PRESSURE BUILDUP TEST ANALYSIS PROCEDURE OF A VERTICAL WELL COMPLETED WITHIN A PAIR OF INCLINED SEALING FAULT

ABSTRACT

This research presents the result gotten from a mathematical model for obtaining the angle of inclination of a fault in the reservoir using pressure buildup procedure. Pressure buildup test analysis has been used to investigate near wellbore environment, estimate reservoir pressure and reveal external reservoir boundary type. However, in spite of these benefits no consideration has been given for the angle of inclination of the fault or boundaries within which the well is completed. The angle of inclination of the boundaries of a reservoir has a significant impact on the pressure behavior of a well, and its performance. Knowledge of the inclination angle of the faults assist in well placement for optimum production. The objective of this research therefore, is to develop a procedure for calculating the angle of a well completed within a pair of inclined sealing fault using pressure buildup test data which is important for optimum reservoir performance. The buildup test procedure developed shows linear partial variation of Horner ratio at early shut in time and late shut in time, assuming constant rate of production before shut in. The coefficient of the early time Horner's ratio is the early slope. The late time Horner's ratio has coefficient which is the product of the early time slope and the number of images formed due to sealing fault angle. Finally, the procedure does not depend on image distances of the images from the object well. The result shows that that the model is only valid for long shut in time and the second slope must be gotten at the late time region for better accuracy.