Cosmogenic Be-10 constraints on Little Ice Age glacial advances in the   eastern Tian Shan, China

doi:10.1016/j.quascirev.2016.02.023

CORC > 北京大学 > 城市与环境学院

	Cosmogenic Be-10 constraints on Little Ice Age glacial advances in the eastern Tian Shan, China
	Li, Yanan ; Li, Yingkui ; Harbor, Jon ; Liu, Gengnian ; Yi, Chaolu ; Caffee, Marc W.
刊名	QUATERNARY SCIENCE REVIEWS
	2016
关键词	Cosmogenic nuclides Little Ice Age glacial advances Nuclide inheritance Eastern Tian Shan LATE QUATERNARY GLACIATION NORTHERN-HEMISPHERE TEMPERATURES PRODUCTION-RATE CALIBRATION CENTRAL TIEN-SHAN CENTRAL-ASIA SURFACE EXPOSURE URUMQI RIVER CLIMATE-CHANGE ATMOSPHERIC CIRCULATION TIBETAN PLATEAU
DOI	10.1016/j.quascirev.2016.02.023
英文摘要	Presumed Little Ice Age (LIA) glacial advances, represented by a set of fresh, sharp-crested, boulder covered and compact moraines a few hundred meters downstream from modern glaciers, have been widely recognized in the Central Asian highlands. However, few studies have constrained the formation ages of these moraines. We report 31 Be-10 exposure ages from presumed LIA moraines in six glacial valleys in the Urumqi River headwater area and the Haxilegen Pass area of the eastern Tian Shan, China. Our results reveal that the maximum LIA glacial extent occurred mainly around 430 +/- 100 yr, a cold and wet period as indicated by proxy data from ice cores, tree rings, and lake sediments in Central Asia. We also dated a later glacial advance to 270 +/- 55 yr. However, Be-10 exposure ages on several presumed LIA moraines in front of small, thin glaciers are widely scattered and much older than the globally recognized timing of the LIA. Historical topographic maps indicate that most glaciers were more extensive in the early 19605, and two of our Be-10 sample sites were located close to the ice front at that time. Boulders transported by these small and thin glaciers may be reworked from deposits originally formed prior to the LIA glacial advances, producing apparently old and widely scattered exposure ages due to varied nuclide inheritance. Other published ages indicated an earlier LIA advance around 790 +/- 300 yr in the easternmost Tian Shan, but in our study area the more extensive advance around 430 +/- 100 yr likely reworked or covered deposits from this earlier event. (C) 2016 Elsevier Ltd. All rights reserved.; National Natural Science Foundation of China [41328001, 41230523, 40971002]; National Geographic Society [9086-12]; National Science Foundation [BCS-1303175]; SCI(E); EI; ARTICLE; yli32@utk.edu; 105-118; 138
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/437396]
专题	城市与环境学院
推荐引用方式 GB/T 7714	Li, Yanan,Li, Yingkui,Harbor, Jon,et al. Cosmogenic Be-10 constraints on Little Ice Age glacial advances in the eastern Tian Shan, China[J]. QUATERNARY SCIENCE REVIEWS,2016.
APA	Li, Yanan,Li, Yingkui,Harbor, Jon,Liu, Gengnian,Yi, Chaolu,&Caffee, Marc W..(2016).Cosmogenic Be-10 constraints on Little Ice Age glacial advances in the eastern Tian Shan, China.QUATERNARY SCIENCE REVIEWS.
MLA	Li, Yanan,et al."Cosmogenic Be-10 constraints on Little Ice Age glacial advances in the eastern Tian Shan, China".QUATERNARY SCIENCE REVIEWS (2016).