The Research On Post-earthquake Geological Hazards By Remote Sensing Technology In Northern Mountain Area Of Shifang, Sichuan Province

"5.12" wenchuan earthquake led to massive geological hazards as collapse, landslide and debris flow and so forth. These have caused tremendous losses in the lives and properties of the people in various aspects. This have no parallel anywhere.Research area (Northern Mountain Area of Shifang) is situated in central Longmen Mountain Fracture Zone, where is one of severely affected areas. Strengthen the research on geological disasters after the earthquake have important directive to disaster prevention and reduction. Using remote sensing data of SPOT5, we study of the development and distribution characteristics of post-earthquake geological hazards in Northern Mountain Area of Shifang. The main results obtained are as follows:(1) Compared to conventional ground surveys, Satellite remote sensing images have fast access and high resolution features, and a strong ability to grasp the macro. In this paper, I use the point and area-like interpretation methods and interpretate respectively four major geological disasters after the earthquake such as landslides, avalanches, landslides and lake. Research shows that geological disasters after the earthquake are mainly collapse and landslides. Collapse is accounted for more than 60% of the interpretation of all damages.(2) For disaster characteristics and control factors of collapse, landslide, debris flow, lake and other geological disasters after the earthquake, I revised and improved the identification signs and interpretation methods of remote sensing interpretation of geological disasters after the earthquake. The use of specific examples indicate the role of remote sensing technology in Geological Survey earthquake hazard.(3) This thesis analyzes the formation conditions, developing character ,the indication of deformation and wreckage, and condition of post-earthquake geological hazards as rock fall, landslide, debris flow, and barrier lake, which can provided the scientific information for prevention of geological hazards and project planning.(4) Studying of overlaying analysis on post-earthquake geological hazards of remote sensing image interpretation and possible control factor, I investigate the association of these. The results show that aftershocks, topography, faults, lithology and human engineering activities have the controlling role on the development of the disaster point. It manifests in: the more concentrated the aftershocks and the more nearer away from the aftershocks, the more developed the disaster. Whether terrain can provide suitable temporary Empty hand, decides the amount of geological hazards after the earthquake, and geological disasters after the earthquake are zonal development along faults and fractures. Under the control of Pengguan complex rock, geological disasters of the development after the quake on rock are mainly collapse and landslides. Number was significantly higher than it in other developing regions; In addition, human engineering activities have a major impact on the development of geological disasters after the earthquake.