Using satellite radar images to investigate the influence of tectonic setting on large slope instabilities

Abstract

The paper focuses on identification of tectonic setting on large slope instabilities in the area of Giudicarie Valley, located in the south-western sector of the Trentino-Alto Adige region (northern Italy), with particular reference to those phenomena inducing a high level of risk. The study area, located in the Southern Alps, shows a complex structural setting, mainly influenced by the south Giudicarie Line and its associated steep to subvertical faults WNW-dipping. Tectonic setting strongly influences the evolution of slopes, it may be considered one of the main cause of the onset of current instability phenomena. Geological, geomorphological, structural and geomechanical field investigations were conducted on Prezzo landslide area (Giudicarie Valley) in order to investigate the relationship between the tectonic setting and the instability. Advanced DInSAR techniques, such as Permanent Scatterers (PS) and Small Baseline Subset (SBAS) algorithms, were applied to ERS 1-2 (1992-2010) and ENVISAT (2003-2010) satellite RADAR images, to detected displacement areas related to geological structural elements which could influence the Prezzo landslide development. Results show that PS and SBAS data interpretation is an helpful tools in investigating the influence of tectonic settings on landslide processes.