In the flood season of 1987, rockfal and landslide took place for 58 times in succession, but no one is harmed in Zigui county of Hubei Pro vince, which is a wonder created by the Party, the authorities and the masses in rushing to-deal with the emergency and fighting natural cala mities. It is thought that the reason of the collapsing and landsliding is mainly related to the effect of geological structure, topography and geo graphy, the damage of plantation, the intensive rainstorms, unadoptable excavation in construction and the unstable side slope immersed by watern e reservior of Guozhouba Dam, etc.