Estimation of Formation Pressure by using a New approach Along with Other Techniques in Two Selected Wells in Rumaila and Zubair fields

Abstract

Many studies indicated that the abnormal pore pressure (overpressure) could be a dilemma when drilling wells due to the severe effects might occur that raise the cost to ununbelievable rates. If overpressure happened, this could lead to several problems for instance kick, blowout and also to a geological disaster such as volcano eruption through the drilling, therefore the anticipation of this pressure is vital to prevent drilling problems.
The objective of this study is the real-time predication of pore pressure of two selected oil producing wells in Rumaila and Zubair fields in south Iraq region. Various approaches are used for this purpose such as the modified specific energy along with Rabia's formula of specific energy as well as from well logs. The calculated pore pressures are compared with the actual formation pressure obtained from Real Formation Test (RFT) and Measurements While Drilling (MWD) logs. The statistical comparison according the Mean Absolute Error (MAE) showed that the new suggested formula of pore pressure determination is the best among the other techniques being used in the present study leading to the possibility to apply the new technique on other wells in the same area and might on other regions.