Assessing shallow debris slide hazard in the Agnano Plain (Naples, Italy) using SINMAP, a physically based slope-stability model

摘要

In the last 20 years the Agnano Plain, Naples, Italy, has been affected by several shallow landslides in its pyroclastic products. Following a geomorphologic survey, integrated by air-photo interpretation and archival research, a landslide inventory and a database were implemented, consisting of 62 mass movements, 80% of which are represented by shallow debris slides. Based on a DEM with a ground resolution of 5 m x 5 m, the SINMAP code (Pack et al. 1998) was adopted, in order to explain and eventually predict the spatial distribution of the slides. Stability Index (SI) values, calculated as a result of an infinite slope stability model, were used to classify the studied territory in six stability classes. 48 out of the 49 slides considered fell in the regions characterized by the lowest SI (lower and upper threshold slope zones, defended slope zones). Having correctly classified the shallow slides of the Agnano Plain, the SI map created with SINMAP can hence be considered as a reliable tool to mimic the landslide susceptibility of local slopes.