An innovative way of computing reliable density from impedance inversion methods

Considering the importance of density for characterizing the conventional/unconventional plays, attempts have been made to compute it using vertical component seismic data as well as multicomponent seismic data for characterizing the Duvernay shale play in Alberta, Canada. Simultaneous inversion (PP) and PP-PS joint inversions were followed for density estimation as these are two conventional approaches considered usually for computing it from seismic data. Knowing the advantage of multicomponent data for deriving the different elastic parameters (Pimpedance, S-impedance, density, Young’s modulus, Poisson’s ratio, etc.), prestack joint inversion results were compared with the simultaneous inversion. Though a better-quality estimation of Pand S-impedance is noticed with prestack joint inversion, this method is not able to provide a reliable estimation of density from seismic data. The reason for the multicomponent seismic data falling short of reliable determination of density is explored in this study. Thereafter, a novel approach for estimating reliable density attribute from seismic data is also proposed.