Seismotectonics and landslides of the Crati Graben (Calabrian Arc, Southern Italy)

The Crati Graben is a depression of Plio-Holocene age mainly controlled by extensional N–S striking faults and WNW–ESE transcurrent faults, in its northern and southern extremity. It is characterized by high landslide susceptibility due to the particular geo-structural pattern and seismotectonic characters. Landslides involve many villages, infrastructure and food crops, bringing serious economic and social damage. The seismotectonic and landslides Main Map of the Crati Graben, described in this paper, represents an update in detail of the framework of landslide risk areas and shows the main active and recent faults of the Crati Graben. The landslides and the faults, have been identified and classified, originally at detail scale (1:5000) and, then, represented at 1:50,000 scale. The geo-structural and geomorphological data were analysed in a geographic information system. The work has revealed a correlation between the trend of faults with respect to the distribution of landslides and of the historical and instrumental seismicity. The work presents an updated knowledge framework of risk conditions of the study zone, where risk areas related to slope instability are hierarchically classified according to the destructive potential of landslides. This document may be therefore a useful reference in planning and prioritising in the design of interventions for the safety of slopes and waterways.