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DOI	10.1016/j.quageo.2022.101303
	Luminescence dating of a megaflood event on a terrace of the Jinsha River, China
	Hu, Gang; Min, Rui; Zhou, Yiheng; Yang, Jishuai; Wang, Yanren; Wang, Chunxin; Wang, Huiying; Wang, Ping; Wang, Lei; Fan, Anchuan
通讯作者	Hu, G (通讯作者)
发表日期	2022
ISSN	1871-1014
EISSN	1878-0350
卷号	70
英文摘要	The numerical dating of megaflood sediments is a worldwide challenge, a fact that has impeded a full understanding of Late Quaternary dam-outburst flood processes that occurred along the river courses of the Tibetan Plateau. Optically stimulated luminescence (OSL) dating has been widely used on such sediments. Due to their short transportation distances prior to deposition, the OSL signals of megaflood sediments are often partially bleached, resulting in age overestimations. Here, we report on a comparison of OSL ages obtained using both quartz (4-11 mu m FG; 90-125, 180-250 mu m CG) and K-feldspar (180-250 mu m CG) extracted from sediments taken from the Binghong-Bingnong Neolithic-Bronze Age site on the second Jinshan River terrace (T2), in Yunnan Province, southwestern China. Contrary to previous experience suggesting that CG fractions are usually better bleached than FG fractions prior to deposition, our results showed that the OSL ages for the FG quartz fraction were generally younger than those for the CG fraction. This would suggest that the two fractions may have come from different sources, and may have been subject to different geomorphological processes prior to deposition. FG quartz fractions may be suitable to define the maximum age of sediments located in alpine gorge regions. CG quartz fractions can be used by applying the minimum age model (MAM) to select relatively well-bleached grains yielded ages close to the 'true' burial ages of the sediments. The results showed that the post-IR IRSL225 ages of single grain K-feldspar were overestimated by > 3 ka, suggesting K-feldspar may not be suitable dating material for megaflood sediments <30 ka. The OSL dates suggest that the T2 terrace was formed -8.4 ka, that aeolian sediments were deposited during -2.6-1.5 ka, and that the megaflood event occurred after -1.5 ka.
关键词	OPTICALLY STIMULATED LUMINESCENCE GRAIN-SIZE QUATERNARY SEDIMENTS HOLOCENE SEDIMENTS TSANGPO GORGE DAMMED LAKE INDUS RIVER QUARTZ SINGLE DEPOSITS
英文关键词	Megaflood sediment; OSL dating; Different grain size fractions; Partial bleaching; Jinsha river
语种	英语
WOS研究方向	Physical Geography ; Geology
WOS类目	Geography, Physical ; Geosciences, Multidisciplinary
WOS记录号	WOS:000795782000004
来源期刊	QUATERNARY GEOCHRONOLOGY
来源机构	中国科学院青藏高原研究所
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/260679
推荐引用方式 GB/T 7714	Hu, Gang,Min, Rui,Zhou, Yiheng,et al. Luminescence dating of a megaflood event on a terrace of the Jinsha River, China[J]. 中国科学院青藏高原研究所,2022,70.
APA	Hu, Gang.,Min, Rui.,Zhou, Yiheng.,Yang, Jishuai.,Wang, Yanren.,...&Fan, Anchuan.(2022).Luminescence dating of a megaflood event on a terrace of the Jinsha River, China.QUATERNARY GEOCHRONOLOGY,70.
MLA	Hu, Gang,et al."Luminescence dating of a megaflood event on a terrace of the Jinsha River, China".QUATERNARY GEOCHRONOLOGY 70(2022).