The subduction-accretion history of the Bangong-Nujiang Ocean: Constraints from provenance and geochronology of the Mesozoic strata near Gaize, central Tibet

doi:10.1016/j.tecto.2017.02.023

	The subduction-accretion history of the Bangong-Nujiang Ocean: Constraints from provenance and geochronology of the Mesozoic strata near Gaize, central Tibet
	Li, S (Li, Shun)2,3; Ding, L (Ding, Lin)1,3; Guilmette, C (Guilmette, Carl)2; Fu, JJ (Fu, Jiajun)4; Xu, Q (Xu, Qiang)1,3; Yue, YH (Yue, Yahui)3; Henrique-Pinto, R (Henrique-Pinto, Renato)2; Li, S
刊名	TECTONOPHYSICS
	2017
卷号	702 期号:0 页码:42-60
关键词	ZIRCON U-PB PALEO-TETHYS OCEAN TRIASSIC ARC MAGMATISM SOUTHERN TIBET TECTONIC EVOLUTION NEO-TETHYS LHASA TERRANE OROGENIC BELT WESTERN CHINA LU-HF
DOI	10.1016/j.tecto.2017.02.023
文献子类	Article
英文摘要	The Mesozoic strata, within the Bangong-Nujiang suture zone in central Tibet, recorded critical information about the subduction-accretion processes of the Bangong-Nujiang Ocean prior to the Lhasa-Qiangtang collision. This paper reports detailed field observations, petrographic descriptions, sandstone detrital zircon U-Pb ages and Hf isotopic analyses from an accretionary complex (preserved as Mugagangri Group) and the unconformably overlying Shamuluo Formation near Gaize. The youngest detrital zircon ages, together with other age constraints from literature, suggest that the Mugagangri Group was deposited during late Triassic-early Jurassic, while the Shamuluo Formation was deposited during late Jurassic-early Cretaceous. Based on the differences in lithology, age and provenance, the Mugagangri Group is subdivided into the upper, middle and lower subunits. These units are younging structurally downward/southward, consistent with models of progressive off-scrapping and accretion in a southward-facing subduction complex. The upper subunit, comprising mainly quartz-sandstone and siliceous mud/shale, was deposited in abyssal plain environment close to the Qiangtang passive margin during late Triassic, with sediments derived from the southern Qiangtang block. The middle and lower subunits comprise mainly lithic-quartz-sandstone and mud/shale, containing abundant ultramafic/ophiolitic fragments. The middle subunit, of late Triassic-early Jurassic age, records a transition in tectono-depositional setting from abyssal plain to trench-wedge basin, with sudden influx of sediments sourced from the central Qjangtang metamorphic belt and northern Qjangtang magmatic belt. The appearance of ultramafic/ophiolitic fragments in the middle subunit reflects the subduction initiation. The lower subunit was deposited in a trench-wedge basin during early Jurassic, with influx of Jurassic-aged zircons originating from the newly active southern Qiangtang magmatic arc. The lower subunit records the onset of arc magmatism related to the northward subduction of the Bangong-Nujiang Ocean. The Shamuluo Formation, comprising mainly lithic-feldspar-sandstone with limestone interlayers, was deposited in a post-collisional residual-sea or pre-collisional trench-slope basin, with sediments derived entirely from the Qiangtang block. (C) 2017 Elsevier B.V. All rights reserved.
学科主题	地质学
WOS研究方向	Geochemistry & Geophysics
语种	英语
WOS记录号	WOS:000399511100005
内容类型	期刊论文
源URL	[http://ir.itpcas.ac.cn/handle/131C11/8262]
专题	青藏高原研究所_图书馆
通讯作者	Li, S
作者单位	1.Chinese Acad Sci, Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. 2.Univ Laval, Dept Geol & Genie Geol, 1065 Ave Med, Quebec City, PQ G1V 0A6, Canada. 3.Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Continental Collis & Plateau Uplift, Beijing 100101, Peoples R China. 4.Fujian Inst Geol Survey, Fuzhou 350013, Peoples R China.
推荐引用方式 GB/T 7714	Li, S ,Ding, L ,Guilmette, C ,et al. The subduction-accretion history of the Bangong-Nujiang Ocean: Constraints from provenance and geochronology of the Mesozoic strata near Gaize, central Tibet[J]. TECTONOPHYSICS,2017,702(0):42-60.
APA	Li, S .,Ding, L .,Guilmette, C .,Fu, JJ .,Xu, Q .,...&Li, S.(2017).The subduction-accretion history of the Bangong-Nujiang Ocean: Constraints from provenance and geochronology of the Mesozoic strata near Gaize, central Tibet.TECTONOPHYSICS,702(0),42-60.
MLA	Li, S ,et al."The subduction-accretion history of the Bangong-Nujiang Ocean: Constraints from provenance and geochronology of the Mesozoic strata near Gaize, central Tibet".TECTONOPHYSICS 702.0(2017):42-60.