Developing Generalised Capillary Pressure Curves and Saturation Height Function for Shuaiba Carbonate Reservoirs in Field A

Abstract

Abstract Shuaiba carbonate reservoirs have wide variations in their basic petrophysical properties (porosity, permeability) and hence capillary pressure. These properties require characterization since they have significant impact on hydrocarbon volumes estimations and production forecast. In addition, capillary pressure is one of the most important rock-fluid properties that petroleum engineers use to estimate initial oil distribution in the reservoir by converting it into Saturation Height Functions (SHF). However, generating representative capillary pressure curves is very challenging often due to limited data, large variation in rock fabrics and that capillary pressure measurements often have to be made with non reservoir fluids. Corey Brooks and Lambda functions were compared in the analysis and a SHF was derived from both core and log results. The high level of heterogeneity was shown in field A even using one set of porosity classes. A general SHF was obtained for field A and saturations from Log and core data can be matched to the SHF for field A Shuaiba reservoirs. A very good match was observed in the good quality reservoir sections. However there was no match in some wells at the water leg and poor quality reservoir sections. Introduction The main aim of this study was to see if it is possible to develop generalised capillary pressure (Pc) curves and avoid saturation height function (SHF) for the Shuaiba carbonate reservoir. First part is an introduction that includes a geological overview, statements of the problems plus objectives and unit system section in appendices. The second part presents a literature review of research related to this study. In third part, the study methodology is introduced. The results and analysis are discussed in 4th part. Last part states the conclusions and recommendations of this study.