Distribution Regularity and Regionalization of Geological Hazards in the Upper Yellow River Valley
黄河上游地区地质灾害分布规律与区划

The region of the upper Yellow River valley is one of the areas in China where geological hazards frequently occur. The geo logical hazards mainly include earthquake,collapse,landslide,mud rock flows and soil erosion, land desertification,soil salinization, moisture sedimentation of clay and freezing melt. They not only threat the safety of people's life and all kinds of engineering but also destroy the land resources and ecological environment. They are adverse factors affecting the great exploitation and continuous deve lopment of western China. Geological hazards are different from area to area because they are controlled by such factors as geology, landform and climate. Three typical regions of geological hazards can be recognized: the northern region where there mainly exist soil desertification, soil saliniztion and earthquake; the middle region where earthquake collapse, landslide, mud rock flows and soil erosion are mainly seen; the southwestern and northwestern region where freezing melt is predominant.These regions can be further divided into 13 subregions.