| Abstract: | A detailed statistical analysis applied to the seismicity of Italy and surrounding areas allows us to identify some correlations between several statistical parameters and the thickness and the elastic parameters of the lithospheric part of the mantle, the lid. In particular, the intensity of the flow of seismic events, deprived of aftershocks, shows concentrations in relation to large gradients in the lithospheric thickness, due to abrupt variations of the lid thickness. When this variation is not very large the intensity of flow of seismic events is smaller than on the average, but in these areas (e.g., the Calabrian Arc) the strongest shocks tend to occur. The average depth of crustal shocks tends to be very shallow in relation to the thin and soft (low shear-wave velocities) lid. The positive influence, probably reflecting the thermal state in the lithosphere, is very large in relation to the thin and soft lid and where strong gradients in lid thickness are observed, and is small in relation to thick and hard lid (high shear-wave velocities). From the observed correlation between seismicity properties and lid characteristics, it may be concluded that aseismic slip below the Moho might be a key seismogenetic process. |
