The Nelson full field model: using iterative quantitative improvements from the initial framework to the final history match

The Nelson Field is a stratigraphically complex, channelized reservoir that has been in production since 1994 and is at the mid-mature stage of field life. The current management strategy is focused on identifying infill well locations with the aim of recovering bypassed oil. A key component to identification of such target locations is an accurate reservoir model to highlight unswept areas through simulation. To date, a number of generations of reservoir models have failed to history match. The causes of failure are poorly understood. Recent insights into both the static and dynamic behaviour of the field have led to the building of a new model in an attempt to understand the production performance. There are three key areas of change in the new static model: a new structural framework; a new macrofacies model; and the subdivision of petrophysical properties associated with that model. The model was improved iteratively using data from two discrete sources: seismic close-the-loop and dynamic history matches. The full field model has helped to evaluate a number of possible infill targets and has been used to aid in well and reservoir management to better manage the field performance.