Pembina Cardium CO2 Monitoring Project, Alberta, Canada: Timelapse seismic analysis—Lessons learned

Abstract The Penn West enhanced oil recovery pilot project is located in the Pembina Oil Field in west-central Alberta, Canada, with CO 2 injection into the 20 m thick Cretaceous Cardium Formation at a depth of 1650 m below surface. Time-lapse processing of the surface seismic monitoring data collected between March 2005 and March 2007 yielded no significant changes in P-wave seismic amplitudes or traveltimes between monitor and baseline surveys after ∼40,000 t of CO 2 had been injected. A small amplitude change in the Cardium Formation and deeper events were detected by a fixed geophone array in an observation well. We conclude that partial or full saturation of the reservoir pore space was restricted to the most permeable sandstone members of the Cardium Formation. The seismic data indicates that no leakage of CO 2 has occurred into shallow aquifers.