Triassic three-stage collision in the Paleo-Tethys: Constraints from magmatism in the Jiangda-Deqen-Weixi continental margin arc, SW China

doi:10.1016/j.gr.2013.07.023

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	Triassic three-stage collision in the Paleo-Tethys: Constraints from magmatism in the Jiangda-Deqen-Weixi continental margin arc, SW China
	Wang, Baodi 1; Wang, Liquan 1; Chen, Jianlin 2; Yin, Fuguang 1; Wang, Dongbing 1; Zhang, Wanping 1; Chen, Lingkang 3; Liu, Han 1
刊名	GONDWANA RESEARCH
	2014
卷号	26 期号:2 页码:475-491
关键词	Triassic bimodal volcanic rocks Slab break-off Collisional orogenesis Jiangda-Deqen-Weixi continental margin arc (DWCA) Paleo-Tethys
ISSN号	1342-937X
DOI	10.1016/j.gr.2013.07.023
英文摘要	Triassic volcanic rocks in the Jiangda-Deqen-Weixi continental margin arc (DWCA) in the Sanjiang area of SW China formed as a result of the closure of the Paleo-Tethys and associated continental collision, and are therefore important for reconstructing the evolution of the Paleo-Tethys. Representative samples of rhyolite and basalt from the Jijiading-Luchun-Yezhi area yield weighted mean Pb-206/U-238 ages of 245-249 Ma and 245 Ma, respectively, and exhibit the features of bimodal volcanic rocks. The mafic rocks are enriched in large ion lithophile elements (e.g., Rb, Ba, U), are depleted in high field strength elements (e.g., Nb,Ta, Ti), and have low epsilon(Nd)(t) values (-3.55 to -3.69) and high initial Sr-87/Sr-86 values (0.70788-0.70804). The mafic rocks were formed by partial melting of an enriched lithospheric mantle source that had been metasomatized by fluids derived from subducted sediments. The felsic rocks are characterized by high K2O (K2O/Na2O = 2.16-71.33) and A/CNK (>1.1), and low Mg# (20-45) and epsilon(Nd)(t) values (-9.61 to -10.66), with zircon epsilon(Hf)(t) values of -8.1 to -16.6. Their old Nd model ages are similar to those of ancient Yangtze basement, indicating that they formed by partial melting of this ancient crust as a result of underplating by basaltic magma. We suggest that the bimodal volcanic rocks in the DWCA formed in an extensional setting as a result of slab break-off during a margin of arc-continent collision. The present results, combined with previous data, reveal three stages of collision in the Paleo-Tethys: early collision convergence (similar to 255-250 Ma), syn-collision extension (249-237 Ma), and late collision orogenesis (236-212 Ma). (C) 2013 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.
学科主题	构造地质学
WOS关键词	SOUTHERN LANCANGJIANG ZONE ; YANGLA COPPER-DEPOSIT ; IN-SITU ANALYSIS ; U-PB AGES ; VOLCANIC-ROCKS ; SOUTHWEST CHINA ; TRACE-ELEMENTS ; HF ISOTOPES ; ICP-MS ; JINSHAJIANG OPHIOLITE
WOS研究方向	Geology
语种	英语
出版者	ELSEVIER SCIENCE BV
WOS记录号	WOS:000339037800006
内容类型	期刊论文
源URL	[http://119.78.100.197/handle/2HKVOGP0/40347]
专题	中国地质调查局成都地质调查中心
作者单位	1.Chengdu Inst Geol & Mineral Resources, Chengdu 610081, Peoples R China 2.China Geol Survey, Res Ctr Tibetan Plateau Geol, Chengdu 610081, Peoples R China 3.Chinese Acad Sci, Guangzhou Inst Geochem, State Key Lab Isotope Geochem, Guangzhou 510640, Guangdong, Peoples R China 4.Jiangxi Univ Sci & Technol, Fac Resource & Environm Engn, Ganzhou 341000, Peoples R China
推荐引用方式 GB/T 7714	Wang, Baodi,Wang, Liquan,Chen, Jianlin,et al. Triassic three-stage collision in the Paleo-Tethys: Constraints from magmatism in the Jiangda-Deqen-Weixi continental margin arc, SW China[J]. GONDWANA RESEARCH,2014,26(2):475-491.
APA	Wang, Baodi.,Wang, Liquan.,Chen, Jianlin.,Yin, Fuguang.,Wang, Dongbing.,...&Liu, Han.(2014).Triassic three-stage collision in the Paleo-Tethys: Constraints from magmatism in the Jiangda-Deqen-Weixi continental margin arc, SW China.GONDWANA RESEARCH,26(2),475-491.
MLA	Wang, Baodi,et al."Triassic three-stage collision in the Paleo-Tethys: Constraints from magmatism in the Jiangda-Deqen-Weixi continental margin arc, SW China".GONDWANA RESEARCH 26.2(2014):475-491.