Debris-flow hazard assessment applying the resistivity imaging method: case study of Cancia (Dolomites, northeastern Italy)

The debris-flows which occurred in the area of Cancia (Dolomites, North-East Ita-ly) in recent years caused serious risk situations for the population. This fact led to the installa-tion of an alarm and monitoring system in 1996 with the aim of providing a sufficient level of sa-feguard for the inhabitants and infrastructures. In order to assess the debris-flow hazard and to realize a hazard map of the area, the method of Earth Resistance Tomography (ERT) has been applied. ERT represents an exhaustive geophysical prospecting tool to estimate the volumes of the materials being mobilized and the morphology of the bedrock. Using the results of geophysi-cal investigations it has been possible to delineate a subsurface geological model that helped in the production of a hazard map following the risk assessment procedure proposed in the Swiss method (Heinimann et al., 1998). The method demonstrated to be consistent with these criteria.