Petrogenesis of late Early Oligocene trachytes in central Qiangtang Block, Tibetan Plateau: crustal melting during lithospheric delamination?

doi:10.1080/00206814.2019.1597391

CORC > 地质与地球物理研究所 > 中国科学院地质与地球物理研究所 > 岩石圈演化国家重点实验室

	Petrogenesis of late Early Oligocene trachytes in central Qiangtang Block, Tibetan Plateau: crustal melting during lithospheric delamination?
	Ou, Quan 1,2; Wang, Qiang 2,3,4; Zhang, Chunfu 5; Zhang, Hai-Xiang 2; Hao, Lu-Lu 2; Yang, Jin-Hui 6; Lai, Jian-Qing 1; Dan, Wei 2; Jiang, Zi-Qi 2,7; Xia, Xiao-Ping 2
刊名	INTERNATIONAL GEOLOGY REVIEW
	2019-03-31
页码	18
关键词	Oligocene trachyte newly formed crust remelting Tibet
ISSN号	0020-6814
DOI	10.1080/00206814.2019.1597391
英文摘要	Late Early Oligocene mantle-derived potassium (K)-rich lavas occur widely in the Qiangtang Block, central Tibet. However, it remains ambiguous whether partial melting of crust beneath central Tibet occurred in the Oligocene. Here, we report the newly identified trachytes in the Gemuchaka area of central Qiangtang Block. Zircon U-Pb and biotite Ar-40-Ar-39 analyses suggest that they were erupted at ca. 30 Ma, coeval with other K-rich lavas in the central Qiangtang Block. They have relatively constant and high SiO2 (62.4-62.9 wt.%), Al2O3 (17.2-17.4 wt.%), K2O (6.0-6.1 wt. %), and Na2O (4.6-4.7 wt.%) contents. They are characterized by enrichments of light rare earth elements (LREEs) and large-ion lithophile elements (LILEs), and by depletions of heavy REEs (HREEs) and high field strength elements (HFSEs), with negligible Eu but clear negative Ta-Nb-Ti anomalies. They have low epsilon Nd(t) (-5.5 to -4.6) but high (Sr-87/Sr-86)i (0.7076 to 0.7077) values, with variable zircon epsilon Hf(t) (-5.78 to 0.92) and delta O-18 (6.51 to 8.54) values. Except for obviously higher SiO2 contents, the trachytes are geochemically similar to the K-rich rocks in Gemuchaka area. We suggest that the trachytes were probably generated by remelting of the K-rich lower crust, which was possibly formed by the underplating of enriched mantle-derived K-rich lavas during the delamination of the lower part of thickened lithospheric mantle. After the delamination, the upwelling asthenosphere provided heat for partial melting of the lithospheric mantle and newly-formed lower crust. Our study provides the first petrological evidence for the existence of late Early Oligocene crust-derived rocks in the Qiangtang Block.
资助项目	National Key R & D Program of China[2016YFC0600309] ; National Key R & D Program of China[2016YFC0600407] ; Chinese Academy of Sciences[XDA2007030402] ; Chinese Academy of Sciences[QYZDJ-SSW-DQC026] ; Key Science Program of Guangzhou City[201707020032] ; GIGCAS 135 project[135TP201601] ; State Key Laboratory of Isotope Geochemistry, Guangzhou Institute of Geochemistry, Chineese Academy of Sciences[SKLabIG-KF-18-05] ; National Natural Science Foundation of China[41630208] ; National Natural Science Foundation of China[41802048] ; National Natural Science Foundation of China[41802057] ; National Natural Science Foundation of China[91855215] ; China Postdoctoral Science Foundation[2017M622597]
WOS关键词	U-PB ; TRACE-ELEMENT ; VOLCANIC-ROCKS ; SOUTHERN QIANGTANG ; NORTHERN TIBET ; ZIRCON GEOCHRONOLOGY ; TECTONIC EVOLUTION ; CONTINENTAL-CRUST ; WORKING REFERENCE ; BENEATH TIBET
WOS研究方向	Geology
语种	英语
出版者	TAYLOR & FRANCIS INC
WOS记录号	WOS:000465673000001
