Publication Date:
2016-10-16
Description:
On 24 th August 2016 a magnitude M L 6.0 occurred in the central Apennines (Italy) between Amatrice and Norcia causing nearly 300 fatalities. The mainshock ruptured a NNW-SSE striking, WSW dipping normal fault. We invert waveforms from 26 three components strong motion accelerometers, filtered between 0.02-0.5 Hz, within 45 km from the fault. The inferred slip distribution is heterogeneous and characterized by two shallow slip patches up-dip and NW from the hypocenter, respectively. The rupture history shows bilateral propagation and a relatively high rupture velocity (3.1 km/s). The imaged rupture history produced evident directivity effects both N-NW and SE of the hypocenter, explaining near-source peak ground motions. Fault dimensions and peak slip values are large for a moderate-magnitude earthquake. The retrieved rupture model fits the recorded ground velocities up to 1 Hz, corroborating the effects of rupture directivity and slip heterogeneity on ground shaking and damage pattern.
Print ISSN:
0094-8276
Electronic ISSN:
1944-8007
Topics:
Geosciences
,
Physics
