resolution. To compare the ALS raster data with the Tis data, the former were upsampled to the TLS raster resolution. To fill cells without data, we used a nearest-neighbour interpolation. The elevation values of multitemporal raster surfaces were subtracted from each other. In the resulting difference-raster, deformations or rapid mass movements could easily be identified. Deposit or erosion volumes were defined by adding up the difference-raster values over a specified spatial extent.