Clues of postseismic relaxation for the 1915 Fucino earthquake (central Italy) from modeling of leveling data

We study five high precision leveling lines located around the epicentral area of 13 January 1915, Mw = 6.7 Fucino earthquake ( Italy), that possibly recorded late stage postseismic relaxation movements. The geodetic signal is expected to comprise both large-scale uplift of the Apennines and postseismic relaxation effects. In order to verify this hypothesis and to estimate the amount of each contribution, we compute gravitational visco-elastic postseismic relaxation by inverting leveling data. Results indicate that the elastic upper crust is relatively thin ( about 10 km) and post-seismic contribution could be set at 30% of the geodetic signal. Model parameters are consistent with previous knowledge of the 1915 Fucino earthquake source, local seismic hypocentral determinations and crustal models derived from surface waves.