气候变化领域集成服务门户(CCPortal): Cenozoic anatexis and exhumation of Tethyan Sequence rocks in the Xiao Curia Range, Southwest Tibet

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DOI	10.1016/j.tecto.2011.01.008
	Cenozoic anatexis and exhumation of Tethyan Sequence rocks in the Xiao Curia Range, Southwest Tibet
	Pullen, Alex; Kapp, Paul; DeCelles, Peter G.; Gehrels, George E.; Ding, Lin
通讯作者	Pullen, A (通讯作者)
发表日期	2011
ISSN	0040-1951
EISSN	1879-3266
起始页码	28
结束页码	40
卷号	501 期号:1-4
英文摘要	In order to advance our understanding of the suturing process between continental landmasses, a geologic and geochronologic investigation was undertaken just south of the India-Asia suture in southwestern Tibet. The focus of this study, the Xiao Gurla Range, is located near the southeastern terminus of the active, right-lateral strike-slip Karakoram fault in southwestern Tibet. The range exposes metasandstone, phyllite, schist (locally of sillimanite facies), calc-gneiss and marble, paragneiss (+/- pyroxene), quartzite, metagranite, and variably deformed leucogranite. These metamorphic rocks are exposed in the footwall of a domal, top-to-the-west low-angle normal (detachment) fault, structurally beneath Neogene-Quaternary basin fill and serpentinized ultramafic rocks of the Kiogar-Jungbwa ophiolite. The detachment is interpreted to be the northeastern continuation of the Gurla Mandhata detachment fault system that bounds metamorphic rocks of the Curia Mandhata Range similar to 60 km to the southwest. U-Pb geochronology on five detrital zircon samples of schist, phyllite, and quartzite yielded maximum depositional ages that range from 644-363 Ma and age probability distributions that are more similar to Tethyan sequence rocks than Lesser Himalayan sequence rocks. A felsic gneiss yielded a metamorphic zircon age of 35.3 +/- 0.8 Ma with a significant population of early Paleozoic xenocrystic core ages. The gneiss is interpreted to be the metamorphosed equivalent of the Cambro-Ordovician gneiss that is exposed near the top of the Greater Himalayan sequence. Leucogranitic bodies intruding metasedimentary footwall rocks yielded two distinct U-Pb zircon ages of similar to 23 Ma and similar to 15 Ma. Locally, rocks exposed in the hanging wall of this fault and of the southward-dipping, northward-verging Great Counter thrust to the north consist of serpentinite-bearing melange and conglomerate of inferred Paleogene age dominated by carbonate clasts. The melange is intruded by a 44 Ma granite and the stratigraphically highest conglomerate unit yielded detrital zircon U-Pb ages similar to Tethyan sequence rocks. We attribute the middle Eocene magmatism south of the suture to break-off of the Neo-Tethyan oceanic slab. In addition, our observations are consistent with the late Eocene shortening and crustal thickening within the Tethyan Himalayan sequence, early-middle Miocene leucogranite emplacement being related to underthrusting and melting of the Greater and possibly Lesser Himalayan sequences, and late Miocene arc-parallel extension in the hinterland of the southward propagating Himalayan thrust belt. (C) 2011 Elsevier B.V. All rights reserved.
关键词	INDIA-ASIA COLLISION FOLD-THRUST BELT PB GEOCHRONOLOGICAL EVIDENCE HIMALAYAN METAMORPHIC CORE EARLY PALEOZOIC TECTONISM KARAKORAM FAULT ZONE EAST-WEST EXTENSION SOUTHERN TIBET STRUCTURAL EVOLUTION CENTRAL NEPAL
英文关键词	Tethyan Himalayan sequence; Gurla Mandhata; Leucogranite; India-Asia suture; U-Pb zircon
语种	英语
WOS研究方向	Geochemistry & Geophysics
WOS类目	Geochemistry & Geophysics
WOS记录号	WOS:000289452000003
来源期刊	TECTONOPHYSICS
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/257907
推荐引用方式 GB/T 7714	Pullen, Alex,Kapp, Paul,DeCelles, Peter G.,et al. Cenozoic anatexis and exhumation of Tethyan Sequence rocks in the Xiao Curia Range, Southwest Tibet[J]. 中国科学院青藏高原研究所,2011,501(1-4).
APA	Pullen, Alex,Kapp, Paul,DeCelles, Peter G.,Gehrels, George E.,&Ding, Lin.(2011).Cenozoic anatexis and exhumation of Tethyan Sequence rocks in the Xiao Curia Range, Southwest Tibet.TECTONOPHYSICS,501(1-4).
MLA	Pullen, Alex,et al."Cenozoic anatexis and exhumation of Tethyan Sequence rocks in the Xiao Curia Range, Southwest Tibet".TECTONOPHYSICS 501.1-4(2011).