The 1976 Friuli (NE Italy) thrust faulting earthquake: A reappraisal 23 years later

We revisit the 1976 Friuli earthquake sequence by combining hypocenters rel ocation, long period surface wave inversion, field geology and strong motio n modelling. We show that fault-related folding is the main active deformat ion by which the seismic energy was released during the main shock (Ms=6.5) and that some of the surface effects reported in 1976 correspond to widesp read bedding planes displacements induced by flexural-slip folding. The fau lt evolved from blind to semi-blind along strike showing the control Of the inherited structural geology on the fault surface break and rupture arrest . Our fault model produces waveforms that fit the accelerograms recorded in the area.