Petrophysical Properties and Oil Initially in Place (OIIP) of the Byda Formation, NC74 Concession, Sirte Basin, Libya

Abstract

The Byda Formation is one of the main reservoirs in the Sirte Basin, Libya. This study evaluates its petrophysical properties in the Al-Samah Field (NC74) using well-log data from three wells (F1, F2, and G1). Reservoir characterization included calculating shale volume (Vsh), effective porosity (Φ), permeability (K), water saturation (Sw), and oil saturation (So), followed by lithology interpretation and oil initially in place (OIIP) estimation using the volumetric method. The results indicate that the reservoir is predominantly limestone with moderate to good reservoir quality. The average effective porosity was about 12%, the average permeability was 577.73 mD, and the average oil saturation was approximately 50%. Well F1 exhibited the best reservoir quality. The estimated OIIP was 7.5 MMSTB. These findings provide valuable information for reservoir characterization, reserve estimation, and future field development.