Gradient Pore Pressure Modelling with Uncertain Well Data

Abnormal pore pressures can result in drilling problems such as borehole instability, stuck pipe, circulation loss, kicks, and blowouts. Gradient pore pressure prediction is of great importance for risk evaluation and for planning new wells in early stages of development and production of oil reservoirs. In this paper, a stochastic simulation with point distributions method is presented to integrate uncertain data in pore pressure cube characterization. The method consists in the use of direct sequential simulation with point distributions. Wells data, in this case, are considered “soft” data, of which uncertainty is quantified by local probability distribution functions or a set of values. A case study using a real dataset is also presented to illustrate the results.