云南鲁甸地震次生山地灾害分布规律与特征.

At 16:30 on August 3rd, 2014, Ms 6.5 earthquake occurs in Ludian County of Zhaotong City,Yunnan Province, China. Ludian earthquake causes a wide spread of secondary mountain disasters including collapse, landslide, unstable slope, etc. By field investigation and interpretation of remote sensing images, there are 235 secondary mountain disasters, and the area is 8.59 km2. Based on GIS spatial analysis method, relationships between the distribution of secondary mountain disaster and earthquake were explained by secondary mountain disaster center number density and area percentage. The former is defined as the number of secondary mountaindisaster central point per square kilometer; the latter is defined as the percentage of the area affected by secondary mountain disasters. The effects of topography, river and rock on spatial distribution of secondary mountain disasters were discussed with the factors including elevation, slope, aspect, lithology and distance from the river.Secondary mountain disaster center number density is about 0.2 points per square kilometer, and area percentage is about 0.79%. The results show that the arrangement of secondary mountain disaster is controlled by the main fault of Zhaotong-Ludian with NE-orientation,and 63.83% of secondary mountain disasters happen in the region with a distance of 2-8 km to the causative fault; secondary mountain disasters mainly distribute in the areas with the elevation of 1000-1200 mand the slope of 35°-45°; secondary mountain disaster center number density and area percentage are maximum under the slope of 20°-30°; secondary mountain disasters develop mostly in hard rock strata such as carbonate rock, while steep slope secondary mountain disasters develop mostly in soft rock strata; secondary mountain disasters approximately distribute in a line along Niulan River, and the farther away from the river, the lower the probability of occurrence is. [ABSTRACT FROM AUTHOR]