Rock Physics Diagnostics of the Unayzah Sandstone

The Unayzah sandstone in Central Saudi Arabia is a mature consolidated formation. The effective medium model of Raymer-Hunt-Gardner accurately predicts the effects of porosity, lithology and pore-fluid on the seismic response. Empirical results are calibrated to measured data at well log and seismic scale to confirm the validity of the model. This model-driven approach will be used to constrain the amplitude-versus-angle (AVA) inversion results for P-impedance and Vp/Vs ratio, which is then used to predict porous oil-saturated zones within the formation.