Abstract: Airborne LiDAR system can quickly obtain 3D point cloud data of large-scale surface with high-resolution,high-precision and can be used for extraction of mine subsidence data.But the error of LiDAR data,surface cover and data processing method will lead to the uncertainty of DEM.Based on the analysis of LiDAR DEM accuracy and uncertainty of the two airborne LiDAR point cloud data in 2009 and 2012 in the study area,an error-related surface based on slope,point cloud density and surface roughness was established by using fuzzy reasoning method.The surface can be used to detect the minimum change threshold of DEM and measure the uncertainty of DEM.With the Bayesian estimation determination and correction based on weight window,the surface deformation information in the study area was obtained.Based on the analysis of the slope correlation,the terrain change information caused by the non-mining subsidence was removed by the mask,and the more accurate subsidence basin information was extracted.Experiments show that this method is suitable for large area mining subsidence monitoring,which can quickly determine the location of subsidence area,obtain the information such as the distribution range,area and volume of subsidence area accurately,and provide a new technical means for mining subsidence monitoring.

Key words: LiDAR, Subsidence, DEM, Uncertainty analysis