Prediction of critical oil rate for bottom water coning in anisotropic and homogeneous formations

Water or gas coning can adversely affect oil production in oil reservoirs. In oil reservoirs, a large oil rate can cause upward coning of water or downward coning of gas into the well perforations. Once gas or water is produced, the oil rate decreases and the cost of water and/or gas handling is increased. There is a critical rate below which the cone remains stable and does not break through to the wellbore. In the present work, a simple-to-use approach, which is easier than existing approaches, less complicated with fewer calculations, is formulated to arrive at an appropriate estimation of critical oil rate for bottom water coning in anisotropic and homogeneous formations with the well completed from the top of the formation. This simple-to-use correlation can be of immense practical value for petroleum engineers to have a quick check on estimating the critical oil rate for wide range of conditions without the necessity of any field test trials. In particular, petroleum engineers would find the proposed approach to be user friendly involving transparent calculations with no complex expressions for their calculations.

► Estimation of critical oil rate for bottom water coning in anisotropic and homogeneous reservoirs. ► Development of a simple-to-use mathematical predictive tool. ► Presenting a case study for the benefit of engineers to demonstrate clearly the usefulness of proposed tool.