Reservoir characterization and geologic modeling of the Lower Cretaceous Muddy Formation at Bell Creek Field, Montana, USA

Abstract

The Lower Cretaceous Muddy Formation at the Bell Creek Field, Montana, USA, is characterized by a clastic sequence of mixed lithofacies. An integrated workflow was applied to define the reservoir compartments and distribution of petrophysical properties throughout the central and northern areas of the field. The workflow focused on the heterogeneity of the reservoir flow units, diagenetic complexities, and the associated compartments. The compartments play a considerable role in controlling the connectivity and fluid flow through the reservoir. Descriptions of the reservoir properties were used as inputs to a three-dimensional (3-D) geologic model for history matching and prediction of CO2 flooding. History matching of the primary production of the Muddy Formation helped to improve understanding of the distribution of the rock and fluid properties. The simulation model was then used to forecast future CO2 flooding in the study area. Following CO2 injection, the collected production data were utilized to verify the validity of the model by comparing the production forecast with the actual field results. The simulation model successfully predicted the CO2 flood response, pressure, and production data.