Abstract：I analyse seismic wave propagation in directionally fractured medium and the anisotropy. Wave propagation in directionally fractured medium was often modeled by using anisotropic wave equation and Hudson's way to solve for equivalent elastic parameters in fractured medium. The old method can hardly be used because it needs a great deal of computer's internal storage and very speedy operation. I put forward a new method. The new method consists of two steps:l)to insert fractures in uniform medium by using the flexibility of finite element gridding and knot splitting instead of solving for anisotropic equation.and 2)to model seismic wave propagation in fractured medium by solving isotropic wave equation. Consequently, anisotropy problem in fractured medium can be studied by using conventional isotropic finite element modeling. Numerical modeling results prove the method feasible.
