A study on anisotropy of shale using seismic forward modeling in shale gas exploration

The accuracy of numerical methods is challenged by strong anisotropies shown by shale, especially for high-frequency components (>100 Hz). Since the shale gas exploration still employs the acoustic seismic data, we first introduce an artificial even-order differential solution to VTI acoustic wave equation in the paper. The high-order solution can improve the computational accuracy and suppress numerical dispersion effectively. To show the effect of strong anisotropy of shale, we compare the seismic response of VTI acoustic wave equation with that of acoustic wave equation for different models. Numerical results show that anisotropy has large influences on the kinetics (phases) and the dynamics (amplitudes) of seismic waves. We conclude that the anisotropy must be considered when processing seismic data.