Principal stress pore pressure prediction: utilizing drilling measurements to predict pore pressure

摘要

A novel method of predicting pore pressure has been invented. The methodutilizes currently recorded drilling measurements to predict the pore pressure of theformation through which the bit is drilling. The method applies Mohr?s Theory todescribe the stresses at the bottom of the borehole. From the stress state and knowledgeof Mohr?s Envelope, the pore pressure is predicted. To verify the method, a testprocedure was developed. The test procedure enabled systematic collection andprocessing of the drilling data to calculate the pore pressure prediction. The testprocedure was then applied to industry data that was recorded at the surface. Theindustry data were composed of wells from different geographical regions.Two conclusions were deduced from the research. First, Mohr?s Theory indicatesthat the model is valid. Second, because of too much variation in the torquemeasurements the model cannot be proved and requires further investigation.