Syn-exhumation magmatism during continental collision: Evidence from alkaline intrusives of Triassic age in the Sulu orogen

doi:10.1016/j.chemgeo.2011.11.002

	Syn-exhumation magmatism during continental collision: Evidence from alkaline intrusives of Triassic age in the Sulu orogen
	Zhao, Zi-Fu 1; Zheng, Yong-Fei 1; Zhang, Juan 1,3; Dai, Li-Qun 1; Li, Qiuli 2; Liu, Xiaoming 3
刊名	CHEMICAL GEOLOGY
	2012-10-18
卷号	328 页码:70-88
关键词	Crust-mantle interaction Continental collision Syn-exhumation magmatism Alkaline rocks Orogenic lithospheric mantle
ISSN号	0009-2541
DOI	10.1016/j.chemgeo.2011.11.002
文献子类	Article
英文摘要	A combined study of zircon U-Pb ages, Lu-Hf isotopes, mineral 0 isotopes, whole-rock elements and Sr-Nd isotopes was carried out for alkaline intrusive rocks (including gabbro, syenite and granite) in the Sulu orogen. The results provide insights into crust-mantle interaction in the continental subduction zone. SIMS and LA-ICPMS zircon U-Pb dating yield Late Triassic ages of 201 +/- 2 to 212 +/- 1 Ma for their crystallization. These ages are younger than Middle Triassic ages for ultrahigh-pressure (UHP) metamorphism of country rocks, corresponding to syn-exhumation magmatism during continental collision. The alkaline rocks are characterized by the arc-like patterns of trace element distribution, with relative enrichment of LILE and LREE but relative depletion of HFSE. They have high initial Sr-87/Sr-86 ratios of 0.7064 to 0.7114 and highly negative epsilon(Nd)(t) values of -16.4 to -13.8 with two-stage Nd model ages of 2.11 to 2.33 Ga for whole-rock. Zircon Lu-Hf isotope analyses also show highly negative epsilon(Hf)(t) values of -20.9 +/- 0.5 to -14.1 +/- 0.9, with two-stage Hf model ages of 2.10 +/- 0.06 to 2.56 +/- 0.03 Ga. The zircon exhibits relatively consistent delta O-18 values of 5.6 to 6.2 parts per thousand, slightly higher than normal mantle values. The enrichment of radiogenic Sr-Nd-Hf isotopes in the gabbro indicates its origination from an isotopically enriched mantle source, whereas the arc-like pattern of trace element distribution for it suggests a fertile mantle source with enrichment of LILE and LREE. Thus, it is part of the orogenic lithospheric mantle that would be generated by underplate reaction of the subcontinental lithospheric mantle with hydrous felsic melts derived from the subducted continental crust during the Triassic continental collision. On the other hand, there are general similarities in trace element and radiogenic isotope characteristics between the syenite-granite and UHP metaigneous rocks in the Dabie-Sulu orogenic belt, suggesting its genetic link to the subducted continental crust itself. Therefore, the alkaline rocks are derived from partial melting of the orogenic lithospheric mantle and the subducted continental crust in the stage of exhumation. They provide a petrological record of recycling the subducted continental crust into mantle depths with consequent crust-mantle interaction during the continental collision. (C) 2011 Elsevier B.V. All rights reserved.
WOS关键词	PRESSURE METAMORPHIC ROCKS ; ZIRCON U-PB ; SR ISOTOPIC EVIDENCE ; SUBDUCTION-ZONE METAMORPHISM ; CRUST-MANTLE INTERACTION ; TRACE-ELEMENT FRACTIONATION ; HF GARNET GEOCHRONOLOGY ; NORTHERN DABIE COMPLEX ; CENTRAL-EASTERN CHINA ; ULTRAHIGH-PRESSURE
WOS研究方向	Geochemistry & Geophysics
语种	英语
出版者	ELSEVIER SCIENCE BV
WOS记录号	WOS:000310124900004
资助机构	Chinese Academy of Sciences(KZCX2-YW-QN513) ; Chinese Academy of Sciences(KZCX2-YW-QN513) ; Chinese Ministry of Science and Technology(2009CB825004) ; Chinese Ministry of Science and Technology(2009CB825004) ; Natural Science Foundation of China(41125012 ; Natural Science Foundation of China(41125012 ; Chinese Universities Scientific Fund(WK2080000032) ; Chinese Universities Scientific Fund(WK2080000032) ; 40921002 ; 40921002 ; 41073025) ; 41073025) ; Chinese Academy of Sciences(KZCX2-YW-QN513) ; Chinese Academy of Sciences(KZCX2-YW-QN513) ; Chinese Ministry of Science and Technology(2009CB825004) ; Chinese Ministry of Science and Technology(2009CB825004) ; Natural Science Foundation of China(41125012 ; Natural Science Foundation of China(41125012 ; Chinese Universities Scientific Fund(WK2080000032) ; Chinese Universities Scientific Fund(WK2080000032) ; 40921002 ; 40921002 ; 41073025) ; 41073025) ; Chinese Academy of Sciences(KZCX2-YW-QN513) ; Chinese Academy of Sciences(KZCX2-YW-QN513) ; Chinese Ministry of Science and Technology(2009CB825004) ; Chinese Ministry of Science and Technology(2009CB825004) ; Natural Science Foundation of China(41125012 ; Natural Science Foundation of China(41125012 ; Chinese Universities Scientific Fund(WK2080000032) ; Chinese Universities Scientific Fund(WK2080000032) ; 40921002 ; 40921002 ; 41073025) ; 41073025) ; Chinese Academy of Sciences(KZCX2-YW-QN513) ; Chinese Academy of Sciences(KZCX2-YW-QN513) ; Chinese Ministry of Science and Technology(2009CB825004) ; Chinese Ministry of Science and Technology(2009CB825004) ; Natural Science Foundation of China(41125012 ; Natural Science Foundation of China(41125012 ; Chinese Universities Scientific Fund(WK2080000032) ; Chinese Universities Scientific Fund(WK2080000032) ; 40921002 ; 40921002 ; 41073025) ; 41073025)
内容类型	期刊论文
源URL	[http://ir.iggcas.ac.cn/handle/132A11/84642]
专题	中国科学院地质与地球物理研究所
通讯作者	Zhao, Zi-Fu
作者单位	1.Univ Sci & Technol China, CAS Key Lab Crust Mantle Mat & Environm, Dept Geochem & Environm Sci, Sch Earth & Space Sci, Hefei 230026, Peoples R China 2.Inst Geol & Geophys, State Key Lab Lithospher Evolut, Beijing 100029, Peoples R China 3.NW Univ Xian, Dept Geol, State Key Lab Continental Dynam, Xian 710069, Peoples R China
推荐引用方式 GB/T 7714	Zhao, Zi-Fu,Zheng, Yong-Fei,Zhang, Juan,et al. Syn-exhumation magmatism during continental collision: Evidence from alkaline intrusives of Triassic age in the Sulu orogen[J]. CHEMICAL GEOLOGY,2012,328:70-88.
APA	Zhao, Zi-Fu,Zheng, Yong-Fei,Zhang, Juan,Dai, Li-Qun,Li, Qiuli,&Liu, Xiaoming.(2012).Syn-exhumation magmatism during continental collision: Evidence from alkaline intrusives of Triassic age in the Sulu orogen.CHEMICAL GEOLOGY,328,70-88.
MLA	Zhao, Zi-Fu,et al."Syn-exhumation magmatism during continental collision: Evidence from alkaline intrusives of Triassic age in the Sulu orogen".CHEMICAL GEOLOGY 328(2012):70-88.