Aquifer Characterization and Modelling, a Case Study of Bahi Oil Field

Abstract

Natural influx of water in oil reservoir surrounded by water aquifers play a very important role in increasing oil recovery. The calculation of water influx is very difficult as it involves many uncertainty such as aquifer size, shape, and structure and aquifer rock properties. The main objective of this work is to detect the presence of aquifer as well as characterize the relative strengths of aquifers associated with Bahi oil field. In this study, Campbell and energy plots are used as diagnostic tools to identify the aquifer type based on the signature of production and pressure behavior. In model ranking, three models are investigated; Van Everdingen-Hurst unsteady-state model, Schilthuis steady-state model and Fetkovich pseudo steady-state model. The findings of this work showed that, the Van Everdingen and Hurst model is the best model to describe the Bahi aquifer with correlation coefficient of 98.64%. Further, results showed the water drive strength in the Bahi oil field is strong with edge aquifer size approximately twelve times the size of the reservoir and water encroachment angle is 278 degree.