Abstract:Wave-equation finite-difference algorithm can more preciously simulate seismic wavefield for any non-uniform medium,but have the issue of numeric dispersion. In a seismic wave forward simulation in titled transversely isotropic medium (TTI medium) with titled symmetric axis, in order to solve the issue of numeric dispersion of ordinary finite-difference operator, the paper constructed the weighted mean finite-difference operator of qP-wave equation in frequency-space domain,computed normalized phase velocity and determined the optimal weighted coefficient of weighted mean difference operator according to Gauss-Newton approach of optimization theory. Using ordinary difference operator and weighted mean difference operator to analyze the dispersion of normalized phase velocity and carry out numeric finite-difference simulation of qP-wave seismic wavefield in u-niform TTI medium (including isotropic medium and ellipsoid anisotropic medium). The simulated results showed that the weighted mean finite-difference operator is characterized by higher numeric precision and capable to effectively suppress the numeric dispersion by ordinary finite-difference operator,laying the foundation of qP-wave forward simulation of TTI medium in frequency-space domain.