Early Paleozoic tectonic evolution of the southern Beishan orogenic collage: Insights from the granitoids

	Early Paleozoic tectonic evolution of the southern Beishan orogenic collage: Insights from the granitoids
	He ZhenYu 4; Zong KeQing 1; Jiang HongYing 2; Xiang Hua ; Zhang ZeMing
刊名	ACTA PETROLOGICA SINICA
	2014
卷号	30 期号:8 页码:2324-2338
关键词	Early Paleozoic granites Shibanshan block Dunhuang block Collisional orogeny Beishan orogenic collage
ISSN号	1000-0569
英文摘要	The Beishan orogenic collage represents a major part of the southern Central Asian Orogenic Belt (CAOB), which is a tectonically significant region between the Tianshan orogen and the Solonker Suture Zone. It would provide important clues for examining the accretionary orogenic processes of the CAOB and the final closure event of the Paleo-Asian Ocean. In this work, we present LA-ICP-MS U-Pb zircon dating, LA-MC-ICP-MS zircon Hf isotopic and geochemical results for the Early Paleozoic granites from the Qiaowan and Jinta areas in the southern Beishan and to revisit their tectonic setting and the Early Paleozoic tectonic evolution of the southern Beishan. The Qiaowan granite in the Baidunzi-Qiaowan shear zone is variously deformed, consisting of quartz, Kfeldspar,, plagioclase (An = 21 similar to 27), biotite and amphibole. Biotite grains are compositionally similar and have relatively low TiO2 contents, and amphibole is blue-green with compositions of ferro-pargasite. The Jinta syenogranite is not deformed, medium- to fine-grained, consists of quartz, K-feldspar, plagioclase and biotite. Plagioclase exhibits oscillatory zoning. The Qiaowan mylonitic granite and Jinta syenogranite have a similar age of similar to 430Ma, with two-stage zircon Hf model ages of 2.14 similar to 2.37Ga and 1.32 similar to 1.72Ga, respectively. The inherited zircon cores in them exhibit Hf isotope compositions similar to those of the Neoproterozoic granitic gneisses in the southern Beishan. Both the Qiaowan mylonitic granite and Jinta syenogranite show high SiO, (between 73.18% and 75.00%) and weakly peraluminous, they are enriched in Rb, U and K, and depleted in Ba, Nb, Ta, Sr, P and Ti, which can be compared with other Early Paleozoic syenogranites from the southern Beishan. They are suggested to derive from a Paleoproterozoic-Mesoproterozoic crustal source in the southern Beishan, while the Jinta syenogranite also has a depleted mantle or new crust contribution, indicating that the basement rocks of the Shibanshan block in the southern Beishan do not resemble those of the Dunhuang block. We suggest, in accordance with the studies of the Early Paleozoic HP granulite in the Dunhuang block, that the Early Paleozoic magmatisms in the southern Beishan is the result of the collision and continued convergence between the Dunhuang and Shibanshan blocks, and that the Beishan orogenic collage underwent Early Paleozoic accretionary and collisional orogenic processes involved microcontinents within the orogen and the surrounding cratons.
学科主题	构造地质学
WOS关键词	ZIRCON U-PB ; NORTHEASTERN TARIM CRATON ; NW CHINA EVIDENCE ; DUNHUANG BLOCK ; CENTRAL-ASIA ; GEOCHEMICAL CHARACTERISTICS ; GEOCHRONOLOGICAL EVIDENCE ; ACCRETIONARY OROGENS ; NORTHWESTERN CHINA ; CONTINENTAL GROWTH
WOS研究方向	Geology
语种	中文
出版者	SCIENCE PRESS
WOS记录号	WOS:000340023300015
内容类型	期刊论文
源URL	[http://119.78.100.197/handle/2HKVOGP0/40528]
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, State Key Lab Continental Tecton & Dynam, Beijing 100037, Peoples R China 2.China Univ Geosci, State Key Lab Geol Proc & Mineral Resources, Wuhan 430074, Peoples R China 3.China Univ Geosci, Sch Earth Sci & Resources, Beijing 100083, Peoples R China 4.中国地质科学院地质研究所
推荐引用方式 GB/T 7714	He ZhenYu,Zong KeQing,Jiang HongYing,et al. Early Paleozoic tectonic evolution of the southern Beishan orogenic collage: Insights from the granitoids[J]. ACTA PETROLOGICA SINICA,2014,30(8):2324-2338.
APA	He ZhenYu,Zong KeQing,Jiang HongYing,Xiang Hua,&Zhang ZeMing.(2014).Early Paleozoic tectonic evolution of the southern Beishan orogenic collage: Insights from the granitoids.ACTA PETROLOGICA SINICA,30(8),2324-2338.
MLA	He ZhenYu,et al."Early Paleozoic tectonic evolution of the southern Beishan orogenic collage: Insights from the granitoids".ACTA PETROLOGICA SINICA 30.8(2014):2324-2338.