Acoustic impedance inversion of vintage seismic data over a proposed CO₂ sequestration site in the Lake Wabamun Area, Alberta

Abdullah A. Alshuhail, Donald C. Lawton, J. Helen Isaac

Seismic inversion of the Nisku Formation in the Lake Wabamun area has revealed contrasts in acoustic impedance caused by lateral changes in lithology and/or porosity of the Nisku Formation. This interpretation is constrained by well control and supported by seismic modelling, which suggests that changes in Nisku thickness over the range encountered in the study area has only a small effect on acoustic impedance. Thus, acoustic impedance mapping may provide one approach in pursuing favourable sites for CO₂ injection in addition to the conventional time structure, amplitude maps and other seismic attributes. Our analysis revealed favourable low-impedance, high-porosity locations that could be potential injection sites.