Geochronological and geochemical results from Mesozoic basalts in southern South China Block support the flat-slab subduction model

doi:10.1016/j.lithos.2011.11.022

	Geochronological and geochemical results from Mesozoic basalts in southern South China Block support the flat-slab subduction model
	Meng, Lifeng 1,2,3,4; Li, Zheng-Xiang 1,2,3; Chen, Hanlin 3,4; Li, Xian-Hua 5; Wang, Xuan-Ce 1,2,5,6
刊名	LITHOS
	2012-02-01
卷号	132 页码:127-140
关键词	South China Mesozoic Geochronology Geochemistry Tectonics Basalt Magmatism Flat-slab subduction Foundering
ISSN号	0024-4937
DOI	10.1016/j.lithos.2011.11.022
文献子类	Article
英文摘要	The debate on the Mesozoic tectonics of the South China Block (SCB), featuring a broad orogenic belt and a large continental magmatic province, has been rejuvenated in the past years. There are a number of competing tectonic models, each predicting different time, space, and compositional evolutional trends for the Mesozoic igneous rocks, including sporadic basalts. In this paper, we report high precision Ar-40/Ar-39 ages and geochemical and Sr-Nd isotopic data for basaltic rocks in central-eastern SCB. These results, together with a data compilation, indicate three evolutionary stages for the basalts. Stage 1 (195-160 Ma) basalts occur only in inland SCB. They exhibit low initial Sr-87/Sr-86 ratios (0.7038 to 0.7078), high epsilon Nd(t) values (-1.5 to 6.0) and ocean island basalt (OIB)-like geochemical characteristics such as low La/Nb ratios (0.6 to 1.4), implying negligible to minor lithosphere contamination. Stage 2 (160-110 Ma) basalts, mostly from the same inland region with minor occurrence closer to the coast, are characterized by variable initial Sr-87/Sr-86 ratios (0.7053 to 0.7102), epsilon Nd(t) values (-6.0 to 5.0) and low La/Nb ratios (0.9 to 1.8), indicating an enhanced asthenosphere-lithosphere interaction. Stage 3 (110 to <= 80 Ma) basalts can be further divided into two subgroups based on their geographic and geochemical variations. Basalts in the coastal regions are characterized by low epsilon Nd(t) values (-8.1 to 3.7) and variably high La/Nb ratios (up to 4.8) indicating a strong arc signature. On the other hand, basalts in the inland regions have high epsilon Nd(t) values (-1.9 to 6.8) and low La/Nb ratios (0.6 to 1.2) that are similar to the stage 1 basalts. We interpret these features as results of geodynamics processes related to the break-up, foundering and retreating of an early Mesozoic flat-subducted oceanic slab. (C) 2011 Elsevier B.V. All rights reserved.
WOS关键词	U-PB ZIRCON ; SE CHINA ; TECTONIC SIGNIFICANCE ; ISOTOPIC CONSTRAINTS ; VOLCANIC-ROCKS ; SOUTHEASTERN CHINA ; HUNAN PROVINCE ; EASTERN CHINA ; FLOOD BASALTS ; YANGTZE BLOCK
WOS研究方向	Geochemistry & Geophysics ; Mineralogy
语种	英语
出版者	ELSEVIER SCIENCE BV
WOS记录号	WOS:000301219900009
资助机构	National Basic Research Program of China(2007CB411706-04-2) ; National Basic Research Program of China(2007CB411706-04-2) ; Chinese National Natural Science Foundation(40728002) ; Chinese National Natural Science Foundation(40728002) ; Australian Research Council(DP110104799) ; Australian Research Council(DP110104799) ; National Basic Research Program of China(2007CB411706-04-2) ; National Basic Research Program of China(2007CB411706-04-2) ; Chinese National Natural Science Foundation(40728002) ; Chinese National Natural Science Foundation(40728002) ; Australian Research Council(DP110104799) ; Australian Research Council(DP110104799) ; National Basic Research Program of China(2007CB411706-04-2) ; National Basic Research Program of China(2007CB411706-04-2) ; Chinese National Natural Science Foundation(40728002) ; Chinese National Natural Science Foundation(40728002) ; Australian Research Council(DP110104799) ; Australian Research Council(DP110104799) ; National Basic Research Program of China(2007CB411706-04-2) ; National Basic Research Program of China(2007CB411706-04-2) ; Chinese National Natural Science Foundation(40728002) ; Chinese National Natural Science Foundation(40728002) ; Australian Research Council(DP110104799) ; Australian Research Council(DP110104799)
内容类型	期刊论文
源URL	[http://ir.iggcas.ac.cn/handle/132A11/84718]
专题	中国科学院地质与地球物理研究所
通讯作者	Li, Zheng-Xiang
作者单位	1.Curtin Univ, Dept Appl Geol, Inst Geosci Res TIGeR, Perth, WA 6845, Australia 2.Curtin Univ, ARC Ctr Excellence Core Crust Fluid Syst CCFS, Perth, WA 6845, Australia 3.Zhejiang Univ, Dept Earth Sci, Hangzhou 310027, Peoples R China 4.Minist Educ, Struct Res Ctr Oil & Gas Bearing Basin, Hangzhou 310027, Peoples R China 5.Chinese Acad Sci, Inst Geol & Geophys, State Key Lab Lithospher Evolut, Beijing 10029, Peoples R China 6.Univ Western Australia, Sch Earth & Environm, Nedlands, WA 6009, Australia
推荐引用方式 GB/T 7714	Meng, Lifeng,Li, Zheng-Xiang,Chen, Hanlin,et al. Geochronological and geochemical results from Mesozoic basalts in southern South China Block support the flat-slab subduction model[J]. LITHOS,2012,132:127-140.
APA	Meng, Lifeng,Li, Zheng-Xiang,Chen, Hanlin,Li, Xian-Hua,&Wang, Xuan-Ce.(2012).Geochronological and geochemical results from Mesozoic basalts in southern South China Block support the flat-slab subduction model.LITHOS,132,127-140.
MLA	Meng, Lifeng,et al."Geochronological and geochemical results from Mesozoic basalts in southern South China Block support the flat-slab subduction model".LITHOS 132(2012):127-140.