The SantʹAgata Feltria landslide (Marche Region, central Italy): a case of recurrent earthflow evolving from a deep-seated gravitational slope deformation

This paper examines the evolution of a large-scale earthflow located in the northern sector of the Marche Region (central Italy). In this area, mass movements of different typology are particularly frequent since geological and geomorphological conditions often favour slope instability. these many mass movements, the one affecting the historical village of SantʹAgata Feltria has been chosen, also because its evolution has been recorded in chronicles starting from ancient times. In fact, reactivations of the 5.4 km long earthflow crossing the village have been quoted at least 12 times starting from the 16th century, even though more ancient activations have been inferred. ic researches and geomorphologic analyses allowed the detailed reconstruction of the evolution and the mechanism of the phenomenon, outlining its causes and delineating risk zonation. In particular, a deep-seated gravitational movement (lateral spreading) marked by trenches and ponds has been recognised at the top of the landslide. The earthflow has been interpreted as a more surficial side-effect of the deep-seated phenomenon, which constitutes its source area. also been highlighted that reactivations coincided with long-lasting and intense rainfalls whilst no direct connection seems to exist with earthquakes, even though the area is seismically rather active and seismic shocks could have been among the major triggering factors for the deep-seated deformation. dest (and probably most catastrophic) recorded event itself (1561 A.D.), took place during the first stages of a period of severe climate that involved the whole of Europe.