College of Geo- exploration Science and Technology，Jilin University，Changchun 130026，China

Based on first order velocity- stress wave equation，and using the Fourier transform，in which spa- tial derivatives are computed by multiplication in the frequency domain，the authors simulate the wave field of the medium． Combining with geological problems probably existed in practical exploration，the authors designed many geological models，such as the anticline- ，syncline- ，lens- ，and fault- intrusion models，and realized pseudo- spec- trum forward modeling， made synthetic seismogram and analyzed the characteristics of wave field dynamics． The re- sults show that the pseudo- spectral method has high accuracy and reliability． It can be directly used to assist in the assistance of seismic field work design，and the inversion and data interpretation．