Earthquakes in Rome during the past one hundred years

We have studied the seismic response of the city of Rome using the available macroseismic data of local earthquakes which occurred during the past one hundred years. These earthquakes were generated by three dislinct seismogenic sources falling within the present extent of Rome. The comparison with the effect produced in Rome by a large Apennine earthquake (January 13. 1915) suggests that the damage patterns are similar and that they are mainly controlled by the local geology and morphology. The analysis shows that most of the damage was concentrated in buildings located on alluvial deposits of the Tiber River rather than in buildings underlain by different lithologies. In addition, the largest concentration of heavy darnage occurred in buildings located on the alluvial deposits of the right-hand side of the Tiber River valley, and particularly where the buried interface between Holocene and Pliocene deposits is steepest. This close relationship between damage pattern on the one hand, and geology and geometry of the shallowest deposits on the other hand, supports the results of ground motion modeling studies of the same area and similar observations collected in different regions of the world during large earthquakes.