New Findings and Dating of Lacustrine Sediments in the Xishanzui Subuplift, Hetao Basin
详细信息
- 责任者：Fan Tianlai (MOE Key Laboratory of West China’s Environmental Systems ; Lanzhou Universsity ; Lanzhou 730000 ; China) ; Fan Yuxin
- 刊名：Acta Geographica Sinica
- 出版年：2011
- 卷期：66(5)
- 关键词：第四纪 ; Quaternary ; 湖泊沉积物 ; lake sediments ; 河套盆地 ; Hetao Basin
- 页码：p.698-708
- 图表：illus., 1 table, 43 refs.
- 分类号：1400
- issnNo：ISSN0375-5444
- isbnNo：CN11-1856/P
摘要
A complete sedimentary profile composed mainly of typical lacustrine sediments including beachrock and cut-and-built platform located in the Xishanzui subuplift, Hetao Basin, has been found. The geomorphological and stratigraphic evidence indicates that there was a paleolake with its highest lake up to 1080 m a.s.l. Stratigraphic analysis of the profile indicates that this subuplift experienced an environmental change from a deep lake to a shallow lake and then to non-lake environment (suggested by alluvial/diluvial sediments). Optical dating results support that Xishanzui subuplift was actually covered by a deep water lake, potentially the Megalake"Jilantai-Hetao"at around 65 ka BP when the lake reached its highest level. And no lake level has exceeded the highest level inferred from sedimentary sequence in the profile.