Abstract：Common-used the foil elastic wave equation-to carry out the numerical modeling of elastic wavefield only obtained a hybrid wavefield of P-wave and S-wave.When you want to obtain P-wave and S-wave wavefield,generally the wavefield separation is carried out after hybrid wavefield being obtained or using acoustic equation to model the P-wave and S-wave wavefield,but these methods are very difficult to ensure the amplitude of P-wave and S-wave do not disorder.The paper gave an equivalent equation of full elastic wave equation, which contains variations of both the hybrid wavefield and the pure P-wave and S-wave wevefield. Using pseudo-spectrum method to solve the wave equation,obtained totally separated wavefield of pure P-wave and S-wave while obtaining hybrid wavefield,and preserved the information of mutual transformation of P-wave and S-wave energy.The analysis of modeling wavefield showed using nu-merical modeling of elastic wave separation has lmportant meaning in respect of knowing the propagating rule of elastic wave.
