Joint inversion of laboratory-measured acoustic phase velocity and quality factor data

Abstract

The paper presents a new rock-physical model to describe the pressure dependences of the phase velocity and quality factor (Q). Acoustic laboratory data for P-wave velocity and Q factor were measured on the sandstone sample at 40 different pressures. The spectral ratio method was used to measure the Q factor data utilizing an aluminum sample (with the size and geometry of the rock sample) as a reference. The measured velocity and Q factor data were processed in an inversion procedure. The results showed that both the velocity-pressure and the Q factor pressure dependence can be well-described utilizing the newly developed rock-physical model in forward modeling. From the estimated inversion parameters, v_p and Q can be calculated for the full pressure range.