Abstract：The issue of elastic wave transmission in ani-sotropic fluid-filled pore medium is one of difficulties in current petroleum exploration and study of seismology. Based on Biot theory, the paper presented staggering grid finite-difference algorithm with any even-order precision of 3-C elastic wave e-quation in 2-D biphase dip anisotropic medium,and conducted simulation of elastic wavefield in homogeneous and two-layered biphase VTI and TTI media. The snapshots of wavefields and synthetic seismograms showed that under the conditions of the certain angle between the polarization direction of S-wave source and the symmetric axis of TI medium with smaller scattering coefficient, there exist fast S-wave, slow S-wave, fast P-wave and slow P-wave in solid and fluid phases; the phenomenon of S-wave splitting and acute angle and triple-branch of wave front in biphase TI medium are basically similar to that in TI medium. The only difference is that the velocity of elastic wave become slower with the characters of dispersion and attenuation in viscid phase; the wave pattern is character of reflection when the reflecting wave is transformed from the direct wave.
