Ordovician eclogites from the Chinese Beishan: implications for the tectonic evolution of the southern Altaids

doi:10.1111/j.1525-1314.2011.00942.x

	Ordovician eclogites from the Chinese Beishan: implications for the tectonic evolution of the southern Altaids
	Qu, J. F.1,2; Xiao, W. J.2; Windley, B. F.3; Han, C. M.2; Mao, Q. G.2; Ao, S. J.2; Zhang, J. E.2
刊名	JOURNAL OF METAMORPHIC GEOLOGY
	2011-10-01
卷号	29 期号:8 页码:803-820
关键词	Altaids Beishan Orogen Eclogite Ordovician P-t Path
ISSN号	0263-4929
DOI	10.1111/j.1525-1314.2011.00942.x
文献子类	Article
英文摘要	Numerous lenses of eclogite occur in a belt of augen orthogneisses in the Gubaoquan area in the southern Beishan orogen, an eastern extension of the Tianshan orogen. With detailed petrological data and phase relations, modelled in the system NCFMASHTO with THERMOCALC, a quantitative P-T path was estimated and defined a clockwise P-T path that showed a near isothermal decompression from eclogite facies (> 15.5 kbar, 700-800 (degrees)C, omphacite + garnet) to high-pressure granulite facies (12-14 kbar, 700-750 degrees C, clinopyroxene + sodic plagioclase symplectitic intergrowths around omphacite), low-pressure granulite facies (8-9.5 kbar, similar to 700 degrees C, orthopyroxene + clinopyroxene + plagioclase symplectites and coronas surrounding garnet) and amphibolite facies (5-7 kbar, 600-700 degrees C, hornblende + plagioclase symplectites). The major and trace elements and Sm-Nd isotopic data suggest that most of the Beishan eclogite samples had a protolith of oceanic crust with geochemical characteristics of an enriched or normal mid-ocean ridge basalt. The U-Pb dating of the Beishan eclogites indicates an Ordovician age of c. 467 Ma for the eclogite facies metamorphism. An (39)Ar/(40)Ar age of c. 430 Ma for biotite from the augen gneiss corresponds to the time of retrograde metamorphism. The combined data from geological setting, bulk composition, clockwise P-T path and geochronology support a model in which the Beishan eclogites started as oceanic crust in the Palaeoasian Ocean, which was subducted to eclogite depths in the Ordovician and exhumed in the Silurian. The eclogite-bearing gneiss belt marks the position of a high-pressure Ordovician suture zone, and the calculated clockwise P-T path defines the progression from subduction to exhumation.
WOS关键词	MINERAL EQUILIBRIA CALCULATIONS ; UHP METAMORPHIC BELT ; ASIAN OROGENIC BELT ; HIGH-PRESSURE ROCKS ; NW CHINA ; U-PB ; SYSTEM K2O-FEO-MGO-AL2O3-SIO2-H2O-TIO2-FE2O3 ; PALEOZOIC ACCRETIONARY ; COLLISIONAL TECTONICS ; RETROGRADED ECLOGITES
WOS研究方向	Geology
语种	英语
出版者	WILEY-BLACKWELL
WOS记录号	WOS:000294872200001
资助机构	Chinese 973 Program(2007CB411307) ; Chinese 973 Program(2007CB411307) ; Chinese 973 Program(2007CB411307) ; Chinese 973 Program(2007CB411307) ; National Natural Science Foundation of China(40872058 ; National Natural Science Foundation of China(40872058 ; National Natural Science Foundation of China(40872058 ; National Natural Science Foundation of China(40872058 ; National 305 Projects(2011BAB06B04 ; National 305 Projects(2011BAB06B04 ; National 305 Projects(2011BAB06B04 ; National 305 Projects(2011BAB06B04 ; 40725009 ; 40725009 ; 40725009 ; 40725009 ; 2007BAB25B04) ; 2007BAB25B04) ; 2007BAB25B04) ; 