Numerical Modeling of Geomechanical Effects of Steam Injection in SAGD Heavy Oil Recovery

The Steam Assisted Gravity Drainage (SAGD) process is a thermal enhanced oil recovery (EOR) method that appears tremendously successful, especially for bitumen. SAGD process results in a complex interaction of geomechanics and multiphase flow in cohesionless porous media. In this process, continuous steam injection changes reservoir pore pressure and temperature, which can increase or decrease the effective stresses in the reservoir. Quantification of the state of deformation and stress in the reservoir is essential for the correct prediction of reservoir productivity, seal integrity, hydro fracturing, well failure and also for the interpretation of 4D seismic used to follow the development of the steam chamber. In SAGD process, the analysis of reservoir-geomechanics is concerned with the simultaneous study of fluid flow and mechanical response of the reservoir. Reservoir-geomechanics coupled simulation is still an important research topic. To perform this kind of simulation, a solution is to use a finite element based simulator to describe geomechanics and a finite volume based simulator to describe fluid flow. In this thesis, the SAGD coupled thermo-hydro-mechanical modelling is conducted using PumaFlow reservoir simulator and Abaqus as the geomechanical simulator. The main issues being investigated in this study were (1) the coupling strategy, (2) the geometry and (3) type of gridding system. This work was performed on synthetic cases.