Pore pressure prediction models are an integral part of the well planning procedure and as such, must be accurately built. Industry standard methods include analysis of wireline log data from offset wells and implementing techniques such as, Equivalent Depth and Eaton Ratio methods, to understand the shale pressures. These shale-based pore pressure prediction methods, although robust, can become uncertain at high temperatures due thermal effects in the shales and thus leading to an under prediction of the actual overpressure and potentially an incorrect well design. To help reduce the uncertainty at high temperatures we present a pore pressure prediction model based on vertical effective stress, to describe the loading (mechanical compaction) and unloading (fluid expansion and chemical compaction) behavior of shales.
|Publication status||Published - 16 Jun 2014|