Reliable SCAL Data for Reservoir Modeling: Case Study of a Niger Delta Reservoir

Abstract Special Core Analysis (SCAL) data has a direct impact on the way fluids are allocated and distributed in the reservoir and simulation models, which would directly impact reservoirs' STOIIP estimation and their distribution. Moreover, it directly affects the performance of secondary and EOR flooding processes, and in turn impacts the accuracy of the oil and gas reserve estimates, and the management of these reserves. Therefore, SCAL data could be considered as one of the most critical reservoir input data for reservoir simulation models. This paper shows how a reliable SCAL data was used for Reservoir Modeling workflow and it's impacts on the accuracy of the oil and gas reserve estimates results of integrated reservoir studies performed on XX reservoir of an onshore field in Niger Delta. The studies include petrophysical analysis, static reservoir models and building Numerical models. This Paper sheds light on the theoretical and experimental background of SCAL data. It explains the concept of reservoir wettability and different factors that could induce changes in reservoir wettability. Further, the concept of capillary pressure and its associated hysteresis for different wettability conditions were considered. The concepts of two phase water/oil and gas/oil relative permeability curves and how to generate three relative permeability data for water wet, mixed and oil wet reservoirs were demonstrated. It clarifies the saturation end point of both capillary pressure and relative curves as a function of reservoir heterogeneity and wettability, the idea of reservoir wettability profile.