Tectonic development from oceanic subduction to continental collision: Geochemical evidence from postcollisional mafic rocks in the Hong'an-Dabie orogens

doi:10.1016/j.gr.2013.12.005

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

	Tectonic development from oceanic subduction to continental collision: Geochemical evidence from postcollisional mafic rocks in the Hong'an-Dabie orogens
	Dai, Li-Qun 1; Zhao, Zi-Fu 1,2; Zheng, Yong-Fei 1
刊名	GONDWANA RESEARCH
	2015-04-01
卷号	27 期号:3 页码:1236-1254
关键词	Postcollisional Magmatism Mafic Igneous Rocks Slab-mantle Interaction Melt-peridotite Reaction Subduction Channel Processes
DOI	10.1016/j.gr.2013.12.005
文献子类	Article
英文摘要	Continental collision is generally developed from oceanic subduction to continental subduction. Recycling of both oceanic and continental crustal materials is expected to occur in the same subduction zone. This is demonstrated by an integrated study of major-trace elements and stable-radiogenic isotopes in postcollisional mafic igneous rocks from the Hong'an-Dabie orogens, east-central China. Mafic dykes in the Hong'an orogen exhibit OIB-like trace element distribution patterns, high Nb/U and TiO2/Al2O3 ratios, relatively depleted radiogenic isotope compositions with consistently high epsilon(Nd)(t) values of -1.8 to 4.5 and low initial Sr-87/Sr-86 ratios of 0.7040 to 0.7050. They are significantly different from mafic intrusives in the Dabie orogen that exhibit arc-like trace element distribution patterns, low Nb/U and TiO2/Al2O3 ratios, relatively enriched radiogenic isotope compositions with low epsilon(Nd)(t) values of -2.3 to -20.7 and high initial Sr-87/Sr-86 ratios of 0.7061 to 0.7114. In addition, whole-rock and zircon Hf isotope compositions are decoupled in the Hong'an mafic dykes but coupled in the Dabie mafic intrusives. Nevertheless, zircon O isotope compositions exhibit similar variations for the two occurrences of mafic rocks. These observations are interpreted as indicating significant differences in the nature of mantle sources between the Hong'an and Dabie mafic rocks. Two types of melt-peridotite reaction are assumed to occur in oceanic and continental subduction channels, respectively, during continental collision. Reaction of juvenile subcontinental lithospheric mantle (SCLM) peridotite with felsic melt derived from subducting oceanic basalt and sediment before continental subduction would generate the mantle source for the Hong'an mafic dykes, whereas reaction of ancient SCLM peridotite with felsic melt from subducting continental crust would generate the mantle source for the Dabie mafic intrusives. While such contrasting types of melt-peridotite reaction at the slab-mantle interface are responsible for the systematic differences in the geochemical compositions of mantle sources, the incorporation of crust-derived felsic melts into the mantle wedge result in the similar lithology of non-peridotite such as pyroxenite and hornblendite. Therefore, the two types of slab-mantle interaction record the tectonic transition from oceanic subduction to continental subduction in the course of continental collision. The nature of slab-mantle interaction in subduction channel is a key to the origin of mantle sources for postcollisional mafic igneous rocks in continental collision orogens. (C) 2013 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.
WOS关键词	ZIRCON U-PB ; ULTRAHIGH-PRESSURE METAMORPHISM ; CRUST-MANTLE INTERACTION ; EARLY CRETACEOUS GRANITOIDS ; HF ISOTOPIC COMPOSITIONS ; MIDOCEAN RIDGE BASALT ; NORTH CHINA CRATON ; EAST-CENTRAL CHINA ; HUWAN SHEAR ZONE ; LITHOSPHERIC MANTLE
WOS研究方向	Geology
语种	英语
WOS记录号	WOS:000350918800021
资助机构	Natural Science Foundation of China(41125012 ; Natural Science Foundation of China(41125012 ; Fundamental Research Funds for the Central Universities(WK2080000054 ; Fundamental Research Funds for the Central Universities(WK2080000054 ; 41221062 ; 41221062 ; WK2080000032) ; WK2080000032) ; 41073025) ; 41073025) ; Natural Science Foundation of China(41125012 ; Natural Science Foundation of China(41125012 ; Fundamental Research Funds for the Central Universities(WK2080000054 ; Fundamental Research Funds for the Central Universities(WK2080000054 ; 41221062 ; 41221062 ; WK2080000032) ; WK2080000032) ; 41073025) ; 41073025)
内容类型	期刊论文
源URL	[http://ir.iggcas.ac.cn/handle/132A11/62565]
专题	地质与地球物理研究所_岩石圈演化国家重点实验室
作者单位	1.Univ Sci & Technol China, Sch Earth & Space Sci, CAS Key Lab Crust Mantle Mat & Environm, Hefei 230026, Peoples R China 2.Inst Geol & Geophys, State Key Lab Lithospher Evolut, Beijing 100029, Peoples R China
推荐引用方式 GB/T 7714	Dai, Li-Qun,Zhao, Zi-Fu,Zheng, Yong-Fei. Tectonic development from oceanic subduction to continental collision: Geochemical evidence from postcollisional mafic rocks in the Hong'an-Dabie orogens[J]. GONDWANA RESEARCH,2015,27(3):1236-1254.
APA	Dai, Li-Qun,Zhao, Zi-Fu,&Zheng, Yong-Fei.(2015).Tectonic development from oceanic subduction to continental collision: Geochemical evidence from postcollisional mafic rocks in the Hong'an-Dabie orogens.GONDWANA RESEARCH,27(3),1236-1254.
MLA	Dai, Li-Qun,et al."Tectonic development from oceanic subduction to continental collision: Geochemical evidence from postcollisional mafic rocks in the Hong'an-Dabie orogens".GONDWANA RESEARCH 27.3(2015):1236-1254.