Impact of Varying Saturation Height Function Methods: Examples from Different Fields
Uncertainties in saturation height modelling manifest themselves in the volume of hydrocarbon being calculated and the representation of the transition zone within the reservoir. Ideally, all the available data should be used to calculate, corroborate and QC saturation height functions. It is important to investigate multiple scenarios and differing approaches to derive saturation height functions and test the effect of each approach on the reservoir.
The goal of this study is to highlight the value of considering multiple approaches and differing scenarios when saturation height modelling; even if it means using multiple functions for different fault blocks and/or porosity/permeability class. As this study shows, the volume of hydrocarbon calculated can vary significantly between saturation height methods used. In particular, the impact of porosity changes on saturation height functions should be investigated. As should whether using a function derived from well logs or a function derived from upscaled logs is appropriate for a given reservoir model.