Integrating geomorphology, statistic and numerical simulations for landslide invasion hazard scenarios mapping: An example in the Sorrento Peninsula (Italy)

• We developed an integrated approach for debris flow invasion hazard scenarios.
• Spatial, magnitude and temporal probabilities and runout were assessed.
• The SCIDDICA model was able to well simulate the considered case studies.
• The validity of the approach is related to the quality and accuracy of input data.
• By varying statistical hypotheses, different hazard scenarios can be mapped.

This paper highlights a multidisciplinary method for evaluating debris-flow invasion hazard, based on geological–geomorphological field survey and statistical analysis coupled with numerical simulations through Cellular Automata. The developed hazard assessment methodology consists of different consolidated techniques for the (a) identification of spatial susceptibility, i.e. potential landslide sources in previous unfailed slopes, (b) estimation of the probability of cover thickness involvement in initial landsliding, (c) evaluation of temporal probability and (d) numerical modeling of potential landslides. In this study, the SCIDDICA Cellular Automata landslide model has been considered and applied to the northern sector of Mount Pendolo (Sorrento Peninsula), which was affected by several landslides in historical time. Model calibration has been performed by considering past events of similar scale and type. Results of these simulations were satisfactory as proven by the comparison between real and simulated reference events. Several possible source areas have been hypothesized and a potential future landslide scenario has been simulated by using SCIDDICA. By associating to each simulation a spatial, magnitude and temporal probability, a landslide invasion hazard scenario was mapped.