A new method for the time-variant seismic wavelet estimation

To widen the subsection stationary assumption of the seismic wavelet in common sectional method for time-variant wavelet estimation, the time-variant mixed-phase seismic wavelet estimation method based on spectral modeling in time-frequency domain is proposed. The seismic record is transformed into time-frequency domain using the improved generalized S-transform firstly. After filtering the time-frequency spectrum in time-frequency, the amplitude spectrum of the time-variant wavelet is estimated using spectral modeling method at every moment. With the assumption that the wavelet phase is time-invariant, mixed phase is estimated by the bispectrum from the proposed seismic record of no wavelet amplitude. Then the time-variant mixed-phase seismic wavelet is received by combining the estimated amplitude spectrum and phase spectrum. Theoretical analysis and synthetic example results show that the method is effective and feasible.