Technique and Application of Near-Surface Q Estimation and Compensation

Absorption & attenuation is one of the main factors to lower the seismic data resolution and the absorption & attenuation of near surface is much more serious than that of the subsurface. Because near-surface Q model is very difficult to establish, conventional absorption compensation technique always aims at how to compensate the subsurface strata Q effects and seldom considers the near surface effects. This paper introduces a method to establish near-surface Q model by joint application of uphole and seismic data, and then wavefield continuation with fine gain controlled of Q compensation is used to pre-stack seismic data to recover the absorption & attenuation of near surface. With these methods consistency of seismic signal waveform and phase is enhanced, frequency bandwidth is broadened and resolution is improved that show our method is effective and practical.