Performance Evaluation of a Mature Miscible Gas Flood at Prudhoe Bay

Abstract

Abstract This paper summarizes the acquisition, conventional and compositional core analysis, and reservoir simulation history match of a core taken roughly 300 ft from a production well in the most mature area of the Prudhoe Bay Miscible Gas Project (PBMGP). Fine-gridded reservoir simulations yielded a good match of the offset well production rates and also of the observed compositional behavior of the core. The data showed that roughly 70% of the cumulative EOR came from reducing the residual oil saturation near the injection well. The remaining 30% was due to oil swelling. The swelling mechanism was especially important near the production well where the core was taken. Both simulation and field data show that additional miscible gas injection into this area would yield very little incremental EOR.