Petrophysical characterization and formation evaluation of sandstone reservoir: Case study from Shahd field, Western Desert, Egypt

Basem  CHIKIBAN; Mostafa H. KAMEL; Walid M. MABROUK; Ahmed METWALLY

doi:10.31577/congeo.2022.52.3.5

Basem CHIKIBAN Geophysics Department, Faculty of Science, Cairo University, Giza, Egypt
Mostafa H. KAMEL Geophysics Department, Faculty of Science, Cairo University, Giza, Egypt
Walid M. MABROUK Geophysics Department, Faculty of Science, Cairo University, Giza, Egypt
Ahmed METWALLY Geophysics Department, Faculty of Science, Cairo University, Giza, Egypt

DOI: https://doi.org/10.31577/congeo.2022.52.3.5

Keywords: Shahd SE field, formation evaluation, litho-saturation model, petrophysical interpretation workflow

Abstract

This paper aims to establish a complete workflow for a petrophysical evaluation to enhance and quantify hydrocarbon prospect and productivity of Shahd SE field, East Ras Qattara concession, Western desert, Egypt. The suggested workflow can, then, be used with the same steps and sequences for any petrophysical evaluation study. Well logs data from four wells were used for this study. The present data has drilled through three formations: (1) Bahariya Formation, which has been divided into two subzones; (I) Upper Bahariya, a shaly formation and (II) Lower Bahariya, the main reservoir present in our case study. (2) Kharita Formation, which consist of clean sand. We will evaluate the three most useful petrophysical parameters: (a) volume of shale (Vsh) using the gamma-ray (GR), (b) effective porosity Φeff) using the neutron log and the resulting volume of shale as an input, and (c) water saturation (Sw). Several equations were used to calculate the Sw. The best equation was Simandoux equation to put in consideration the shale model of the upper Bahariya. The results show that the net reservoir and net pay thicknesses were seen very promising in all four wells, all at the lower Bahariya Formation. The reservoir quality parameters "Effective Porosity (Φeff)" were almost the same for all four wells, as well as the high hydrocarbon saturation "Sh" for all four wells.