Climate-induced changes in sediment supply revealed by surface exposure dating of Sijiquan River terraces, northeastern Tibet

doi:10.1016/j.geomorph.2015.01.017

CORC > 地质与地球物理研究所 > 中国科学院地质与地球物理研究所 > 岩石圈演化国家重点实验室

	Climate-induced changes in sediment supply revealed by surface exposure dating of Sijiquan River terraces, northeastern Tibet
	Shirahama, Yoshiki 1; Miyairi, Yosuke 2; He, Honglin 3; Fu, Bihong 4; Echigo, Tomoo 5; Kano, Ken'ichi 6; Yokoyama, Yusuke 2; Ikeda, Yasutaka 1
刊名	GEOMORPHOLOGY
	2015-04-15
卷号	235 页码:15-26
关键词	Fluvio-glacial Landforms Surface Exposure Dating Inherited Cosmogenic Radionuclides Grain-by-grain Measurements Climatic Geomorphology Tibetan Plateau
DOI	10.1016/j.geomorph.2015.01.017
文献子类	Article
英文摘要	In this paper, we report cosmogenic isotope evidence for dramatic changes in sediment supply during glacial interglacial climatic cycles in the Late Quaternary. Previous work on fluvio-glacial processes in cold environments has qualitatively revealed that significant increases in debris production occurred in glacial periods, due typically to accelerated glacial and periglacial processes on high-relief slopes, resulting in river aggradation (accumulation) in the drainage. In interglacial periods, rivers behave in the opposite way, forming incised valleys. However, little has been studied on climatically controlled production-and-reworking processes with radiometric evidence. The evidence presented here is from the northeastern margin of the Tibetan Plateau, where lateral growth of the plateau is now ongoing. Reconstructions of fluvial response to Quaternary glacial fluctuations are crucial also to better understand the active tectonic process in the region using geomorphological information. The Sijiquan River drainage basin on the north of the East Kunlun Mountains was investigated. Detailed geomorphological mapping of fluvio-glacial landforms indicates two phases of aggradation, each of which was followed by valley incision. Be-10 and Al-26 concentrations in fluvial terrace deposits suggest that these two aggradational phases correspond most likely to the penultimate and last glacial periods, assuming a low rate of surface erosion on the terraces and zero inherited concentration. On the other hand, present-day river gravel has higher concentrations in amalgamated samples of Be-10 and Al-26 than the terrace deposits. Surface-exposure and burial analyses based on grain-by-grain measurements of both Be-10 and Al-26 indicate that the present-day river gravel consists mostly of reworked grains from terrace deposits and underlying fluviolacustrine rocks in the drainage basin. It is concluded that significant changes in clastic sediment supply occur in cold environments in response to glacial interglacial cycles; clastic sediments are transported from mountain slopes much more directly in glacial periods than in interglacial periods. This violates the common assumption for surface exposure dating that the inherited cosmogenic isotope concentration is constant through time. (C) 2015 Elsevier B.V. All rights reserved.
WOS关键词	ALTYN-TAGH FAULT ; CENOZOIC TECTONIC EVOLUTION ; QAIDAM BASIN ; COSMOGENIC NUCLIDES ; NORTHERN TIBET ; AMS STANDARDS ; SLIP ; PLATEAU ; GROWTH ; BE-10
WOS研究方向	Physical Geography ; Geology
语种	英语
WOS记录号	WOS:000351800800002
资助机构	Japan Society for the Promotion of Science(22300314) ; Japan Society for the Promotion of Science(22300314) ; Japan Society for the Promotion of Science(22300314) ; Japan Society for the Promotion of Science(22300314)
内容类型	期刊论文
源URL	[http://ir.iggcas.ac.cn/handle/132A11/62561]
专题	地质与地球物理研究所_岩石圈演化国家重点实验室
作者单位	1.Univ Tokyo, Earth & Planetary Sci, Tokyo, Japan 2.Univ Tokyo, Atmosphere & Ocean Res Inst, Chiba, Japan 3.China Earthquake Adm, Inst Geol, Beijing, Peoples R China 4.Chinese Acad Sci, Inst Geol & Geophys, Beijing, Peoples R China 5.Geores Inst, Osaka, Japan 6.Shizuoka Univ, Ctr Integrated Res & Educ Nat Hazards, Shizuoka, Japan
推荐引用方式 GB/T 7714	Shirahama, Yoshiki,Miyairi, Yosuke,He, Honglin,et al. Climate-induced changes in sediment supply revealed by surface exposure dating of Sijiquan River terraces, northeastern Tibet[J]. GEOMORPHOLOGY,2015,235:15-26.
APA	Shirahama, Yoshiki.,Miyairi, Yosuke.,He, Honglin.,Fu, Bihong.,Echigo, Tomoo.,...&Ikeda, Yasutaka.(2015).Climate-induced changes in sediment supply revealed by surface exposure dating of Sijiquan River terraces, northeastern Tibet.GEOMORPHOLOGY,235,15-26.
MLA	Shirahama, Yoshiki,et al."Climate-induced changes in sediment supply revealed by surface exposure dating of Sijiquan River terraces, northeastern Tibet".GEOMORPHOLOGY 235(2015):15-26.