Velocity and density of a two-dimensional acoustic medium from point source surface data

An inverse acoustic scattering theory and algorithm is presented for the reconstruction of a two-dimensional inhomogeneous acoustic medium from surface measurements. The measurements of the surface pressure due to a harmonically oscillating surface point source at two arbitrary frequencies allows the separate reconstruction of the density and velocity of the subsurface. This is a first step towards solving the inverse problem of exploration geophyiscs.