Monitoring Health of Minagish Reservoir Through Tracking Movement of Reservoir Fluids

Abstract

This paper describes the methodology adopted to Monitor Health of Reservoir by tracking historical movement of reservoir fluids in an Oolitic limestone reservoir in Kuwait. The reservoir has a weak aquifer support, hence Gas injection followed by Water injection was implemented to provide necessary pressure support and improve overall reservoir sweep. Since injection is being undertaken for a long period of time, drainage radius of water injectors is estimated through streamlines and accordingly the reservoir is divided into different regions based on the injection radius. Thereafter, historical movement of reservoir fluids in each region is analyzed for a period of 60 years to understand the following, Identify the position of leading edge of water and its associated flood-front with respect to each zone & region.Capture oil saturation changes during the last 60 years and identified which regions had minimal changes in oil saturation to accelerate implantation of new infill wells to maximize recovery.Locate where is the remaining oil in the reservoir and identified on what is it causing presence of remaining oil at any given location.Capture the changes in region-wise pressure by coupling with movement of Injected water.Generate distribution of Voidage replacement ratio and injection efficiency in different regions of the reservoir.