Computer modeling of heavy oil reservoirs has become progressively more challenging in order to represent geological reality and its impact on fluid flow. A method has been developed in which completion, production, and injection information, coupled with the static well data, are used to model enhanced permeability channels that have been created around the wells as a result of production and/or injection.
Court heavy oil field located in West Central Saskatchewan, Canada is a Bakken heavy oil reservoir (17°API, in-situ viscosity of ~155 c.p). The field, which has been under an active waterflood depletion strategy for the last 20 years, has achieved a recovery factor to date of ~ 24%. The geological complexities found in the Bakken Formation at Court introduce many challenges for history matching. It was discovered that successful history matching required the introduction of enhanced permeability modifications (EPMs). The EPM regions were superimposed over the geological model. Flow simulations using the EPMs region concept resulted in a significant improvement in the overall quality of the history match at both the group and field levels. Sensitivity studies were also undertaken to determine the minimum EPM requirement to gain the history match.
This paper describes how to use completion, production and injection data in the flow model to predict the high permeability zones in the vicinity of a wellbore. As it will be discussed in more detail, this technique allows for the achievement of a reasonable history match using a Black Oil reservoir simulator. The model was history matched to liquid rate, water cut, and pressure. The simulation model has been used to evaluate the current waterflood and predict the possible future enhanced oil recovery (EOR) opportunities for this field.