Landslides Triggered by Recent Earthquakes in Italy

This document provides a detailed description of seismically-induced landslides and rockfalls that occurred in Italy during the 2016 Central Italy earthquake sequence. Relevant ground motion characteristics for all mainshocks of the sequence are analyzed. The document also provides a quantitative overview of spatial and temporal characteristics of the landslides and rockfalls that occurred during the earthquake sequence which was characterized by three mainshocks: (1) M6.1 on 24 August, (2) M5.9 on 26 October, and (3) M6.5 on 30 October. A relevant fraction of landslides has been caused by the first M6.1 mainshock; however, both the following events, especially the third M6.5 earthquake, exacerbated the slope instability in many locations and triggered several new and more serious ground failures. The overwhelming majority of the instabilities induced by the sequence are rockfalls in fractured rocks. Details of three selected case histories are described: (1) the Nera rockslide, (2) the Pescara del Tronto landslide, and (3) the Accumoli landslide. Rainfall data during 2016 are also shown and described for selected locations in the epicentral area