Research of compensation method for formation Q value based on HHT method

The conventional Q-value compensation method based on post-stack seismic data is affected by the data average effect, and the estimation accuracy of Q value is always low that results in poor fidelity. Fortunately, the HHT time-frequency analysis may reflect the local information of the signal. Therefore, this paper proposed a formation Q-value compensation method based on HHT. First, using the HHT spectral decomposition technology to divide the shallow, medium and deep seismic data into different frequency ranges, and the seismic data for different target layer frequency scales are acquired. Then, the Q value is extracted with spectral ratio method from the HHT time-frequency domain, and finally, the formation Q amplitude compensation and phase compensation are respectively realized. The method may decompose seismic data into different frequency scales for different target strata, avoid interference between different frequency information components, effectively deal with the frequency information of the target layer, and improve the stability of formation Q value extraction. Trial model calculation and practical data application demonstrate that the method can effectively compensate the amplitude and phase, restore the mid-deep reflection waveform, improve the main frequency, widen the frequency band, and improve the quality of seismic data.