气候变化领域集成服务门户(CCPortal): Impact of extreme debris flow-induced paleodamming events on the sedimentological evolution of the middle Yarlung Tsangpo River reaches since the late Pleistocene, Tibet

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DOI	10.3389/feart.2022.1017858
	Impact of extreme debris flow-induced paleodamming events on the sedimentological evolution of the middle Yarlung Tsangpo River reaches since the late Pleistocene, Tibet
	Wang, Huiying; Wang, Ping; Hu, Gang; Yuan, Renmao; Ge, Yukui; Xu, Bo; Shi, Lingfan
发表日期	2023
EISSN	2296-6463
卷号	10
英文摘要	As extreme surface processes, long-term river damming and outburst events can impact sediment supply and transportation in valleys and therefore significantly change the landscape. Lacustrine sediments were identified in the wide Xigaze Valley, in the middle reaches of the Yarlung Tsangpo River in Tibet, an area which has been considered to have been a paleodammed lake. However, the evolutionary process and damming mechanisms associated with this paleolake, and any subsequent impact on sedimentation within the valley, remain unclear. Here, we present a detailed geomorphological and sedimentary analysis of the proposed paleolake area, based on a study of a prominent valley fill found along a section of the Yarlung Tsangpo River and its tributary that flows into it from the south, the Menchu River. This section stretches from Xigaze to Dazhuka. Sedimentary facies analysis of two stratigraphic sections in Renbu Town showed that at least two paleolakes caused by debris flow related to glaciers developed in the Xigaze Valley and that the paleodam was located near the outlet of the Dazhuka Gorge. Chronological constraints suggest that the first damming event occurred between & SIM;48.6 and 33.7 ka in Marine Isotope Stage (MIS) 3 and had a minimum lake surface elevation of similar to 3,820 m. The second damming occurred between similar to 24.3 and 12.7 ka during the Last Glacial Maximum (LGM), producing a lake surface elevation of at least similar to 3,760 m. During the development of the paleolakes in the Xigaze Valley, several small-scale damming and outburst events happened in the upper and middle reaches of the Menchu River, resulting in fluviolacustrine and outburst flood sediments accumulating in the main stream of the Yarlung Tsangpo River and forming thick-fill terraces. We presumed that the paleolakes in the middle reaches of the Yarlung Tsangpo River gradually drained as a result of continuous overflow undercutting instead of outburst flood events, thereby allowing fluvial aggradation of the upper reaches of the paleodam.
关键词	Yarlung Tsangpo debris flow dammed paleolake sedimentary facies drainage evolution
英文关键词	DAMMED LAKE; GLACIOLACUSTRINE DEPOSITS; SUBAQUEOUS FAN; GLACIAL LAKES; PALAEO-LAKE; VALLEY; GORGE; ICE; SYNTAXIS; PLATEAU
WOS研究方向	Geosciences, Multidisciplinary
WOS记录号	WOS:000924901500001
来源期刊	FRONTIERS IN EARTH SCIENCE
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/283357
作者单位	China Earthquake Administration
推荐引用方式 GB/T 7714	Wang, Huiying,Wang, Ping,Hu, Gang,et al. Impact of extreme debris flow-induced paleodamming events on the sedimentological evolution of the middle Yarlung Tsangpo River reaches since the late Pleistocene, Tibet[J],2023,10.
APA	Wang, Huiying.,Wang, Ping.,Hu, Gang.,Yuan, Renmao.,Ge, Yukui.,...&Shi, Lingfan.(2023).Impact of extreme debris flow-induced paleodamming events on the sedimentological evolution of the middle Yarlung Tsangpo River reaches since the late Pleistocene, Tibet.FRONTIERS IN EARTH SCIENCE,10.
MLA	Wang, Huiying,et al."Impact of extreme debris flow-induced paleodamming events on the sedimentological evolution of the middle Yarlung Tsangpo River reaches since the late Pleistocene, Tibet".FRONTIERS IN EARTH SCIENCE 10(2023).