Rainstorm-induced Geological Hazard Monitoring And Assessment

Rockslide induced by rainstorm often has the characteristic of suddenness and is difficult to suvey in the mountain area.Therefore,it is not only difficult to achieve real-time,but also difficult to ensure authenticity and accuracy if we use the the traditional methods of investigation and monitoring in this case.With the rapid development of RS technology and GIS technology,it is possible to use multi-temporal RS images to monitor the real-time condition of geological hazard.On this basis,combined with the geological environment,data analysis and GIS technology,we can improve the predictability of the geological hazard by identifying the spatial discipline of geological hazard,so as to provide accurate information for the prevention and relief work of geological hazard,further more,promoting national economic construction and sustainable development.Three Gorges reservoir area is located in the transition of the mountain canyon area between Chongqing and Hubei province which has more steep slope,arable land and dense population,complex geological conditions,especially is in the subtropical zone of frequent rainstorm.These factors play a vital role to the preparation and occurrence of rockslide and landslide.In this paper,we made Chongqing City Zone of Three Gorges reservoir area as the study area,analyzed and forecasted the hazard of rockslide with a large number of detailed spatial data and attribute data in this area.The research mainly obtained following achivements:(1)Discoursed in detail the key RS technology involved in the rockslide interpretation research.Discussed the selection of RS image,band combination,image enhancement,geometric correction and three-dimensional modeling of such image processing technology and its implementation methods.(2) The study area was established for the interpretation signs of rockslide by the reference of previous research.It made August 2,2009-August 6,2009 this heavy rain process occurred in Chongqing city as the interpretation time and was interpreted maily by the QuickBird high-resolution RS image and CBERS-02 as auxiliary image.The paper interpreted rockslide induced by the rainstorm in the heavy rain process and found the the spatial distribution condition of rockslide by comparing RS images before and after the rainstorm in the study area.(3) Simply analyzed the relationship between the rockslide and rainstorm.Considering with the geological environment,the paper maily selected elevation,slope,stratum and lithology,geological structure,rivers,roads,vegetation cover these (?) pregnant hazard factors as evaluation factors,then got the correlation between these factors and rockslide with the help of GIS zonal statistics.Afterwards,combined closely with the engineering geological conditions and formation mechanism of rockslide,this research.applied the information quantity model to the rockslide hazard assessment to find the contribution degree for the specific attribute zone of each factor to the rockslide.The analysis result conincide with the development status of geological hazards which Shows that the evaluation model is reliable and the research achievements have a certain use value.