资助机构	National Key R & D Program of China ; National Key R & D Program of China ; Chinese Academy of Sciences ; Chinese Academy of Sciences ; Key Science Program of Guangzhou City ; Key Science Program of Guangzhou City ; GIGCAS 135 project ; GIGCAS 135 project ; State Key Laboratory of Isotope Geochemistry, Guangzhou Institute of Geochemistry, Chineese Academy of Sciences ; State Key Laboratory of Isotope Geochemistry, Guangzhou Institute of Geochemistry, Chineese Academy of Sciences ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; China Postdoctoral Science Foundation ; China Postdoctoral Science Foundation ; National Key R & D Program of China ; National Key R & D Program of China ; Chinese Academy of Sciences ; Chinese Academy of Sciences ; Key Science Program of Guangzhou City ; Key Science Program of Guangzhou City ; GIGCAS 135 project ; GIGCAS 135 project ; State Key Laboratory of Isotope Geochemistry, Guangzhou Institute of Geochemistry, Chineese Academy of Sciences ; State Key Laboratory of Isotope Geochemistry, Guangzhou Institute of Geochemistry, Chineese Academy of Sciences ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; China Postdoctoral Science Foundation ; China Postdoctoral Science Foundation ; National Key R & D Program of China ; National Key R & D Program of China ; Chinese Academy of Sciences ; Chinese Academy of Sciences ; Key Science Program of Guangzhou City ; Key Science Program of Guangzhou City ; GIGCAS 135 project ; GIGCAS 135 project ; State Key Laboratory of Isotope Geochemistry, Guangzhou Institute of Geochemistry, Chineese Academy of Sciences ; State Key Laboratory of Isotope Geochemistry, Guangzhou Institute of Geochemistry, Chineese Academy of Sciences ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; China Postdoctoral Science Foundation ; China Postdoctoral Science Foundation ; National Key R & D Program of China ; National Key R & D Program of China ; Chinese Academy of Sciences ; Chinese Academy of Sciences ; Key Science Program of Guangzhou City ; Key Science Program of Guangzhou City ; GIGCAS 135 project ; GIGCAS 135 project ; State Key Laboratory of Isotope Geochemistry, Guangzhou Institute of Geochemistry, Chineese Academy of Sciences ; State Key Laboratory of Isotope Geochemistry, Guangzhou Institute of Geochemistry, Chineese Academy of Sciences ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; China Postdoctoral Science Foundation ; China Postdoctoral Science Foundation
内容类型	期刊论文
源URL	[http://ir.iggcas.ac.cn/handle/132A11/91381]
专题	地质与地球物理研究所_岩石圈演化国家重点实验室
通讯作者	Wang, Qiang; Zhang, Hai-Xiang
作者单位	1.Cent S Univ, Key Lab Metallogen Predict Nonferrous Met & Geol, Minist Educ, Sch Geosci & Infophys, Changsha, Hunan, Peoples R China 2.Chinese Acad Sci, Guangzhou Inst Geochem, State Key Lab Isotope Geochem, Guangzhou 510640, Guangdong, Peoples R China 3.CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing, Peoples R China 4.Univ Chinese Acad Sci, Beijing, Peoples R China 5.Ft Hays State Univ, Dept Geosci, Hays, KS 67601 USA 6.Chinese Acad Sci, Inst Geol & Geophys, Beijing, Peoples R China 7.Guilin Univ Technol, Sch Earth Sci, Guilin, Peoples R China
推荐引用方式 GB/T 7714	Ou, Quan,Wang, Qiang,Zhang, Chunfu,et al. Petrogenesis of late Early Oligocene trachytes in central Qiangtang Block, Tibetan Plateau: crustal melting during lithospheric delamination?[J]. INTERNATIONAL GEOLOGY REVIEW,2019:18.
APA	Ou, Quan.,Wang, Qiang.,Zhang, Chunfu.,Zhang, Hai-Xiang.,Hao, Lu-Lu.,...&Xia, Xiao-Ping.(2019).Petrogenesis of late Early Oligocene trachytes in central Qiangtang Block, Tibetan Plateau: crustal melting during lithospheric delamination?.INTERNATIONAL GEOLOGY REVIEW,18.
MLA	Ou, Quan,et al."Petrogenesis of late Early Oligocene trachytes in central Qiangtang Block, Tibetan Plateau: crustal melting during lithospheric delamination?".INTERNATIONAL GEOLOGY REVIEW (2019):18.