic crust/terrigenous sediments and asthenosphere mantle, and controlled by the roll-back and break-off of the subducted Neo-Tethys oceanic lithosphere and the upwelling and convection of the asthenosphere during the transition from oceanic to continental subduction, this magmatism indicates the wese-ease escensin-duris Paleocen-Eocene in the Gaydese is lock.
WOS关键词	TECTONIC EVOLUTION ; SOUTHERN TIBET ; VOLCANIC-ROCKS ; COLLISION ; INDIA ; MAGMATISM ; BASALTS ; MANTLE ; CHINA
WOS研究方向	Geology
语种	英语
出版者	SCIENCE CHINA PRESS
WOS记录号	WOS:000238367700009
内容类型	期刊论文
源URL	[http://ir.iggcas.ac.cn/handle/132A11/66538]
专题	中国科学院地质与地球物理研究所
通讯作者	Yue, YH
作者单位	1.Chinese Acad Sci, Inst Geol & Geophys, Beijing 100029, Peoples R China 2.Chinese Acad Sci, Inst Tibetan Plateau Res, Beijing 100085, Peoples R China
推荐引用方式 GB/T 7714	Yue, YH,Ding, L. Ar-40/Ar-39 Geochronology, geochemical characteristics and genesis of the Linzhou basic dikes, Tibet.[J]. ACTA PETROLOGICA SINICA,2006,22(4):855-866.
APA	Yue, YH,&Ding, L.(2006).Ar-40/Ar-39 Geochronology, geochemical characteristics and genesis of the Linzhou basic dikes, Tibet..ACTA PETROLOGICA SINICA,22(4),855-866.
MLA	Yue, YH,et al."Ar-40/Ar-39 Geochronology, geochemical characteristics and genesis of the Linzhou basic dikes, Tibet.".ACTA PETROLOGICA SINICA 22.4(2006):855-866.