ABSTRACT
On September 6, 2002 a large landslide was induced close to the village of Cerda by a Ml = 5.6 earthquake. Landslides are one of the most damaging collateral hazards associated with earthquakes. Some research activities have been devoted to reconstruct the mechanisms of seismically-induced landslides and to predict, in a deterministic way, earthquake-induced ground failure scenarios referred to specific case studies. Local seismic response effects due to impedance contrast between bedrock and landslide deposit, topographical effects and trapped wave modes in fault zone areas, can be regarded as favouring conditions for seismic trigger of landslides. Both the Cerda and Salcito landslides are reactivated by far field earthquakes; the pre-existing landslide masses as well as the geological setting can be regarded as responsible for amplification effects due to the high impedence contrast between the scaly clays, involved in the landslide phenomena, and the calcarenitic and marly bedrocks.
