Impact of Interlayer Distribution on SAGD Performance and Countermeasures in Oil Sands Project

The interlayer tends to reduce vertical permeability of reservoir and interfere with steam and heated oil flow. This issue becomes the key factor impacting SAGD performance of oil sands. The core data of Mackay River oil sands demonstrates that interlayers are distributed with different thickness, extended range, and distribution frequency in the reservoir; the impact of these properties on SAGD performance and steam chamber growth as well as countermeasures remains to be further studied. Four types of SAGD well pairs were divided according to the location and distribution frequency of interlayers. Based on two-dimensional (2D) physical and three-dimensional (3D) numerical simulation, the effect of interlayer location on SAGD performance and steam chamber growth was discussed. On this basis, the feasibility of combining single-well SAGD (SW-SAGD) technology with dual horizontal SAGD wells for type C was evaluated by 2D physical simulation. In addition, the strategy of well pair placement, SAGD well pair with dual-tubing strings, and smart well technology combined with intelligent steam injection strategy was discussed with 3D numerical simulation.