The PRESSIM software models pressure generation and dissipation on a geologic time scale (Borge 2002, Lothe 2004). The software tool is developed at SINTEF Petroleum since 1997 and used for pressure quantification in many different geological basins and settings around the world.
PRESSIM quantifies the fluid flow and resulting pressure dissipation using a unique model for lateral cross-fault fluid flow (Borge 2000) and Darcy flow equations in the vertical direction. A Kozeny-Carman equation is used to relate permeability from the shale porosities provided by the empirical compaction models describing the compacting shales.
When the operation provides new pressure real-time data, the pressure ahead of the bit can be updated, based on the PRESSIM Monte Carlo results with a best case, minimum and maximum pressure prognosis. With new data input, the uncertainty will be narrowed
It is also important to have a tight link to the mudweight analysis/modelling, since they use pressure prognosis as an important part of the needed input.