Upper Pleistocene-Holocene geomorphic changes dictating sedimentation   rates and historical land use in the valley system of the Chifeng   region, Inner Mongolia, northern China

doi:10.1002/esp.1944

CORC > 北京大学 > 地球与空间科学学院

	Upper Pleistocene-Holocene geomorphic changes dictating sedimentation rates and historical land use in the valley system of the Chifeng region, Inner Mongolia, northern China
	Avni, Y. ; Zhang, J. F. ; Shelach, G. ; Zhou, L. P.
刊名	earth surface processes and landforms
	2010
关键词	loess landscape evolution OSL dating human occupation Chifeng region of northeast China OPTICALLY STIMULATED LUMINESCENCE LOESS PLATEAU ENVIRONMENTAL-CHANGE NEGEV HIGHLANDS GULLY EROSION QUARTZ DESERTIFICATION IMPACT GRAINS ISRAEL
DOI	10.1002/esp.1944
英文摘要	This study focuses on the late Quaternary landscape evolution in the Chifeng region of Inner Mongolia, China, its relations to the history of the Pleistocene-Holocene loess accumulation, erosion and redeposition, and their impact on human occupation. Based on 57 optically stimulated luminescence (OSL) ages of loess sediments, fluvial sand and floodplain deposits accumulated on the hill slopes and floodplains, we conclude that during most of the Pleistocene period the region was blanketed by a thick layer of aeolian loess, as well as by alluvial and fluvial deposits. The loess section is divided into two main units that are separated by unconformity. The OSL ages at the top of the lower reddish loess unit yielded an approximate age of 193 ka, roughly corresponding to the transition from MIS 7 to 6, though they could be older. The upper gray loess unit accumulated during the upper Pleistocene glacial phase (MIS 4-3) at a mean accumulation rate of 0.22 m/ka. Parallel to the loess accumulation on top of the hilly topography, active fans were operating during MIS 4-2 at the outlet of large gullies surrounding the major valley at a mean accumulation rate of 0.24 m/ka. This co-accumulation indicates that gullies have been a long-term geomorphic feature at the margins of the Gobi Desert since at least the middle Pleistocene. During the Holocene, the erosion of the Pleistocene loess on the hills led to the burial of the valley floors by the redeposited sediments at a rate that decreases from 3.2 m/ka near the hills to 1-0.4 m/ka(1) in the central part of the Chifeng Valley. This rapid accumulation and the frequent shifts of the courses of the river prevented the construction of permanent settlements in the valley floors, a situation which changed only with improved man-made control of the local rivers from the tenth century AD. Copyright (C) 2010 John Wiley & Sons, Ltd.; Geography, Physical; Geosciences, Multidisciplinary; A&HCI; SCI(E); EI; 5; ARTICLE; 11; 1251-1268; 35
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/243062]
专题	地球与空间科学学院
推荐引用方式 GB/T 7714	Avni, Y.,Zhang, J. F.,Shelach, G.,et al. Upper Pleistocene-Holocene geomorphic changes dictating sedimentation rates and historical land use in the valley system of the Chifeng region, Inner Mongolia, northern China[J]. earth surface processes and landforms,2010.
APA	Avni, Y.,Zhang, J. F.,Shelach, G.,&Zhou, L. P..(2010).Upper Pleistocene-Holocene geomorphic changes dictating sedimentation rates and historical land use in the valley system of the Chifeng region, Inner Mongolia, northern China.earth surface processes and landforms.
MLA	Avni, Y.,et al."Upper Pleistocene-Holocene geomorphic changes dictating sedimentation rates and historical land use in the valley system of the Chifeng region, Inner Mongolia, northern China".earth surface processes and landforms (2010).