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DOI	10.1007/s11434-012-5228-6
	Ductile deformation within Upper Himalaya Crystalline Sequence and geological implications, in Nyalam area, Southern Tibet
	Liu XiaoBing; Liu XiaoHan; Leloup, P. H.; Maheo, G.; Paquette, J. L.; Zhang XinGang; Zhou XueJun
通讯作者	Liu, XB (通讯作者)
发表日期	2012
ISSN	1001-6538
EISSN	1861-9541
起始页码	3469
结束页码	3481
卷号	57 期号:26
英文摘要	The South Tibet Detachment System (STDS) is a flat normal fault that separates the Upper Himalaya Crystalline Sequence (UHCS) below from the Tethyan Sedimentary Sequence (TSS) above. Timing of deformations related to the STDS is critical to understand the mechanism and evolution of the Himalaya collision zone. The Nyalam detachment (ND) (similar to 86A degrees E) locates in the middle portion of STDS (81A degrees aEuro89A degrees E). Dating of deformed leucocratic dykes that are most probably syntectonic at different depth beneath the ND, allow us to constrain the timing of deformation. (1) Dyke T11N37 located similar to 3500 m structurally below the ND emplaced at 27.4 +/- 0.2 Ma; (2) Dyke T11N32 located similar to 1400 m structurally below the ND emplaced at 22.0 +/- 0.3 Ma; (3) T11N25 located within the top to the north STD shear zone, similar to 150 m structurally below the ND, emplaced at 17.1 +/- 0.2 Ma. Combining ND footwall cooling history and T11N25 deformation temperature, we indicate a probable onset of top to the north deformation at similar to 16 Ma at this location. These results show an upward younging of the probable timing of onset of the deformation at different structural distance below the ND. We then propose a new model for deformation migration below the ND with deformation starting by pure shear deformation at depth prior to similar to 27.5 Ma that migrates upward at a rate of similar to 0.3 mm/a until similar to 18 Ma when deformation switches to top to the north shearing in the South Tibet Detachment shear zone (STDsz). As deformation on the ND stops at 14-13 Ma this would imply that significant top to the North motion would be limited to less than 5 Ma and would jeopardize the importance of lower channel flow.
关键词	U-TH-PB MANASLU LEUKOGRANITE DETACHMENT SYSTEM EVEREST REGION TECTONIC DENUDATION METAMORPHIC CORE RONGBUK VALLEY MONAZITE EXHUMATION GEOCHRONOLOGY
英文关键词	Upper Himalaya Crystalline Sequence (UHCS); South Tibet Detachment shear zone (STDsz); Nyalam detachment (ND); monazite-zircon U-Th/Pb dating; deformation migration
语种	英语
WOS研究方向	Science & Technology - Other Topics
WOS类目	Multidisciplinary Sciences
WOS记录号	WOS:000308239400013
来源期刊	CHINESE SCIENCE BULLETIN
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/258085
推荐引用方式 GB/T 7714	Liu XiaoBing,Liu XiaoHan,Leloup, P. H.,et al. Ductile deformation within Upper Himalaya Crystalline Sequence and geological implications, in Nyalam area, Southern Tibet[J]. 中国科学院青藏高原研究所,2012,57(26).
APA	Liu XiaoBing.,Liu XiaoHan.,Leloup, P. H..,Maheo, G..,Paquette, J. L..,...&Zhou XueJun.(2012).Ductile deformation within Upper Himalaya Crystalline Sequence and geological implications, in Nyalam area, Southern Tibet.CHINESE SCIENCE BULLETIN,57(26).
MLA	Liu XiaoBing,et al."Ductile deformation within Upper Himalaya Crystalline Sequence and geological implications, in Nyalam area, Southern Tibet".CHINESE SCIENCE BULLETIN 57.26(2012).