MONITORING AND ASSESSING THE STATE OF ACTIVITY OF SLOPE INSTABILITIES BY THE PERMANENT SCATTERERS TECHNIQUE

Abstract

The evaluation of the state of activity is an essential step for landslide hazard assessment. To attribute a state of activity class to a landslide a suitable set of monitoring data is needed. Different types of landslides present different characteristics and are subjected to different spatial and temporal evolution; these become relevant when working at a regional scale or when a catastrophic evolution of the movement is expected. The Permanent Scatterers (PS) technique is used to determine state of activity and long term behavior of rock slope instabilities. The PS technique, overcomes several limitations of conventional differential SAR interferometry (DInSAR) applications, and proves to be effective for high accuracy monitoring of gradual very slow slope deformation which may eventually transform into extremely rapid failures. The success depends on various factors including: available data, location and morphology of the area, PS density; and motion of the targets. We present the results of the application of the technique at a regional scale in the Central Italian Alps involving different types of instabilities in different materials. The utility of the technique in landslide hazard assessment is demonstrated by the quality of the results and by theintegration of different datasets (inventory maps, site investigations, remote sensing).