A Pseudo 3D seismic refraction tomography for exploring archaeological structures

In the seismic refraction method, refracted waves provide the velocity and irregularity of the substratum. In this study, we took advantage of this method to construct 3D images of the refractor subsurface for two rectangular arrays of sources and receivers. The procedure consists of fitting a straight line to the refracted arrival times that pass through each of the cells that discretize the study surface. The slope inverse is the P-wave velocity, and the intercept time allows us to estimate the substratum depth. We applied this method to two archaeological zones where it was necessary to know the structure of the subsoil velocity and the possible presence of anomalies associated with buried constructions. Although the technique does not allow detecting irregularities of surface layers close to the surface, the results show good agreement with the results of the 2D seismic sections. The velocity distribution shows anomalies related to buried structures and lateral discontinuities due to changes in the composition of the materials.