Eclogite origin and timings in the North Qinling terrane, and their bearing on the amalgamation of the South and North China Blocks

doi:10.1111/j.1525-1314.2011.00955.x

	Eclogite origin and timings in the North Qinling terrane, and their bearing on the amalgamation of the South and North China Blocks
	Wang, H.1; Wu, Y. -B.1,2; Gao, S.1,2; Liu, X. -C.1; Gong, H. -J.3; Li, Q. -L.2; Li, X. -H.2; Yuan, H. -L.3
刊名	JOURNAL OF METAMORPHIC GEOLOGY
	2011-12-01
卷号	29 期号:9 页码:1019-1031
关键词	amalgamation eclogite North China Block Qinling South China Block zircon U-Pb age
ISSN号	0263-4929
DOI	10.1111/j.1525-1314.2011.00955.x
文献子类	Article
英文摘要	The amalgamation of South (SCB) and North China Blocks (NCB) along the Qinling-Dabie orogenic belt involved several stages of high pressure (HP)-ultra high pressure (UHP) metamorphism. The new discovery of UHP metamorphic rocks in the North Qinling (NQ) terrane can provide valuable information on this process. However, no precise age for the UHP metamorphism in the NQ terrane has been documented yet, and thus hinders deciphering of the evolution of the whole Qinling-Dabie-Sulu orogenic belt. This article reports an integrated study of U-Pb age, trace element, mineral inclusion and Hf isotope composition of zircon from an eclogite, a quartz vein and a schist in the NQ terrane. The zircon cores in the eclogite are characterized by oscillatory zoning or weak zoning, high Th/U and Lu-176/Hf-177 ratios, pronounced Eu anomalies and steep heavy rare earth element (HREE) patterns. The zircon cores yield an age of 796 +/- 13 Ma, which is taken as the protolith formation age of the eclogite, and implies that the NQ terrane may belong to the SCB before it collided with the NCB. The epsilon(Hf)(t) values vary from) -11.3 to 3.2 and corresponding two-stage Hf model ages are 2402 to 1495 Ma, suggesting the protolith was derived from an enriched mantle. In contrast, the metamorphic zircon rims show no zoning or weak zoning, very low Th/U and Lu-176/Hf-177 ratios, insignificant Eu anomalies and flat HREE patterns. They contain inclusions of garnet, omphacite and phengite, suggesting that the metamorphic zircon formed under eclogite facies metamorphic conditions, and their weighted mean Pb-206/U-238 age of 485.9 +/- 3.8 Ma was interpreted to date the timing of the eclogite facies metamorphism. Zircon in the quartz vein is characterized by perfect euhedral habit, some oscillatory zoning, low Th/U ratios and variable HREE contents. It yields a weighted mean U-Pb age of 480.5 +/- 2.5 Ma, which registers the age of fluid activity during exhumation. Zircon in the schist is mostly detrital and U-Pb age peaks at c. 1950 to 1850, 1800 to 1600, 1560 to 1460 and 1400 to 1260 Ma with an oldest grain of 2517 Ma, also suggesting that the NQ terrane may have an affinity to the SCB. Accordingly, the amalgamation between the SCB and the NCB is a multistage process that spans c. 300 Myr, which includes: the formation of the Erlangping intra-oceanic arc zone onto the NCB before c. 490 Ma, the c. 485 Ma crustal subduction and UHP metamorphism of the NQ terrane, the c. 430 Ma arc-continent collision and granulite facies metamorphism, the 420 to 400 Ma extension and rifting in relation to the opening of the Palaeo-Tethyan ocean, the c. 310 Ma HP eclogite facies metamorphism of oceanic crust and associated continental basement, and the final 250 to 220 Ma continental subduction and HP-UHP metamorphism.
