The Value of Frequent Spot Seismic: 4 Years of Monitoring on the Weyburn Field

Summary In 2024, 4D imaging and spot seismic has been performed over the Weyburn field, in Saskatchewan, Canada, to monitor CO2 injection for Enhanced Oil Recovery (EOR). Between 2022 and 2024, three spot seismic monitoring campaigns were conducted and successfully detected CO2 plume. Each campaign consisted in the imaging of 16 spots, initially placed based on flow model predictions with the aim of tracking injection dynamics and potential mismatches between predicted and actual CO2 fronts. Whitecap Resources conducted in November 2024 a 4D seismic survey, which was successfully compared with spot seismic results, showing a promising complementarity of each technology. With sufficient repeatable data and a basic processing sequence spot seismic allows to perform time lapse detection. The first two spot seismic acquisitions occurred in 2022. Most spots within the CO2 plume extension prediction detected CO2, except one model mismatch at a spot where CO2 was detected outside of the predicted CO2 plume. On the second acquisition, the mismatched persisted and is today located into a high CO2 concentration area on the 4D amplitude changes map.