A prestack simultaneous inversion method for sensitive elastic parameters of tight reservoir

Young's modulus and Poisson's ratio are the important elastic parameters representing the brittleness of tight reservoir rock, and Gassmann's fluid item is regarded commonly as a fluid factor in seismic fluid identification. Prestack seismic inversion is a feasible and effective way to obtain such parameter from prestack seismic data. For the tight reservoir prediction and fluid identification, a new prestack simultaneous inversion method for sensitive elastic parameters of tight reservoir is proposed. Based on the pore elastic reflection coefficient approximate equation, we derive a P-wave reflection parameter equation of Young's modulus, Poisson's ratio, Gassmann's fluid item and density. On this basis, a prestack simultaneous inversion method for sensitive elastic parameters of tight reservoir is constructed using the elastic impedance inversion technique based on Bayesian inversion framework. Model and actual data tests show that the newly proposed prestack simultaneous method can robustly obtain sensitive elastic parameters of tight reservoir from prestack seismic data, which offers a reliable technical approach for the tight reservoir prediction and fluid identification. ©, 2015, Science Press. All right reserved.