关键词: ATI介质, 群速度, 相速度, 方位变化

Abstract: Based on the analytic solution of body-wave velocities and polarizations for arbitrary spatial orientation TI media (ATI), the characteristics of body-wave velocities with azimuth variation in ATI media can be obtained by using simulating calculation. The result shows that the body-wave propagation in ATI media is related to not only the five elastic constants of TI media, but also the dip angle of the symmetrical axis of TI and the azimuth between the symmetrical axis of TI and the survey line. That is, the spatial orientation of TI symmetry axis and surveying line azimuth have an effect on body-wave velocities. The patterns of body-wave group-velocities and phase-velocities are fixed relative to TI symmetry axis and exhibit certain symmetry and repetition of azimuth variation. For complex structural geology of ATI areas, this research can provide the patterns of body-wave group-velocities and phase-velocities to benefit the theoretical research. The result can also be used directly to analyze VSP and cross-well seismic data.

Key words: ATI media, Group-velocity, Phase-velocity, Azimuth variation