Lithosphere density model in Italy: no hint for slab pull

The lithosphere–asthenosphere system of the Italic region in terms of shear-velocity and density distribution with depth is suitable to investigate the geodynamic context of the region. The velocity structure is obtained through nonlinear inversion of dispersion curves compiled from surface wave tomography on cells 1 · 1 and a smoothing optimization method to choose the representative cellular model, whose layering is used as fixed (a priori) information to obtain a density model by means of linear inversion of gravimetric data. Seismicity and heat flow are used as independent constraints in outlining both the crustal and the seismic lid thickness; the nonlinear moment tensor inversion of recent damaging earthquakes allows some insight in the ongoing kinematic processes. Asymmetry between west-directed (Apennines) and east-directed (Alps, Dinarides) subductions is a robust feature of the velocity model, while density model reveals that slabs are not denser than the ambient mantle, thus supplies no evidence for slab pull.