Q Compensation Method Based On Amplitude Control And Its Application

Seismic waves in subsurface spread, due to ground absorption, scattering and other reasons, the seismic wave energy will be attenuated, seismic wave propagation in different frequency wave propagation speed is inconsistent, high frequency relative to low-frequency spread fast and cause velocity dispersion, and speed dispersion leading to the phase distortion of seismic wavelet. With the high resolution seismic data processing requirements, the amplitude of the high fidelity technology concern, Q compensation is to be accurate amplitude and phase attenuation compensation recovery methods.This paper from the seismic wave attenuation principle, first discussed the seismic wave spherical spreading, non-elastic attenuation, the quality factor Q and the attenuation coefficientαof the mutual relations; then seismic Q compensation of various methods were studied, based on the realization Hargreaves fluctuations Exact Solutions to the absorption of forward modeling of seismic records, the method with absorption of the synthesized seismic records contain information on the complete wave field, its shortcomings is larger than calculated. In addition, we carried out Q compensation algorithm of conventional comparative study, through the study found: For the short duration of the signal, Hargreaves method and variations of the Hale algorithms are able to obtain better compensation effect, but Hargreaves method using Fourier transform and the principle of wave field continuation, in the frequency domain superimposed image, the large amount of calculation; Hale algorithm variant target signal and anti-convolution filter factor calculation, while the amplitude and phase compensation, calculating speed.In practice, we found that Q values of compensation in the compensation process information often appears effective submerged in the background noise. Even if the input data is not noise, too. Therefore, the Q value of the compensation process we have not analyzed the stability, the Q value obtained by analyzing the noise compensation, with the increase of travel time, and the Q value of the size of the direct impact on compensation for the results, but also affect the travel propagation distance. Therefore, we recommend given the results in the actual processing, Q value is selected to be taken "rather big not to small" principle, even if the choice of Q value is too large, resulting in inadequate compensation and we can compensate to make up again Q inadequate compensation. If you choose to Q value is too small, not only will cause excessive compensation, but also lead to travel with the increase of noise occurs too early, cover up useful information.Q value of compensation for the problems, proposed a series of amplitude-based control solution. And a series of numerical simulation, the numerical simulation, and achieved good results, the stability conditions, to suppress the deep noise. And made another first-Q compensation, to conduct a band pass filter method also achieved effective suppression of information highlighting the effect of noise, and make a comparison of two methods, pointing out the advantages and strategic nature, and explains on different data, we should choose different ways to make the best treatment effect, and not select the traditional view that the best approach.Finally, the Q value of compensation for the actual data on a single shot, stacked section processed and compared, the amplitude spectrum, phase spectrum, before and after the contrast. Verify the proposed control of the Q amplitude value based on compensation method is to make high-frequency seismic data amplitude and velocity dispersion compensation of the effective methods.