Early Cretaceous intermediate-mafic dykes in the Dabie orogen, eastern China: Petrogenesis and implications for crust-mantle interaction

doi:10.1016/j.lithos.2012.06.030

	Early Cretaceous intermediate-mafic dykes in the Dabie orogen, eastern China: Petrogenesis and implications for crust-mantle interaction
	Xu, Haijin 1,2; Ma, Changqian 1,2; Song, Yanru 3; Zhang, Junfeng 1,2; Ye, Kai 4
刊名	LITHOS
	2012-12-01
卷号	154 页码:83-99
关键词	Intermediate-mafic dyke Geochemistry Sr-Nd-Hf isotopes Crust-mantle interaction Dabie orogen
ISSN号	0024-4937
DOI	10.1016/j.lithos.2012.06.030
文献子类	Article
英文摘要	Early Cretaceous intermediate-mafic dykes in the Dabie orogen, eastern China, provide an opportunity to examine the process of crust-mantle interaction caused by foundering of eclogitized lower continental crust (LCC) into underlying mantle. Chronological, geochemical and Sr-Nd-Hf isotopic analyses were carried out on the intermediate-mafic dykes. SHRIMP zircon U-Pb dating yields emplacement ages of 126 +/- 3 Ma and 127 +/- 2 Ma for the intermediate-mafic dykes. The dykes have wide ranges of SiO2 (44.9-61.4 wt.%), MgO (2.6-9.1 wt.%; Mg-#=41.3-61.7) Ni (6.9-135.0 ppm), and Cr (3.9-340.3 ppm) contents. They are enriched in light rare earth elements (LREE) and large ion lithophile elements (LILE, e.g., Ba, K, and Pb), and depleted in heavy rare earth elements (HREE) and high field strength elements (HFSE, e.g., Nb, Ta, and Ti) and Sr with weak negative Eu anomalies (Eu/Eu* = 0.74-1.04). Meanwhile, the dykes show relatively high whole-rock initial Sr-87/Sr-86 ratios (0.7056-0.7094) and negative epsilon(Nd)(t) values (-19.9 to -14.2), and display low zircon Hf-176/Hf-177 ratios (0.28193-028208) with negative epsilon(Hf)(t) values (-26.8 to -202). Such typical "continental" geochemical features do not result from crustal contamination, but reflect an enriched mantle source resulting from hybridization with the foundered eclogitized LCC We propose that the foundering of LCC led to the tectonic collapse of the Dabie orogen and the crust-mantle interaction beneath it during the Early Cretaceous. (C) 2012 Elsevier B.V. All rights reserved.
WOS关键词	LOWER CONTINENTAL-CRUST ; U-PB AGE ; ULTRAHIGH-PRESSURE METAMORPHISM ; SR-ISOTOPE EVIDENCE ; SULU OROGEN ; MESOZOIC GRANITOIDS ; TRACE-ELEMENT ; SOUTH CHINA ; NORTH DABIE ; O-ISOTOPE
WOS研究方向	Geochemistry & Geophysics ; Mineralogy
语种	英语
出版者	ELSEVIER SCIENCE BV
WOS记录号	WOS:000312684000006
资助机构	National Natural Science Foundation of China(41072046 ; National Natural Science Foundation of China(41072046 ; Fundamental Research Funds for the Central Universities, China University of Geosciences (Wuhan)(CUG120121) ; Fundamental Research Funds for the Central Universities, China University of Geosciences (Wuhan)(CUG120121) ; 40603002 ; 40603002 ; 90714005) ; 90714005) ; National Natural Science Foundation of China(41072046 ; National Natural Science Foundation of China(41072046 ; Fundamental Research Funds for the Central Universities, China University of Geosciences (Wuhan)(CUG120121) ; Fundamental Research Funds for the Central Universities, China University of Geosciences (Wuhan)(CUG120121) ; 40603002 ; 40603002 ; 90714005) ; 90714005) ; National Natural Science Foundation of China(41072046 ; National Natural Science Foundation of China(41072046 ; Fundamental Research Funds for the Central Universities, China University of Geosciences (Wuhan)(CUG120121) ; Fundamental Research Funds for the Central Universities, China University of Geosciences (Wuhan)(CUG120121) ; 40603002 ; 40603002 ; 90714005) ; 90714005) ; National Natural Science Foundation of China(41072046 ; National Natural Science Foundation of China(41072046 ; Fundamental Research Funds for the Central Universities, China University of Geosciences (Wuhan)(CUG120121) ; Fundamental Research Funds for the Central Universities, China University of Geosciences (Wuhan)(CUG120121) ; 40603002 ; 40603002 ; 90714005) ; 90714005)
内容类型	期刊论文
源URL	[http://ir.iggcas.ac.cn/handle/132A11/84740]
专题	中国科学院地质与地球物理研究所
通讯作者	Xu, Haijin
作者单位	1.China Univ Geosci, Fac Earth Sci, Wuhan 430074, Peoples R China 2.China Univ Geosci, State Key Lab Geol Proc & Mineral Resources, Wuhan 430074, Peoples R China 3.China Univ Geosci, Editorial Off Journal, Wuhan 430074, Peoples R China 4.Chinese Acad Sci, State Key Lab Lithospher Evolut, Inst Geol & Geophys, Beijing 100029, Peoples R China
推荐引用方式 GB/T 7714	Xu, Haijin,Ma, Changqian,Song, Yanru,et al. Early Cretaceous intermediate-mafic dykes in the Dabie orogen, eastern China: Petrogenesis and implications for crust-mantle interaction[J]. LITHOS,2012,154:83-99.
APA	Xu, Haijin,Ma, Changqian,Song, Yanru,Zhang, Junfeng,&Ye, Kai.(2012).Early Cretaceous intermediate-mafic dykes in the Dabie orogen, eastern China: Petrogenesis and implications for crust-mantle interaction.LITHOS,154,83-99.
MLA	Xu, Haijin,et al."Early Cretaceous intermediate-mafic dykes in the Dabie orogen, eastern China: Petrogenesis and implications for crust-mantle interaction".LITHOS 154(2012):83-99.