Establishing the Formation Pressure Profile of Predrill Well Based on Adjacent Wells Data

The formation pressure plays a very important role in drilling engineering. So it is of great significance to predict formation pressure before drilling. In order to solve the problem, the concept of formation matrix and wellbore matrixwere put forward. Also the method of epitaxial transplantation for the regional formation pressurewas proposed. With the concept of wellbore pressure matrix, the target wellbore pressure matrix can be builtby dealing with the adjacent wellborepressureusing the method of depth adjustment and weighted distance correction. Finally, we can obtain the formation pressure of the targetwell. Case study of Qinghai Oilfield was carried out to test the method. Through comparative analysis, the maximum relative error of the transplantation pressure and logging interpretation pressure is 4.2%. The result indicated that the accuracy and reliability of the method can meet the engineering requirement. This is conductive to designers to predict formation pressure which can provide the basis for the casing design and the selection of the drilling fluid density.