All kinds of geological disasters are easy to occur along the Dadu River in Sichuan, China. The hidden spots of the geological disasters have amounted to 2212, and the geological disasters are debris flow and landslide. The quantity of debris flow is 756, that of landslide is 801, that of collapse is 301, and that of the latent unstable slope is 354. The collapses are mainly distributed along the Dadu River upstream and influenced by the geologic structure. The collapses relatively develop few along the Dadu River middle reaches. They are related with the lithological character closely and are mainly distributed over dolomite, granite and marble areas. But along the downstream, because of the gentle topography, only few debris flows develop in the basalt area. The landslide is mainly distributed along the upstream of the Dadu River. The landside mass consists of glacial tills and slope sediments primarily. It is very difficult to find the penetration sliding surface. The sliding is primarily creeping motion distortion. The landslides most grow along the middle reaches, mostly in the Xigeda Group strata, the battie clamps strata and so on slate and coal bed. There are few landslides along the downstream. They mainly grow in the purple-red sandstone area. The debris flows are mainly distributed along the middle and upper reaches Danba to the Shimian section of Dadu River; there are plentiful source, the terrain, the rainfall and the catchment. Along the middle and lower reaches, there are relatively few debris flows, most caused by the human project activities. Because along the downstream, the topography is relatively gentle and there is not very good catchment condition, the debris flow does not grow.%大渡河流域为中国地质灾害高易发区,目前发现地质灾害隐患点2212处,以滑坡和泥石流为主,其中滑坡801处,泥石流756处,崩塌301处,潜在不稳定斜坡354处.滑坡沿大渡河发育极不均匀,上游较发育,滑坡体主要为冰碛和崩坡积物,以蠕动变形为主;中游滑坡最为发育,多发生于昔格达组、碳质页岩夹板岩和煤层等地层中；下游最少,主要发育于紫红色砂岩地区.泥石流主要分布于大渡河中上游的丹巴至石棉段,中下游泥石流相对较少,多为人类工程活动弃碴引起;下游地势相对平缓,泥石流不发育.崩塌主要分布在大渡河上游,丹巴5条应力释放带和瓦斯沟两岸;中游崩塌相对较少,与白云岩、花岗岩和大理岩关系密切;下游在玄武岩地区有少量发育.
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