Rayleigh wave phase velocities and upper mantle structure in the Apennines

Abstract

The dispersion of the phase velocities of the surface Rayleigh<br />waves on the path between the station pair Torino-L'Aquila in the<br />Apennines has been observed with long period seismic stations for twin<br />earthquakes.<br />The inversion was provided by the "Hedgehog" program of non-linear<br />inversion analysis.<br />The interpretation supports the notion that in the Apennines low-velocity<br />material in the mantle is found within a few km of the Moho and may<br />lie immediately below the Moho; however the alternative model of a highvelocity<br />lid and very low-velocity channel cannot be completely rejected.