Porosity and Permeability Prediction through Forward StratigraphicSimulations Using GPM TM and Petrel TM : Application in ShallowMarine Depositional Settings

Abstract. The forward stratigraphic simulation approach is used in this work to predict porosity and permeability attributes in the Volve field, Norway. This was achieved by using spatial data from the forward stratigraphic model to control the distribution of porosity and permeability. Building a subsurface property model that fits data at different locations in a hydrocarbon reservoir is a task associated with high levels of uncertainty. An appropriate means to minimise property representation uncertainties is to use geologically realistic sediment distribution and or stratigraphic patterns to predict lithofacies units as well as petrophysical properties. The workflow used are in three parts; first, the geological process modeling (GPMTM) software developed by Schlumberger was used to simulate scenarios of sediment deposition in the model area. Secondly, an estimation of lithofacies proportions in the stratigraphic model was done using the property calculator tool in the PetrelTM software. Finally, porosity and permeability values are assigned to corresponding lithofacies-associations in the forward model to produce a forward stratigraphic-based petrophysical model. Results show a lithofacies distribution that is strongly controlled by sediment diffusion rate, sea level variation, flow rate, wave processes, and tectonic events. This observation is consistent with real-world events were sea level changes, volume of sediment input, and accommodation space control the kind of stratigraphic sequence formed. Validation wells prefixed VP1 and VP2 in the original Volve field petrophysical model and the forward stratigraphic-based models show a good match in porosity and permeability attributes at 5 m vertical sample intervals. By reducing the level of property uncertainty between wells through forward stratigraphic modeling, an improved porosity and permeability can be achieved for an efficient field development strategy.