气候变化领域集成服务门户(CCPortal): Early dextral shear motion during the breakup of East Gondwana documented in clastic dykes in the Tethys Himalaya

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DOI	10.1016/j.tecto.2023.230132
	Early dextral shear motion during the breakup of East Gondwana documented in clastic dykes in the Tethys Himalaya
	Wang, Jingyu; Li, Xianghui; White, Lloyd T.; Li, Yongxiang; Zhou, Juanjuan; Wei, Shoucai; Wei, Zhen; Zhou, Min; Fan, Xiaolong
发表日期	2024
ISSN	0040-1951
EISSN	1879-3266
起始页码	872
卷号	872
英文摘要	Much of the geological record of the northern Indian passive continental margin has been lost due to erosion or obscured due to tectonic burial associated with the India-Eurasia collision. Consequently, tectonic models of India's breakup from East Gondwana incorporate limited data from the northern margin of Greater India. We present evidence of the Late Jurassic clastic dykes crosscutting contemporaneous sedimentary sequences in the Tethys Himalaya. We propose that the original orientation of the clastic dykes provides kinematic information about Greater India's breakup from East Gondwana. The clastic dykes are meters to hundreds of meters long and centimeters to meters wide. They taper downwards and crosscut country rocks at high angles. The clastic dykes and their host strata are quartzose sandstones and share similar textures and detrital zircon age populations (dominantly 600-500 Ma and 1000-800 Ma zircon grains). These similarities indicate the clastic dykes and their host rocks share a common source as well as comparable transport and deposition dynamics. Notably, the clastic dykes lack distinct signs of ptygmatic folds, shale/mudrock clasts, surface orientated structures, or bifurcations on dyke margins. Decompaction and structural restoration of the sequences show that the sandstone dykes/ fractures and en echelon dyke arrays can be classified into three distinct orientation groups NW (349 degrees - 295(degrees)), SW (-210(degrees)) and NE (-40(degrees)). There is no apparent difference in the age or provenance of the clastic material within the different orientation groups. We propose that the clastic dykes signify passively infilled tensile fractures formed within a NW-SE dextral strike-slip megashear system during the Late Jurassic. This system likely developed in a transform zone within Greater India prior to the separation of the Indian Plate from East Gondwana.
英文关键词	Quartz sandstone; Shear system; Transform zone; Late Jurassic; Tethys Himalaya; Greater India
语种	英语
WOS研究方向	Geochemistry & Geophysics
WOS类目	Geochemistry & Geophysics
WOS记录号	WOS:001171223600001
来源期刊	TECTONOPHYSICS
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/304928
作者单位	Nanjing University; University of Wollongong; Xinjiang University
推荐引用方式 GB/T 7714	Wang, Jingyu,Li, Xianghui,White, Lloyd T.,et al. Early dextral shear motion during the breakup of East Gondwana documented in clastic dykes in the Tethys Himalaya[J],2024,872.
APA	Wang, Jingyu.,Li, Xianghui.,White, Lloyd T..,Li, Yongxiang.,Zhou, Juanjuan.,...&Fan, Xiaolong.(2024).Early dextral shear motion during the breakup of East Gondwana documented in clastic dykes in the Tethys Himalaya.TECTONOPHYSICS,872.
MLA	Wang, Jingyu,et al."Early dextral shear motion during the breakup of East Gondwana documented in clastic dykes in the Tethys Himalaya".TECTONOPHYSICS 872(2024).