Frequency-domain 2D seismic forward modeling method based on the LSCG method and the wavenumber compensation

The seismic forward modeling technique is critical to seismic exploration.Moreover,it shows a faster rate and higher calculation efficiency in the frequency domain than in the time domain.Presently,there is a need to complete the forward calculation in the frequency domain efficiently and accurately.The specific problems include the numerical dispersion and the high memory consumption for calculating and decomposing impedance,which should be reduced by improving the calculation efficiency.Different from the conventional direct method,this study adopted the least-squares conjugate gradient (LSCG) method used to determine the impedance matrix for the frequency-domain forward modeling and proposed an expression for wavenumber compensation to suppress the numerical dispersion.The numerical tests of simple and complex models show that the LSCG method can effectively reduce the calculation time and that the frequency-domain forward modeling method based on wavenumber compensation can effectively suppress the numerical dispersion and thus improve the precision of wave field simulation.