Although papers comparing some standard functions with saturation models have been published, no consistent review exists comparing the performance of most of the universal saturation-height function quantitatively. The universal SHF is fast and straightforward, but robust enough to account for limited data and while another full data acquisition and advanced analysis are in progress (partially obtained). The method can help the subsurface team in understanding the water saturation nature in quick turnaround time before the completion of ongoing volumetrics estimation. Two best practices of this workflow are rapid and robust.

The paper reviews three of the universal saturation-height methods, namely those proposed by Choo, Kyi-Ramli, and K-Function. The comparisons between modelled and measured capillary pressure measurements over the most common functions and through different reservoirs are discussed. The advantages and drawbacks of each method are highlighted. Each technique is compared by investigating how accurately they model the saturation-height profiles of several wells from Offshore Malaysia. The work was carried out to independently assess which equations should be tested first during saturation-height studies. The differences for each capillary pressure between the water saturations estimated using the equations and those measured on the samples are examined in both graphic and quantitative terms.

The results of this study show that Choo (2010) model is one of the better performing saturation-height functions. However, the best results are achieved using this function, but this method is also the most challenging to execute in petrophysical and static modelling software. Of the conventional equation-based approaches, the K-Function model appears to have the most utility and are recommended as first choice saturation-height models to test. It only has two inputs for the modelling comprising of RQI and HAFWL.

This study continues the extended concepts of Adams (2016) and Harrison (2001) to describe quantitative comparisons between modelled and measured capillary pressure measurements over the functions and through different reservoirs.

The review presented could not include all possible equations, but shows which of the most frequently cited functions, is likely to be of utility. Areas for future improvement are also highlighted.

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