Abstract: Interferometric synthetic aperture radar (InSAR) is widely used in geological hazard monitoring and urban subsidence analysis as a technology that can obtain large-scale and high-precision surface deformation data.However,the existing WebGIS platform has obvious deficiencies in the efficient display,query and interpretation of tens of millions of InSAR point cloud data and deformation time series data,which restricts the promotion and application of InSAR technology.Therefore,in order to solve the key technical problems such as data preprocessing,storage,browsing and query of InSAR point clouds,this paper proposes a set of efficient visualization and query methods for massive InSAR point clouds in the Web environment,and develops a prototype system based on Cesium.By testing the performance of the system in six typical application scenarios,the results show that the developed system can smoothly realize the display of 3D deformation sequences of tens of millions of InSAR point clouds.The prototype system not only realizes the convenient distribution of InSAR deformation data and users can view it online,but also realizes the practical functions of deformation rate profile query,multi-period deformation profile query,single-point time series query and early warning analysis,which provides technical support for surface settlement analysis.

Key words: InSAR, surface subsidence, massive point cloud data, visualization, Cesium