Enhancing Reservoir Delineation in the Ptah Oil Field, Shushan Basin, North Western Desert, Egypt: An Integrated Seismic-Petrophysical Approach

The PTAH oil field is located in Egypt's North Western Desert, near northwest fringe of the Shushan basin. the purpose of this study is to examine oil's potential in the area. The primary oil-bearing reservoirs in this region are Lower Cretaceous Alam El Bueib Formation (AEB-3D) unit and the Paleozoic Shiffah Formation (Shiffah B SD). This was accomplished by the analysis of seismic lines to determine subsurface structural features. The structural maps depicted broad NW-SE and E-W normal fault systems that created graben-horst formations which were created to depict the area's structural framework and provide important structural traps. The (AEB-3D) and Shiffah reservoirs are composed of fine-to coarse-grained that were deposited in a fluvial channel environment. Rare amounts of feldspars, lithic fragments, and clays are present in these sandstones, according to the petrographic analysis for core. The quartz percent is greater than 95% by volume and therefore all samples are Quartz Arenites. The petrographic analysis shows that the mineral composition has an effect on reservoir quality. The Petrophysical evaluation for AEB-3D indicates that the net pay thicknesses varying from (13–52 ft), effective porosity between (7.8–12.02%), shale content between (3.5–25%) and hydrocarbon saturation varying between 75.3% at Ptah-4X to 61.68%. For Shiffah B SD the net pay thicknesses varying from 129 ft at Ptah-1X well to 28 ft in Ptah-15, the effective porosity ranges from (7–10.61%) the shale content ranges from (3.8–13%) and hydrocarbon saturation varying between 84.2% at Ptah-1X to 52% at Ptah-4X. The hydrocabon saturation increases in the northwest direction, according to all petrophysical parameter data, which are displayed laterally in various isoparametric maps and vertically as litho-saturation cross-plots. Finally the integration between seismic and petrophysical data helps us to reduce the exploration risk and supports development plane across the study area. Based on this study several locations were proposed for exploration and development planes.