EFFECTS OF RESERVOIR HETEROGENEITIES ON HEAVY OIL-RECOVERY BY STEAM-ASSISTED GRAVITY DRAINAGE

Previous studies of the SAGD process have been based on homogeneous reservoir models. In this paper, new experiments are described which simulate heterogeneous reservoirs. These include reservoirs with thin shale layers and reservoirs containing horizontal layers of different permeabilities. The results show that a short horizontal barrier does not affect the general performance greatly. A long horizontal barrier decreases the production rate but, in some configurations, not nearly as much as might be expected. It is observed that faster production is found when a higher permeability layer is above a lower permeability layer than when the conditions are reversed.