WOS关键词	U-PB AGE ; ULTRAHIGH-PRESSURE ECLOGITE ; SUBDUCTION-ZONE METAMORPHISM ; WESTERN DABIE MOUNTAINS ; HF-ISOTOPE COMPOSITIONS ; HUWAN SHEAR ZONE ; TRACE-ELEMENT ; OROGENIC BELT ; O-ISOTOPE ; CONTINENTAL COLLISION
WOS研究方向	Geology
语种	英语
出版者	WILEY-BLACKWELL
WOS记录号	WOS:000296462100006
资助机构	Chinese 973 project(2009CB825006) ; Chinese 973 project(2009CB825006) ; National Natural Science Foundation of China(40873043 ; National Natural Science Foundation of China(40873043 ; Chinese Geological Survey Bureau(SinoProbe-05-04 ; Chinese Geological Survey Bureau(SinoProbe-05-04 ; Ministry of Education of China(IRT0441 ; Ministry of Education of China(IRT0441 ; Basic Scientific Research of Central Colleges, China University of Geosciences (Wuhan) ; Basic Scientific Research of Central Colleges, China University of Geosciences (Wuhan) ; 90714010 ; 90714010 ; 1212011120162) ; 1212011120162) ; B07039 ; B07039 ; 40772042 ; 40772042 ; NCET-06-0659) ; NCET-06-0659) ; 40521001) ; 40521001) ; Chinese 973 project(2009CB825006) ; Chinese 973 project(2009CB825006) ; National Natural Science Foundation of China(40873043 ; National Natural Science Foundation of China(40873043 ; Chinese Geological Survey Bureau(SinoProbe-05-04 ; Chinese Geological Survey Bureau(SinoProbe-05-04 ; Ministry of Education of China(IRT0441 ; Ministry of Education of China(IRT0441 ; Basic Scientific Research of Central Colleges, China University of Geosciences (Wuhan) ; Basic Scientific Research of Central Colleges, China University of Geosciences (Wuhan) ; 90714010 ; 90714010 ; 1212011120162) ; 1212011120162) ; B07039 ; B07039 ; 40772042 ; 40772042 ; NCET-06-0659) ; NCET-06-0659) ; 40521001) ; 40521001) ; Chinese 973 project(2009CB825006) ; Chinese 973 project(2009CB825006) ; National Natural Science Foundation of China(40873043 ; National Natural Science Foundation of China(40873043 ; Chinese Geological Survey Bureau(SinoProbe-05-04 ; Chinese Geological Survey Bureau(SinoProbe-05-04 ; Ministry of Education of China(IRT0441 ; Ministry of Education of China(IRT0441 ; Basic Scientific Research of Central Colleges, China University of Geosciences (Wuhan) ; Basic Scientific Research of Central Colleges, China University of Geosciences (Wuhan) ; 90714010 ; 90714010 ; 1212011120162) ; 1212011120162) ; B07039 ; B07039 ; 40772042 ; 40772042 ; NCET-06-0659) ; NCET-06-0659) ; 40521001) ; 40521001) ; Chinese 973 project(2009CB825006) ; Chinese 973 project(2009CB825006) ; National Natural Science Foundation of China(40873043 ; National Natural Science Foundation of China(40873043 ; Chinese Geological Survey Bureau(SinoProbe-05-04 ; Chinese Geological Survey Bureau(SinoProbe-05-04 ; Ministry of Education of China(IRT0441 ; Ministry of Education of China(IRT0441 ; Basic Scientific Research of Central Colleges, China University of Geosciences (Wuhan) ; Basic Scientific Research of Central Colleges, China University of Geosciences (Wuhan) ; 90714010 ; 90714010 ; 1212011120162) ; 1212011120162) ; B07039 ; B07039 ; 40772042 ; 40772042 ; NCET-06-0659) ; NCET-06-0659) ; 40521001) ; 40521001)
内容类型	期刊论文
源URL	[http://ir.iggcas.ac.cn/handle/132A11/74128]
专题	中国科学院地质与地球物理研究所
通讯作者	Wang, H.
作者单位	1.China Univ Geosci, Fac Earth Sci, State Key Lab Geol Proc & Mineral Resources, Wuhan 430074, Peoples R China 2.Chinese Acad Sci, 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	Wang, H.,Wu, Y. -B.,Gao, S.,et al. Eclogite origin and timings in the North Qinling terrane, and their bearing on the amalgamation of the South and North China Blocks[J]. JOURNAL OF METAMORPHIC GEOLOGY,2011,29(9):1019-1031.
APA	Wang, H..,Wu, Y. -B..,Gao, S..,Liu, X. -C..,Gong, H. -J..,...&Yuan, H. -L..(2011).Eclogite origin and timings in the North Qinling terrane, and their bearing on the amalgamation of the South and North China Blocks.JOURNAL OF METAMORPHIC GEOLOGY,29(9),1019-1031.
MLA	Wang, H.,et al."Eclogite origin and timings in the North Qinling terrane, and their bearing on the amalgamation of the South and North China Blocks".JOURNAL OF METAMORPHIC GEOLOGY 29.9(2011):1019-1031.