Quantifying the effectiveness of stabilized inverse Q filtering

摘要

Applying inverse Q filtering to surface seismic data may minimize the effect of dispersion and attenuation and hence improve the seismic resolution. In this case study, a stabilized inverse Q filter is applied to a land seismic data set, for which the prerequisite reliable earth Q function is estimated from the vertical seismic profile (VSP) downgoing wavefield. The paper focuses on the robust estimate of Q values from VSP data and on the quantitative evaluation of the effectiveness of the stabilized inverse Q filtering approach. The quantitative evaluation shows that inverse Q filtering may flatten the amplitude spectrum, strengthen the time-variant amplitude, increase the spectral bandwidth, and improve the signal-to-noise (S/N) ratio. A parameter measuring the resolution enhancement is defined as a function of the changes in the bandwidth and the S/N ratio. The stabilized inverse Q filtering algorithm, which may provide a stable solution for compensating the high-frequency wave components lost through attenuation, has positive changes in both the bandwidth and the S/N ratio, and thereby enhances the resolution of the final processed seismic data.