STUDY AND APPLICATION OF SEISMIC ATTENUATION BASED ON THE ONE-WAY WAVE EQUATION

摘要

Characteristics of seismic attenuation can effectively reveal the impact of rock absorption on seismic waves in heterogeneous viscoacoustic media. In this paper, based on the one-way wave equation, seismic attenuation is simulated successfully in a nonzero-offset viscoacoustic medium by combining the quality factor Q with the Split-Step Fourier (SSF) wave extrapolation method through the Futterman dispersion equation. In addition, the use of the reflection wave forward propagation theory greatly improves the computation efficiency. Numerical experiments are given to show that the one-way wave method is efficient and can generate a clear and simple wave-field, easing the way of further analysis and the construction of reverse algorithms. Besides, the simulation results also reveal the influence of quality factor Q on the seismic wave, such as the wave's shape, energy, frequency, etc. Finally, applying this numerical tool to weak seismic response records of an actual reservoir covered by a high-speed gypsum-salt layer, the reservoir is identified effectively by using complete analysis of attenuation characteristics.