New insight on the seismic hazard of Monterubbiano (Marche Region)

Within the project PROCULT (Probabilistic performance-based methodology for seismic risk assessment of cultural heritage), funded by the University of Camerino (FAR 2012), the research activities of the Group 1 “Seismology and geotechnics” are focused on the evaluations of the seismic hazard of the area where the Convent of San Francesco in Monterubbiano (representing the selected case study of the Project) is located. In this work we present the results concerning the reconstruction of the seismic history of the study area through the analysis of the historical and instrumental seismicity. This reconstruction allowed us to individuate three seismic source zones characterized by a different seismic behaviour. The first zone is located astride the provinces of Macerata and Fermo and is characterized by a diffuse both shallow (<15 km) and relatively deep (15–25 km) small-magnitude earthquakes. Here, the last seismic sequence occurred between 10 and 12 January 2010 (Loro Piceno seismic sequence) when more than 400 events with magnitude values between 0.7 and 4.2 were recorded. The second zone, located to the east of Monterubbiano along the coast line, is characterized by medium size earthquake as the 1480 (Mw 5.4, Monteprandone) and the 1987 (Mw 5.1, Porto San Giorgio) earthquakes. In the last zone, located to the south with respect to the study site, were recorded the strongest earthquakes: the 100 B.C. (Mw 5.8, Picenum) and the 3 October 1943 (Mw 5.8, Offida) seismic events. On the base of these results, future work will be addressed to estimate the seismogenic faults parameters characterizing the three different zones and to construct the relative geological and structural models in order to evaluate the correct seismic input for the Convent of San Francesco in Monterubbiano. In this contribution is presented a seismic hazard assessment using both deterministic and probabilistic approaches, as proposed by Sabetta (2014).