A 3C-4D surface seismic and VSP program for a coalbed methane and CO2 sequestration pilot, Red Deer, Alberta

Donald C. Lawton, Gary F. Margrave, Sarah Elizabeth Richardson, Robert R. Stewart

CREWES is embarking on a three-year program to develop and conduct a repeated seismic monitoring experiment at a site in Alberta that is proposed for coalbed methane (CBM) production, stimulated by CO2 injection. The main objective is a proof-of-concept test for seismic-imaging technology to successfully monitor the motion of the subsurface gas plumes and assess whether time-lapse seismology can verify that the injected gases are truly sequestered. Secondary objectives are to test seismic imaging technology to monitor water withdrawal from the coal zone prior to CO2 injection and methane production. The site is near Red Deer, Alberta, where coals of the Ardley Zone of the Lower Tertiary-Upper Cretaceous Scollard Formation are up to 8 m thick at a depth of approximately 290 m below surface. Based on numerical modelling, a surface seismic has been designed with a 400 m x 400 m patch, orthogonal source and receiver lines 40 m apart, with shot and receiver intervals of 10 m. A vertical seismic profile survey has also been designed, with 50 m source offsets to a maximum offset of 250 m.