Combining remote sensing techniques with numerical modeling for the runout analysis of shallow rapid landslides

The aim of this research project is to improve the ability to forecast the propagation of shallow and rapid landslides through the combination of remote sensing and advanced methods of numerical modelling techniques. The activities carried out during the PhD have been done in order to achieve three objectives: - to define the procedures and methods of numerical analysis of the propagation of shallow rapid landslides, through the use of existing codes that allow to model the post- failure behaviour dynamic; - to use remote sensing data derived from LiDAR images (aerial or terrestrial) or radar monitoring data (in particular GB-InSAR), to obtain information about the geometric and geomorphological features of the landslides and to find new future sources areas that can be used with numerical models in order to obtain new risk scenarios; - to use abovementioned the new procedure on case studies of high-risk landslide. Two numerical modelling DAN-W and DAN-3D (Hungr, 1995 McDougall, 2006) are used, based on Lagrangian numerical method to solve the equations of St. Venant. Consider the mass as an "equivalent fluid", governed by an internal frictional rheology and basal rheology that must be chosen with back analysis by trial-and-error procedure. These parameters are then used to forecast analysis using new source areas with new volumes obtained by LiDAR and GB-InSAR monitoring data analysis. The latter, in particular, are processed through a numerical code developed in the MATLAB language. The MATLAB code uses the cumulative displacement maps relative to a selected time interval, to calculate possible sources areas according to a threshold and finally analysed the frequency of movement occurrence. This procedure has been applied at four case studies: gravity induced-Pyroclastic Density Currents (gi-PDC) that take place on the side of Stromboli volcanic island; Mount Rotolon debris flow; Gessi-Mazzalasino debris slide and Santa Trada rock/debris slide.