Persistent Scatterer Interferometry (PSI) technique for landslide characterization and monitoring

Dealing with landslide, the availability of long time series of displacement often represents the most effective method to define its state of activity, to observe relationship with triggering factors and to assess the effectiveness of the mitigation measures. Moreover, the presence of a dense grid of measurements is essential to map correctly the boundary of the mass movements, to reconstruct the actual vector of displacement and to identify the deformation pattern. Persistent Scatterer Interferometry (PSI) represents an effective tool to measure landslide displacement, as it offers a synoptic view that can be repeated at different time intervals and at various scales. In this paper, PSI interferometry and conventional ground-based monitoring techniques have been integrated to characterize and to monitor the earth rotational slide threatening the Santo Stefano d’Aveto village in the Northern Apennines (Italy). On one hand, the in situ information recorded by inclinometers can help in defining the actual location of the sliding surface and the involved volumes of material. On the other hand, PSI measurements have allowed better redefining of the boundaries of the landslide, its state of activity and have allowed a better understanding of landslide geometry and kinematics. The integration of ground-based monitoring data and PSI data have provided sound results for landslide characterization.