Factors controlling production in hydraulically fractured low permeability oil reservoirs

Fundamentals of fluid flow in ultra-low permeability reservoirs need to be examined to understand production behaviours. In this paper, we perform sensitivity studies of reservoir properties (matrix permeability, heterogeneity, rock compressibility and reservoir pressure), fluid properties (bubble point pressure and initial dissolved gas oil ratio), rock fluid properties (relative permeabilities), completion parameters (fracture spacing) and operating parameters (bottom hole pressure) on production performances. Matrix permeability, rock compressibility, fluid properties and fracture spacing have major impact on oil recovery and gas oil ratio (GOR). More oil is recovered from higher permeability reservoir in the expense of higher GOR. Recovery increases with increasing rock compressibility since the pressure decline is more gradual in higher compressibility rocks. Oil phase becomes less viscous and more mobile due to higher amount of dissolved gas. Higher initial GOR improves production of oil with higher...