Imaging by Scattered Surface Waves – Preliminary Results From Seismic Field Data

contrast of the heterogeneity by using scattered surface waves. In the method three dimensional elastodynamic wave propagation and scattering in a laterally invariant embedding is considered. The scattered wavefield is expressed as a domain type integral representation. Weak contrast in density is considered and the Born approximation is used. Due to the lateral invariant medium assumption, the radial symmetry of the medium is considered and the Green’s tensor elements are calculated in an efficient way. The method is verified by numerical tests and by a scale model experiment. Preliminary results of the seismic field data are obtained. The location and the size of the tunnel are reasonably well estimated and the density contrast is qualitatively estimated. The estimation of the actual density contrast is in progress.