对龙羊峡形成的初步认识

The primary perspective of Longyang Gorge formation

从地貌和新构造的角度实际考察了龙羊峡,建立了共和盆地和龙羊峡地区构造抬升和变形的几何模型。根据模型笔者认为,黄河溯源侵蚀到达贵德盆地之后,龙羊峡西段由海拔3000m的夷平面封闭共和古湖,共和盆地周围的水体流向共和古湖;峡谷东段拉吉玛、罗汉堂地区已进行溯源侵蚀,水体向东流向贵得盆地。共和运动发生时,共和盆地作为一个完整的次级刚性活动块体被向东挤出和向东南微量顺时针旋转,同时,盆地的西端垂直构造抬升的幅度大于东端,共和古湖的水体重心向东偏移,水面越过海拔3000m的夷平面,向东流向贵德盆地,流水作用在两个盆地之间快速下切形成现今的龙羊峡。

On the basis of the field geologic, geomorphic, active tectonic observation and much more indoor research , we propose a dynamic model for the tectonic uplift and deformation of Gonghe basin and Longyang Gorge region. Modeling suggests that the ancient Gonghe lake was closed by the planation surface of 3000m height above sea level in the west part of Longyang gorge after the getting of deriving erosion of Yellow river to Guide basin, around the Gonghe basin, the fluid flowed to the lake ;The east part of Longyang Gorge in Lajima and Luohantang area had been eroded to source, the fluid flowed to the Guide basin. When Gonghe movement took place, Gonghe basin,as a complete secondary rigidity active block, was extruded to east and rotated clockwise to southeast for little scale.Besides this,as its vertical uplifting displacement of west part was bigger than east the water barycenter of the ancient Gonghe lake deviated from west to east.So the water surface got across to 3000m planation surface, the water of ancient Gonghe lake flowed to Guide basin, then, Longyang Gorge had been formatted by the fast incision with the fluid between Gonghe basin and Guide basin.