云南小江流域第四纪泥石流及发育环境

The Quaternary Debris Flow and Its Developing Environment in Xiaojiang Basin, Yunnan

广泛分布的第四纪不同时期泥石流堆积的岩相特征、化学分析结果及孢粉组合和部分绝对年代资料表明,小江流域第四纪泥石流发育于温暖湿润的间冰期(间冰段)的早期,因而存在不同时间尺度的泥石流活动期。泥石流活动主要受控于季风影响下的降水,因而随着气候的变化,泥石流的活动有准周期性的变化,这些周期的时间尺度是不同的,大尺度的活动周期主要受控于全球冰期与间冰期影响下本区气候干湿冷热变化。

According to chemical analysis results, pollen assemblage,partly absolute years,and rockfacies feature of the quaternary debris flow sediment in different period, the quaternary debris flow in Xiaojiang basin formed in interglaciation and interglacial stage with humid and warm environment, therefore,existing debris flow active period of different time criterion. The debris flow action mainly was influenced by pricepitation,with climatic change,it presented periodic variation, time yardstick of these periods was different, its active period of big yardstick mainly has close relation with global climatic change.