Coupled Geomechanical-fluid Flow Impacts on Time-lapse Seismic for Waterflooding and Thermal Recoveries

4D seismic quantitative interpretation remains a challenging process because simultaneous changes in several dynamic properties can make the estimation of these properties ambiguous from 4D seismic. In this study, a coupled geomechanical-flow simulation has been utilized to investigate the individual and combined impact of fluid saturation, pressure, temperature and induced stress on compressional wave velocity in water flooding and thermal recoveries. The time-lapse response is modelled based on coupled geomechanical-flow simulation. The analysis reveals specific characteristics of thermally induced stress for an enhanced recovery such as steam injection in heavy oil. Our study suggests that thermal stress can be substantial during the steam injection and should be considered in addition to pressure induced stress in the reservoir. Injected steam significantly reduces the velocity due to low velocity nature of steam. On the other hand steam injection adds to total stress which will act like an additional load due to the expansion of the reservoir rock and resistance of overburden and side burdens. The examinations performed in this paper demonstrate the crucial need to do 4D seismic interpretation based on the coupled analysis of fluid flow and geomechanics.