最近150 ka河西地区河流阶地的成因分析

文章通过对河西地区最近150 ka河流阶地年龄数据的处理,发现存在7个明显的河流阶地发育时期,即150、100、70、40、30、12和6 ka B.P.。经过相关构造和气候资料的论证,文章认为,在150和70 ka B.P.附近形成的两级河流阶地代表了河西地区两期主要的构造抬升,而在100、40、30、12和6 ka B.P.附近形成的5级河流阶地则对应于河西地区5期气候变化事件。

Analysis of Origin River Terraces in Hexi Area since 150 ka B. P.

Through processing the age data of river terraces in Hexi area since 150 ka B.P.,this article discovers that the river terraces formed obviously at seven different periods including 150 ka B.P.,100 ka B.P.,70 ka B.P.,40 ka B.P.,30 ka B.P.,12 ka B.P.and 6 ka B.P.After demonstrated by the correlative tectonic and climatic literature,we hold that the two river terraces formed respectively around 150 ka B.P.and 70 ka B.P.indicate two tectonic uplifts,and the five river terraces formed respectively around 100 ka B.P.,40 ka B.P.,30 ka B.P.,12 ka B.P.and 6 ka B.P.are results of five climatic changes.