Rayleigh wave velocity and structure of the crust and upper mantle beneath the seas in eastern China

The velocity structure of the crust and upper mantle beneath the seas in eastern China are revealed in this paper by studying the surface wave dispersion. High quality Rayleigh wave data from thirty-one stations are used in this paper. A new grid inversion method (Occam's inversion method) is adopted to calculate the pure path dispersion curves in this area. The group velocity maps of Rayleigh waves are obtained for thirty-six periods from 10 to 150 seconds, and the shear wave velocity structure are constructed for a few locations typical for some tectonic units. The division of different tectonic units and the characteristics of both velocity structure and the depth of low-velocity layer in the upper mantle of different tectonic units in the study area are studied.