• 责任者：Wang Hengsong ( College of Tourism and Environmental Sciences ; Shaanxi Normal University ; Xi＇an 710062 ; China) ; Huang Chunchang
• 刊名：Acta Geologica Sinica
• 出版年：2012
• 卷期：86(6)
• 关键词：黄土 ; loess ; 光释光测年 ; optical stimulated luminescence dating ; 渭河 ; Weihe River
• 页码：p.994-1004
• 图表：illus., 2 tables, 51 refs.
• 分类号：1400
• issnNo：ISSN0001-5717
• isbnNo：CN11-1951/P

Through extensive field investigation, paleoflood stagnant zones were found to occur in layers of the loess--paleosol profiles in the middle reaches of Weihe River. Authors carried out chronological and sedimentological study on the samples collected from the stagnant zones. Analyses of grain- size distribution and magnetic susceptibility for the samples collected from the Holocene strata suggest that the sediments hosted in the profiles are the paleoflood stagnant material and have recorded climatic and hydrological information of paleofloods during that period. Nine Optically Stimulated Luminescence （OSL） ages were obtained using the post IR SAR dating method, indicating that flooding occurred frequently during 3. 2～ 2. 8ka in middle reach of Weihe River. This study then reconstructed the chronology framework of the palaeoflood events in the middle reaches of Weihe River. The results reveal that palaeoflood occurred very frequently at the turning period from the middle Holocene to the late Holocene, during which the climate in the Weihe reaches turned to be dry. The leading reasons for extraordinary palaeofloods were unstable atmosphere system, dramatic changing climate, and variable precipitation.