Publications

Material balance is an oil reserve calculation method that works based on cumulative production. However, in some cases, this method has trouble accounting for a weak water drive, which could result in a significant material balance error. The Campbell Plot method, as an improvement for the analysis of material balance, can be used to evaluate the performances of water influx in reservoirs through analyzing the trend lines of the oil/gas decline production. This method uses the ideal cube model of a water drive reservoir and the transmissibility reduction in the reservoir simulation concept to analyze the performance of water influx (by running the sensitivity of water influx as well). The sensitivity is shown to explain the change in the trend line deflection in the Campbell Plot as an indication of water influx performance. In this study, the Campbell Plot was utilized to evaluate the performance of water influx and to find the correct value of the Original Oil In Place (OOIP) of the “Dale Amazone” field. To obtain the correct OOIP, we compared the Campbell Plots for the value of OOIP when the water influx effect was ignored with the Campbell Plot of the field when the water influx effect was analyzed.