Surface Waves - Use Them Then Lose Them

The coherent noise in seismic data consists mainly of surface waves propagating in the near surface from sources to receivers. The type and properties of surface waves depend on the elastic properties of the shallow subsurface, whose lateral variations and heterogeneities strongly affect surface wave behavior. In conventional land seismic technology, surface waves are considered coherent noise to be attenuated as early as possible in the processing. On the other hand, with wide-band, point-receiver data, surface waves are properly sampled, and can be analyzed to evaluate the 3D distribution of surface wave properties. The inversion of surface wave properties contributes to the building of a near-surface model to be used in data processing, for velocity modeling, perturbation corrections, and others. The identification of their properties allows the use of tailored filters and of an optimized parameterization for better noise attenuation and signal protection.