2007BAB25B04) ; 40523003 ; 40523003 ; 40523003 ; 40523003 ; 40973036) ; 40973036) ; 40973036) ; 40973036) ; Chinese 973 Program(2007CB411307) ; Chinese 973 Program(2007CB411307) ; Chinese 973 Program(2007CB411307) ; Chinese 973 Program(2007CB411307) ; National Natural Science Foundation of China(40872058 ; National Natural Science Foundation of China(40872058 ; National Natural Science Foundation of China(40872058 ; National Natural Science Foundation of China(40872058 ; National 305 Projects(2011BAB06B04 ; National 305 Projects(2011BAB06B04 ; National 305 Projects(2011BAB06B04 ; National 305 Projects(2011BAB06B04 ; 40725009 ; 40725009 ; 40725009 ; 40725009 ; 2007BAB25B04) ; 2007BAB25B04) ; 2007BAB25B04) ; 2007BAB25B04) ; 40523003 ; 40523003 ; 40523003 ; 40523003 ; 40973036) ; 40973036) ; 40973036) ; 40973036) ; Chinese 973 Program(2007CB411307) ; Chinese 973 Program(2007CB411307) ; Chinese 973 Program(2007CB411307) ; Chinese 973 Program(2007CB411307) ; National Natural Science Foundation of China(40872058 ; National Natural Science Foundation of China(40872058 ; National Natural Science Foundation of China(40872058 ; National Natural Science Foundation of China(40872058 ; National 305 Projects(2011BAB06B04 ; National 305 Projects(2011BAB06B04 ; National 305 Projects(2011BAB06B04 ; National 305 Projects(2011BAB06B04 ; 40725009 ; 40725009 ; 40725009 ; 40725009 ; 2007BAB25B04) ; 2007BAB25B04) ; 2007BAB25B04) ; 2007BAB25B04) ; 40523003 ; 40523003 ; 40523003 ; 40523003 ; 40973036) ; 40973036) ; 40973036) ; 40973036) ; Chinese 973 Program(2007CB411307) ; Chinese 973 Program(2007CB411307) ; Chinese 973 Program(2007CB411307) ; Chinese 973 Program(2007CB411307) ; National Natural Science Foundation of China(40872058 ; National Natural Science Foundation of China(40872058 ; National Natural Science Foundation of China(40872058 ; National Natural Science Foundation of China(40872058 ; National 305 Projects(2011BAB06B04 ; National 305 Projects(2011BAB06B04 ; National 305 Projects(2011BAB06B04 ; National 305 Projects(2011BAB06B04 ; 40725009 ; 40725009 ; 40725009 ; 40725009 ; 2007BAB25B04) ; 2007BAB25B04) ; 2007BAB25B04) ; 2007BAB25B04) ; 40523003 ; 40523003 ; 40523003 ; 40523003 ; 40973036) ; 40973036) ; 40973036) ; 40973036)
内容类型	期刊论文
源URL	[http://ir.iggcas.ac.cn/handle/132A11/73554]
专题	中国科学院地质与地球物理研究所
通讯作者	Qu, J. F.
作者单位	1.Chinese Acad Geol Sci, Inst Geol, Beijing 100037, Peoples R China 2.Chinese Acad Sci, Inst Geol & Geophys, State Key Lab Lithospher Evolut, Beijing 100029, Peoples R China 3.Univ Leicester, Dept Geol, Leicester LE1 7RH, Leics, England
推荐引用方式 GB/T 7714	Qu, J. F.,Xiao, W. J.,Windley, B. F.,et al. Ordovician eclogites from the Chinese Beishan: implications for the tectonic evolution of the southern Altaids[J]. JOURNAL OF METAMORPHIC GEOLOGY,2011,29(8):803-820.
APA	Qu, J. F..,Xiao, W. J..,Windley, B. F..,Han, C. M..,Mao, Q. G..,...&Zhang, J. E..(2011).Ordovician eclogites from the Chinese Beishan: implications for the tectonic evolution of the southern Altaids.JOURNAL OF METAMORPHIC GEOLOGY,29(8),803-820.
MLA	Qu, J. F.,et al."Ordovician eclogites from the Chinese Beishan: implications for the tectonic evolution of the southern Altaids".JOURNAL OF METAMORPHIC GEOLOGY 29.8(2011):803-820.