GNGTS 2023 - Atti del 41° Convegno Nazionale

Session 1.1 GNGTS 2023 Figure 3. Sketch of the faulted house in Capo del Colle. The AMS age inside the dragged and faulted foundation ditch, together with tiles and pottery shards, indicates that the surface faulting is post 1488-1650 AD, and thus attributable to the 1703 earthquake. Conclusions For the first time, we have shown the historical surface faulting of both the Norcia and Campi master faults, which had just been supposed so far. The new paleoseismic data collected for these faults evidence the contemporary rupture of the two segments during the 1703 earthquake. Considering that even the Cascia-Monte Alvagnano fault - at the southern tip of the Norcia fault (Fig. 1) - ruptured in 1703 (Galli et al., 2019), we can finally assert that the seismogenic source of the January 14, 1703 event is the entire Norcia fault system. AMS dating of key samples in the Norcia trenches strengthens the possibility that even the 99 BC earthquake - which was known only through elusive Classical sources and archaeoseismic indications - was generated by the Norcia system. We don’t know if Nick died in the 99 BC earthquake, but he was really buried next to the fault; he will remain the first man to be found in a paleoseismological trench in the World. References Galli P., Galadini F.; 1999. Seismotectonic framework of the 1997-98 Umbria-Marche (Central Italy) earthquakes. Seismological Res. Letters, 70, 404-414.