RESUMO
Baltim Eastern and Northern gas fields in the offshore Nile Delta have very high gas condensate accumulations. Therefore, the present research evaluates Abu Madi and Qawasim Formations and defines the petrophysical parameters for them using various data from five wells composed of wireline logs (gamma-ray, density, neutron, sonic, resistivity), core data, pressure data, and cross-plots. In the current study, the formations of the main reservoirs were evaluated qualitatively and quantitatively based on the petrophysical analysis to assess the production potential. Based on the lithological identification, the two main reservoirs (Abu Madi and Qawasim Formations) are composed of sandstone, calcareous shale, and siltstone. The main petrophysical parameters (Shale volume, effective porosity, net thickness, and fluid saturations) were mapped to track the areal petrophysical variations in the field. The results of the petrophysical analysis reveal that the main reservoirs are promising for the hydrocarbon potential with effective porosity of 18%, low shale content with an average value of about 21%, higher gas saturation of average value of nearly 58%, net reservoir thickness ranges from 25.5 to 131.5 m, net pay thickness (effective thickness) ranges from 6 to 61 m. Also, the conventional core analysis affirms that the main reservoirs are of good effective porosity with high horizontal and vertical permeability values. There is a good match between the well-log results and the pressure data with the production data (DST "perforation tests"). Baltim East (BE3) well has the most desired petrophysical characteristics in the Baltim East gas field, while, the Baltim North-1 (BN1) well showed the most favorable petrophysical parameters in the Baltim North gas field. Different fluid contacts (gas water contact GWC) were detected by integrating all reservoir pressures. The integration of different data in our present work (well logs, core measurements, and pressure data) could reduce the drilling risks and help to determine the best locations for future exploration and development, which is considered a big challenge in the petroleum industry.
RESUMO
Middle Jurassic reservoirs present challenges in the northern segment of the Western Desert due to geometric uncertainties arising from structural configurations, lateral facies variations, diverse lithologies, and heterogeneous reservoir quality. Consequently, this study employed an intricate approach, constructing detailed 3D geostatic models by amalgamating diverse datasets, including 2D seismic sections and digital well-logs. The focus of these 3D models was on the Khatatba Formation (Upper-Safa Member, Kabrit Member, and Lower-Safa Member) in Matruh-Shushan Basin in the North Western Desert. The objectives encompassed assessing hydrocarbon potential, precisely estimating reserves, formulating development and exploration strategies, and identifying prospective drilling locations. The resultant structural model revealed a compartmentalized region marked by major and minor NE-SW trending normal faults, establishing structurally advantageous locations for hydrocarbon trapping within the study area. Petrophysical analyses highlighted the promising potential of the Upper-Safa Member as a reservoir, featuring porosity values ranging from 10 to 18%, peaking in the northeast sector, volume of shale (Vsh) between 15 and 24%, water saturation (Sw) spanning from 18 to 53%, and increased sand thickness towards the eastern section. Similarly, the Lower-Safa Member demonstrated favorable reservoir attributes, including porosity values ranging from 10 to 16%, with higher values in the southeastern part, Vsh between 17 and 28%, and Sw varying from 15 to 47%. The study findings underscored the hydrocarbon potential in the northeast block of the study area for the Middle Jurassic Khatatba Formation. These insights contribute valuable information for decision-making in exploration and production endeavors within the basin.
