BGES has developed a comprehensive and proprietary process to assess caprock integrity in thermal recovery projects including steam assisted gravity drainage (SAGD) and cyclic steam stimulation (CSS). These processes involve the injection of steam into the reservoir at high pressure and high temperature in order to mobilize the bitumen. Rock layers above, known as the caprocks, must display sufficient hydraulic and mechanical integrity to withstand injection pressures in an in-situ production. However, continuous or cyclic injections can lead to changes that alter in-situ stress states, reduce rock strength, initiates or re-open fractures, etc. Inability of the caprock to contain the steam and hydrocarbons may allow them to escape to shallower units and even the surface.
To mitigate risks of caprock failure, we use the following suite of assessments, based on geomechanics principles, to gain an in-depth understanding of possible failure mechanisms and to predict potential effects of thermal production on the in-situ conditions.