Abstract:In seismic exploration, surface wave is considered as a noise, and needs to be suppressed. We propose in this paper a surface wave suppression method with polarization filtering based on the generalized S transform. On one hand, we remould the window function of S transform, and improve the frequency resolution of seismic signal by increasing the regulatory factors to implement nonlinearly variable window function with the frequency. On the other hand, we construct the cross-energy matrix in time-frequency domain using the generalized S transform, compute instantaneous polarization attributions through eigenanalysis and design filter algorithm in the time-frequency domain to achieve multi-component seismic polarization filtering. The specialties of this method are that the time window length of covariance matrix is determined by the instantaneous frequency of multi-component seismic data. And it can adapt with the dominant period of the desired signal. Meanwhile, it calculates polarization parameters at each time-frequency point and no longer needs to undertake the interpolation. Processing results of model data and real three-component data show that surface wave is well removed by the proposed method, and high resolution data is obtained.
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