The Aoyougou mafic-ultramafic complex in the North Qilian Mountains,;northwest China: A possible Middle Proterozoic ophiolite along the;southern margin of the North China craton

	The Aoyougou mafic-ultramafic complex in the North Qilian Mountains,;northwest China: A possible Middle Proterozoic ophiolite along the;southern margin of the North China craton
	Zhang, ZC 6; Mao, JW ; Robinson, PT ; Zhou, MF ; Zuo, GC ; Yang, JM ; Wang, ZL ; Zhang, ZH
刊名	INTERNATIONAL GEOLOGY REVIEW
	2003
卷号	45 期号:9 页码:841-856
ISSN号	0020-6814
英文摘要	The Aoyougou mafic-ultramafic complex lies in the Paleozoic orogenic belt of the western part of the North Qilian Mountains near Aoyougou valley in Gansu Province, northwestern China. It consists of serpentinite, a cumulate sequence of gabbro and diorite. pillowed and massive lavas, diabase dikes, and chert, an assemblage tentatively interpreted as an ophiolite. SHRIMP dates on zircons from the diabase dikes indicate a crystallization age of 1777 +/- 28 Ma. The basalts show light rare-earth element enrichment and have relatively high TiO(2) and low Al(2)O(3) contents, characteristic of present-day E-MORB or ocean-island lavas. All of the lavas have relatively low MgO contents and Mg numbers [100Mg/(Mg+Fe)], indicating a somewhat evolved character. The diabase dikes have flat chondrite-normalized REE patterns and are significantly more primitive than the lavas. Based on the lava geochemistry, the nature of the serpentinite, and the regional geology, the Aoyougou complex is interpreted as a fragment of oceanic lithosphere that may have formed at an oceanic spreading axis. Later subduction of oceanic lithosphere in the Middle Proterozoic produced a trench-arc-basin system, which is preserved in the North Qilian Mountains. The tectonically dismembered Aoyougou complex is similar in many respects to Phanerozoic ophiolites and suggests that modern-style plate tectonic processes in China may have begun as early as the Middle Proterozoic.
学科主题	火成岩岩石学
WOS关键词	ROCKS ; ORIGIN
WOS研究方向	Geology
语种	英语
出版者	TAYLOR & FRANCIS INC
WOS记录号	WOS:000185729300006
内容类型	期刊论文
源URL	[http://119.78.100.197/handle/2HKVOGP0/37604]
专题	中国地质科学院地质研究所
作者单位	1.Chinese Acad Geol Sci, Inst Geol, Beijing 100037, Peoples R China. 2.Chinese Acad Geol Sci, Inst Mineral Deposits, Beijing 100037, Peoples R China. 3.Dalhousie Univ, Dept Earth Sci, Halifax, NS B3H 3J5, Canada. 4.Univ Hong Kong, Dept Earth Sci, Hong Kong, Hong Kong, Peoples R China. 5.Inst Geol, Gansu Bur Geol & Mineral Resources, Lanzhou 730000, Peoples R China. 6.中国地质科学院地质研究所
推荐引用方式 GB/T 7714	Zhang, ZC,Mao, JW,Robinson, PT,et al. The Aoyougou mafic-ultramafic complex in the North Qilian Mountains,;northwest China: A possible Middle Proterozoic ophiolite along the;southern margin of the North China craton[J]. INTERNATIONAL GEOLOGY REVIEW,2003,45(9):841-856.
APA	Zhang, ZC.,Mao, JW.,Robinson, PT.,Zhou, MF.,Zuo, GC.,...&Zhang, ZH.(2003).The Aoyougou mafic-ultramafic complex in the North Qilian Mountains,;northwest China: A possible Middle Proterozoic ophiolite along the;southern margin of the North China craton.INTERNATIONAL GEOLOGY REVIEW,45(9),841-856.
MLA	Zhang, ZC,et al."The Aoyougou mafic-ultramafic complex in the North Qilian Mountains,;northwest China: A possible Middle Proterozoic ophiolite along the;southern margin of the North China craton".INTERNATIONAL GEOLOGY REVIEW 45.9(2003):841-856.