Study on landslide hazard zonation based on factor weighting-ratingin Wan County, Three Gorges Reservoir area

摘要

Multi-source earth observation data is highly desirable in current landslide hazard prediction modeling, as well asLandslide Hazard Zonation(LHZ) is a very important content of landslide hazard prediction modeling. In this paper,take Wan County for instance, we investigate the potentials of derivation from multi-source data sets to study landslidehazard zonation based on the ordinal scale relative weighting-rating technique. LHZ is then performed with chosenfactor layers including: buffer map of thrusts, lithology, slope angle and relative relief calculated from DEM, NDVI,buffer map of drainage and lineaments extracted from the digital satellite imagery(TM). Then Landslide Hazard Index(LHI) value is calculated and landslide hazard zonation is decided by slicing LHI histogram. The statistics resultsdemonstrate that high stable slope zone, stable slope zone, quasi-stable slope zone, relatively unstable slope zone,unstable slope zone and defended slope zone account for 2.20%, 14.02%, 39.88%, 28.27%, 12.17% and 3.47%respectively. Then, GPS deformation control points on the landslide bodies are used to verify the validity of the LHZtechnique.