The seismic forward modeling using Born approximation equation based on rheological body

The conventional τ method assumes that the stress relaxation time is approximately equal to the strain delay time, leading to the constant Q model with low precision. In this study, an improved τ method is proposed by an accurate equation of Q value based on generalized rheological body so as to solve the parameters of constant Q model. According to the seismic wave scattering theory, the first-order Born approximation equation in viscoacoustic media is derived based on generalized rheological body and then the first-order Born approximation of stress-velocity equation is obtained for the viscoacoustic media with convolutional perfect matched layer (CPML) boundary. The wave fields and records are compared through numerical simulation by full wave equation, first-order Born approximation equation and one-way wave equation. And it is also discussed that the precision of travel time and amplitude of the seismic wave obtained by the viscoacoustic first-order Born approximation equation with velocity perturbation and Q perturbation.