气候变化领域集成服务门户(CCPortal): Polystage deformation of the Gaoligong metamorphic zone: Structures, Ar-40/Ar-39 mica ages, and tectonic implications

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DOI	10.1016/j.jsg.2012.02.007
	Polystage deformation of the Gaoligong metamorphic zone: Structures, Ar-40/Ar-39 mica ages, and tectonic implications
	Zhang, Bo; Zhang, Jinjiang; Zhong, Dalai; Yang, Liekun; Yue, Yahui; Yan, Shuyu
通讯作者	Zhang, B (通讯作者)
发表日期	2012
ISSN	0191-8141
起始页码	1
结束页码	18
卷号	37
英文摘要	The Gaoligong metamorphic zone is located southeast of the Eastern Himalayan Syntaxis in western Yunnan, China. The zone is characterized by four stages of deformation (D1-D4). D1 structures record early compressive deformation during the Indosinian orogeny, which formed tight to isoclinal F1 folds of bedding with a penetrative S1 foliation developed parallel to fold axial planes. Mid-crustal horizontal shearing during D2 resulted in overprinting of D1 structures. D1 and 02 structures are associated with granulite facies metamorphism. D3 doming resulted in late crustal thickening and the development of a regional NW-SE trending F3 antiform. Synchronous with or slightly subsequent to 03 deformation, the zone experienced D4 ductile strike-slip shearing, resulting in its exhumation to shallow crustal levels and retrograde metamorphism. Granitic D4 mylonites predominantly yield Ar-40/Ar-39 mica ages of 15-16 Ma, indicating that D4 dextral strike-slip shearing occurred in the Miocene. Weakly deformed leucogranite and protomylonite yield Ar-40/Ar-39 ages of 10-11 Ma, suggesting that ductile strike-slip shearing continued to the Late Miocene. The new Ar-40/Ar-39 data indicate that escape-related deformation along the Gaoligong strike-slip shear zone occurred in the Miocene. In association with recent geophysical studies, and on the basis of the structural, crystal preferred orientation (CPO), and geochronological data presented in this paper, we suggest that the Gaoligong metamorphic zone formed in response to intracontinental transpression in the southeast of Tibet, characterized as intense deformation and metamorphism at middle-upper crustal levels. (C) 2012 Elsevier Ltd. All rights reserved.
关键词	RIVER SHEAR ZONE DYNAMIC RECRYSTALLIZATION PREFERRED ORIENTATIONS WESTERN YUNNAN AILAO SHAN FABRIC DEVELOPMENT SOUTHEAST-ASIA INDO-CHINA SE MARGIN EVOLUTION
英文关键词	Structure; CPOs; Polystage deformation; Ar-40/Ar-39; Gaoligong metamorphic zone
语种	英语
WOS研究方向	Geology
WOS类目	Geosciences, Multidisciplinary
WOS记录号	WOS:000302758600001
来源期刊	JOURNAL OF STRUCTURAL GEOLOGY
来源机构	中国科学院青藏高原研究所
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/258027
推荐引用方式 GB/T 7714	Zhang, Bo,Zhang, Jinjiang,Zhong, Dalai,et al. Polystage deformation of the Gaoligong metamorphic zone: Structures, Ar-40/Ar-39 mica ages, and tectonic implications[J]. 中国科学院青藏高原研究所,2012,37.
APA	Zhang, Bo,Zhang, Jinjiang,Zhong, Dalai,Yang, Liekun,Yue, Yahui,&Yan, Shuyu.(2012).Polystage deformation of the Gaoligong metamorphic zone: Structures, Ar-40/Ar-39 mica ages, and tectonic implications.JOURNAL OF STRUCTURAL GEOLOGY,37.
MLA	Zhang, Bo,et al."Polystage deformation of the Gaoligong metamorphic zone: Structures, Ar-40/Ar-39 mica ages, and tectonic implications".JOURNAL OF STRUCTURAL GEOLOGY 37(2012).