Petrophysical evaluation of clastic Upper Safa Member using well logging and core data in the Obaiyed field in the Western Desert of Egypt

Upper Safa Member is part of Jurassic Khatatba Formation; it consists of low net gross ratio sand streaks. The core and well logging data were used to perform a comprehensive reservoir evaluation. The Schlumberger application “Techlog” was used to perform the required evaluation analysis. Four oriented wells were selected for this study. The volume of shale “Vsh” using gamma-ray (GR) was used to evaluate the lithology and to discriminate sand “reservoir” from shale “non-reservoir”. A porosity model using the density log was constructed and used as an input to calculate Archie’s water saturation “Sw”. Porosity- Permeability (Poro-Perm) Transform was used to evaluate the reservoir permeability. The net reservoir and net pay thicknesses were seen attractive in three out of four wells. The reservoir quality parameters “Porosity and Permeability” were different from well to well. The hydrocarbon saturation “Sh” was high in the three wells. The hydrocarbon intervals depths were highlighted and considered in the perforation strategy.