Characteristics and Distribution of Thick Overburdens along the Dadu River Valley

• 责任者：Xu Qiang (State Key Laboratory of Geo-Hazard Prevention and Geoenvironment Protection ; Chengdu University of Technology ; Chengdu 610059) ; Chen Wei
• 刊名：Quaternary Sciences
• 出版年：2010
• 卷期：30(1)
• 关键词：河谷 ; valleys ; 河流沉积物 ; stream sediments ; 四川 ; Sichuan Province
• 页码：p.30-36
• 图表：illus., 3 tables, 25 refs.
• 分类号：1400
• issnNo：ISSN1001-7410
• isbnNo：CN11-2708/P

Based on borehole data mainly from the construction sites of hydropower stations，the authors studied the distribution，composition，structure and forming time of such overburdens along the Dadu River valley and approached their forming mechanisms. The overburdens are generally more than 30 meters thick and cover about 95% of the Dadu River valley. They consist of superimposed sediments of different origins formed at different times. They can be classified into three main layers in terms of forming time and origin. The forming time is 10 to 30 thousands years ago, which largely corresponds to the last glaciation and then glacial melting. In order to understand the regional characteristic of thick overburdens and in incised valleys in West China，the authors proposed a view that they can be interpreted by global climate change and eustacy (sea level up and down) as a factor.