Integration of Continuous Time Lapse Seismic Data into Reservoir Models Using Onset Times

A permanent buried seismic monitoring system was deployed at Pad 31 in the Peace River Unit (Alberta, Canada) to understand the reservoir sweep during steam injection in the heavy oil field. Over 500 daily time lapse seismic surveys of the reservoir state (in terms of two-way travel time) are available throughout the monitoring period to study the changes propagation in the reservoir. We propose an efficient approach to integrate such frequent time lapse seismic data into reservoir models based on seismic onset times, the calendar time when the seismic attribute crosses a pre-specified threshold value at a given location. We demonstrate the power and utility of the proposed approach using time lapse data from a Cyclic Steam Stimulation (CSS) cycle in the pad with a total of 175 seismic surveys. The study shows the effectiveness of the method to handle large number of surveys by compressing them into a single map of onset times which clearly displays the changes propagation. Furthermore, the onset times can be used to efficiently update reservoir models through history matching of the time-lapse seismic data.