气候变化领域集成服务门户(CCPortal): Provenance and erosional impact of Quaternary megafloods through the Yarlung-Tsangpo Gorge from zircon U-Pb geochronology of flood deposits, eastern Himalaya

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DOI	10.1016/j.epsl.2020.116113
	Provenance and erosional impact of Quaternary megafloods through the Yarlung-Tsangpo Gorge from zircon U-Pb geochronology of flood deposits, eastern Himalaya
	Turzewski M.D.; Huntington K.W.; Licht A.; Lang K.A.
发表日期	2020
ISSN	0012821X
卷号	535
英文摘要	Holocene and Upper Pleistocene sediments in the eastern Himalayan syntaxis represent an extraordinary record of glacial outburst megafloods in one of the most tectonically active landscapes on Earth. Glacial damming and outburst floods in the syntaxis may have focused erosion in the steep Tsangpo Gorge and inhibited river incision into the margin of the Tibetan Plateau. However, few flood slackwater deposits have been studied, and it is unknown which of the hundreds of known glacial impoundments in Tibet may have sourced the floods. Here we report n=1438 new detrital zircon U-Pb data from individual ancient megaflood and historical outburst flood slackwater deposits to examine the provenance and erosive potential of these events. Detrital zircon U-Pb geochronology of megaflood deposits show that megaflood provenance is more consistent with impoundment of the Yarlung River drainage at or west of the Namche Barwa massif, than impoundment of eastern drainages along the Yigong and Parlung Rivers. Compared to active bedload in the Siang River, and historical floods within the same drainage area, megaflood samples overall contain a disproportionately large amount of zircons eroded from the Tsangpo Gorge. We interpret this preferential derivation to reflect preferential erosion during large discharge events—supporting the hypothesis that Quaternary megafloods are a primary contributor to rapid exhumation of the eastern Himalayan syntaxis. © 2020 Elsevier B.V.
关键词	erosion geochronology Himalaya megaflood zircon
英文关键词	Binary alloys; Deposits; Erosion; Floods; Geochronology; Glacial geology; Lead alloys; Rivers; Silicate minerals; Uranium alloys; Zircon; Detrital zircon; Himalayas; Historical floods; megaflood; Outburst floods; Pleistocene sediments; Tibetan Plateau; Zircon U-Pb geochronologies; Zircon deposits; exhumation; flood; flood deposit; geochronology; Holocene; impoundment; outburst; provenance; uranium-lead dating; zircon; Brahmaputra Basin; Himalayas
语种	英语
来源期刊	Earth and Planetary Science Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/202939
作者单位	Department of Earth and Space Sciences, Quaternary Research Center, University of Washington, Seattle, WA, United States; School of Earth and Environmental Sciences, Queens College, Queens, NY, United States; Graduate Center, City University of New York, New York, NY, United States
推荐引用方式 GB/T 7714	Turzewski M.D.,Huntington K.W.,Licht A.,et al. Provenance and erosional impact of Quaternary megafloods through the Yarlung-Tsangpo Gorge from zircon U-Pb geochronology of flood deposits, eastern Himalaya[J],2020,535.
APA	Turzewski M.D.,Huntington K.W.,Licht A.,&Lang K.A..(2020).Provenance and erosional impact of Quaternary megafloods through the Yarlung-Tsangpo Gorge from zircon U-Pb geochronology of flood deposits, eastern Himalaya.Earth and Planetary Science Letters,535.
MLA	Turzewski M.D.,et al."Provenance and erosional impact of Quaternary megafloods through the Yarlung-Tsangpo Gorge from zircon U-Pb geochronology of flood deposits, eastern Himalaya".Earth and Planetary Science Letters 535(2020).