气候变化领域集成服务门户(CCPortal): Oligocene Orogen-Parallel Extension in Southern Tibet During Indian Continental Subduction

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DOI	10.1029/2023GL105193
	Oligocene Orogen-Parallel Extension in Southern Tibet During Indian Continental Subduction
	Xue, Weiwei; Hu, Xiumian; Ma, Anlin; Garzanti, Eduardo; Liang, Wendong; Hao, Lulu; Wang, Qiang
发表日期	2023
ISSN	0094-8276
EISSN	1944-8007
卷号	50 期号:20
英文摘要	The controversial history of Indian subduction beneath Asia is crucial to understand the Himalayan orogeny and more in general the geodynamic process of continental subduction. New key information is here presented from the Oligocene-Pliocene Shiquanhe Basin located in the southwestern Tibetan Plateau. The alluvial-fan, lacustrine, and braided-river sediments of the Oligocene Rigongla Formation were non-conformably deposited onto the Upper Cretaceous Gangdese granitoid rocks and fed from erosion of the batholith itself and of associated Paleogene Linzizong volcanic rocks. Stratigraphic evidence testifies to the development of an orogen-parallel intracontinental rift along the retro-side of the Gangdese arc in the Oligocene, at the same time as the Kailas basin formed along the pro-side of the Gangdese arc. The subsidence of these twin basins may have been caused by steepening of the subducting Indian continental slab or by the passage of a wave of dynamic topography during continuing subduction. The convergence and collision of India and Asia leading to the formation of the Himalayan Mountains and Tibetan Plateau (the roof of the world) is one of the most significant geological events of the Cenozoic Era. Geophysical data show that rocks of the Indian continent lie beneath southern Tibet, but the early subduction history of India related to the initial topographic grow of the Himalaya remains unclear. We studied the Shiquanhe Basin in southwestern Tibet to investigate the continent's subduction history using stratigraphic, sedimentological, and provenance analyses. Our results indicate that an orogen-parallel rift developed in southern Tibet during the Oligocene Epoch. Challenging earlier beliefs, we propose two alternative models to explain such event of tectonic extension: steepening of subduction angle or passage of a topographic wave across the subducting plate. The latter hypothesis would also explain the widespread uplift and lack of Oligocene sedimentary deposits recorded all across the front of the Himalayan range. Oligocene Rigongla Fm. testifies to orogen-parallel extension along retro-side of Gangdese arcShiquanhe Basin passed from extension to compression in Oligocene to Miocene timesOligocene extension was caused by change of Indian subduction angle or wave of dynamic topography
关键词	Himalayan-Tibetan orogen orogenic extension Lhasa terrane Shiquanhe basin Rigongla Formation
英文关键词	BENEATH SOUTHERN; MAGMATISM; COLLISION; HIMALAYA; GEOCHEMISTRY; DIACHRONEITY; PALEOCENE; EVOLUTION; INSIGHTS; RECORD
WOS研究方向	Geosciences, Multidisciplinary
WOS记录号	WOS:001087653800001
来源期刊	GEOPHYSICAL RESEARCH LETTERS
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/282941
作者单位	Chinese Academy of Sciences; Guangzhou Institute of Geochemistry, CAS; Nanjing University; University of Milano-Bicocca; Chengdu University of Technology
推荐引用方式 GB/T 7714	Xue, Weiwei,Hu, Xiumian,Ma, Anlin,et al. Oligocene Orogen-Parallel Extension in Southern Tibet During Indian Continental Subduction[J],2023,50(20).
APA	Xue, Weiwei.,Hu, Xiumian.,Ma, Anlin.,Garzanti, Eduardo.,Liang, Wendong.,...&Wang, Qiang.(2023).Oligocene Orogen-Parallel Extension in Southern Tibet During Indian Continental Subduction.GEOPHYSICAL RESEARCH LETTERS,50(20).
MLA	Xue, Weiwei,et al."Oligocene Orogen-Parallel Extension in Southern Tibet During Indian Continental Subduction".GEOPHYSICAL RESEARCH LETTERS 50.20(2023).