f Computer simulation of rayleigh waves produced by seismic sources

The effects of ground rolton seismic data are well known: loss of informations, poor signal to noise ratio, and need for costly f-k filtering on shot data. The ground roll in layered media is built up with several vibrational modes, whose features (amplitude spectrum , group and phase vetocity) are strongly dependent on the properties of the shallowest layers of the Barth (AJ-Husseini et al., 1981). If these features are known, It is possible to simulate the ground rolt and evaluate the loss of resolution, and to be able to redesign the acquisition geometry to improve the signal to noise ratio. The target of our research was the development of a simple and fast technique to compute all the relevant features of the ground roll produced by an explosive seismic source, i.e. the phase and group velocity, the noise amplitude vs. frequency, and the time shape and duration of the signal. The results of the simulations were then used to evaluate the effectiveness of seismic acquisition geometries.