Process Based Stochastic Modelling of Deep Marine Reservoirs

Deep marine deposits are an important reservoir type. While existing object and trend based stochastic modelling approaches can capture some of the heterogeneity, the limited quantities of data result in a very broad spread of possible model outcomes. Furthermore, such modelling approaches fail to honour the key factors that control the distribution of reservoir sand, namely accommodation, sediment supply and basin topography.<br><br>A new simplified process based modelling tool capable of rapidly recreating the flow and deposition of hundreds of flow events is presented. The model accounts for seabed topography, gravity, friction, kinematics, ocean currents, sedimentation and erosion rates. Individual events start in a confined feeder channel and experience a hydraulic jump where the flow stalls and widens into a lobe. This method is combined with stochastic elements for inclusion of reservoir uncertainty and conditioning to well data.<br><br>The geometry of a deep marine deposit is modelled by generating many individual events and stacking them on top of each other, thereby mimicking the actual sequence of deposition. Intermediate deposition of clay rich material, from hemipelagic material and numerous small clay rich mass failure events, are also modelled. The model has been successfully tested on a synthetic and real seabed data.<br>