GNGTS 2019 - Atti del 38° Convegno Nazionale

GNGTS 2019 S essione 1.1 31 trace, by projecting the data location on a baseline. Fault width was measured across-strike, with a 50-m resolution. We finally compared our results with macroseismic and surface faulting observations of previous events on Mt. Etna eastern flank. Results. We map surface faulting for a length of about 5 km, along 3 main sectors, namely the Fleri, Fiandaca and Aci Platani segments. We collected a total of 400 observation points, mainly located along the Fiandaca segment (Fig. 2 and 3). We also documented afterslip during the weeks following the mainshock, in particular affecting the Aci Platani segment. Fig. 1- Left: surface rupture of the December 26, 2018, Mw 4.9 earthquake along the Fiandaca Fault in the southeastern flank of Mt. Etna volcano. Right: recent to historical surface faulting in the same area. The capable faults in the area are also shown, taken from the ITHACA database. Fig. 2 - Earthquake surface rupture across the road (right) and a house (left) located a few meters apart in the vicinity of Santa Maria La Stella; notably, the main rupture is located approximately in the middle of a scarp which is the long- term morphological expression of the fault, already censored and mapped with great detail in the Ithaca Database of ISPRA, available since 20 years ago. In spite of this knowledge, the house, built right on the fault trace, was restored and licensed to be widened just before the event. Following the December 26, 2018, earthquake, the house is no longer habitable, being crossed by severe fractures and slightly tilted.