Petrophysical and Gas Chromatographic Analysis Integration for Hydrocarbon Identifications in Cretaceous Reservoirs, Azhar Field, Beni Suef Basin, Egypt

Abstract

The petrophysical assessment of the Cretaceous succession from late Albian to Cenomanian (Upper Kharita, Bahariya formations, and Abu Roash ‘ G ’ Member) con fi rmed by gas chromatographic analysis utilizing well-log data and core data from the Azhar A-2 and Azhar E ¡ 1X wells located within the Beni Suef Basin, Western Desert of Egypt, was the aim of this work. The oil net pay zone of the Upper Bahariya Formation in the Azhar A-2 well is more effective and has a lower thickness than that of the Upper Bahariya Formation in the Azhar E ¡ 1X well. The gas chromatographic value analysis of the two wells (Azhar A-2 and Azhar E ¡ 1X) gives a good signature about the type of hydrocarbon content. The Abu Roash ‘ G ’ Member is characterized by the presence of oil in its lowermost part, and the C 1 /C 2 ratio also con fi rmed the presence of oil, which ranges from 3 to 7, where 40 greater than wetness ratio greater than 17.5, character ratio greater than or equal to 0.5 with balance ratio less than 17.5. In the upper part of A/R, ‘ G ’ Member is characterized by the presence of oil/heavy oil because the wetness ratio is greater than 40 and the character ratio is greater than or equal to 0.5 with the balance ratio less than 17.5 and the C 1 /C 2 ratio also con fi rmed the presence of oil/heavy oil that ranged from 2 to 5. The Upper Bahariya Formation is characterized by the presence of oil/heavy oil, where the wetness ratio is greater than 40, character ratio is greater than or equal to 0.5 with the balance ratio less than 17.5, and the C 1 /C 2 ratio also con fi rmed the presence of oil and heavy oil, which ranges from 2 to 7.7. The statistical analysis of the Upper Kharita Formation conventional core data indicated that the Upper Kharita Formation is characterized by fair-to-good porosity, fair permeability, and its gas chromatographic value analysis shows the presence of oil/heavy oil, where the wetness ratio greater than 40, character ratio greater than or equal to 0.5 with balance ratio less than 17.5, and C 1 /C 2 ratio also con fi rmed the presence of oil/heavy oil, which ranged from 1.5 to 7.