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.

By using the forward modeling theory of elastic wave field in directionally-fractured medium, we have ascertained absorbing boundary condition of anisotropic medium,and synthesized the surface-seismic and VSP data which result from same geologic model but reflect different fracture properties (or density).

The present paper describes the transmission process of elastic wave energy during the dynamic measurement in the cases of (1) varying impedance pile,(2)varying section pile and (3) varying impedance and section pile,viz.