Reservoir Characterization of The Bahariya Formation Using Core analysis and Well logging Integration at Al Zahraa Field, North Western Desert, Egypt

Document Type : Original Article


1 Exploration Department, PetroShahd Company, Egypt.

2 Geology Department, Faculty of Science, Al-Azhar University, Nasr City, Cairo, Egypt.


The Bahariya Formation encountered in Al Zahraa oil and gas field is subdivided informally into Upper and Lower Bahariya members, and it consists mainly of sand layers occupying the lowermost of the Bahariya section while the stacking sandy shale layers are common in the upper part. The thickness of each Upper and Lower Bahariya members along the study area ranged from 201 feet to 305 feet and 330 feet to 417 feet respectively. The Upper Bahariya Cenomanian section is dominated by shale and siltstones and thin streaks of moderate to good reservoir quality sandstones occur in this section but with questionable lateral continuity. The late Albian/ Early Cenomanian, Lower Bahariya section is dominated by sandstone, siltstone, and shale. It is the main pay in Petroshahd development leases. The Bahariya Formation is differentiated from the underlying Albian Kharita Formation by its fine to very fine-grained, chloritic, and glauconitic sandstone. Otherwise, the top of the Kharita Formation is characterized by its silica cement and the absence of chloritic and glauconitic facies. The main objective of this study is the evaluation of hydrocarbon reservoirs in the Al Zahraa oil field based on using petrophysical characteristics, and identifying the sandstone distribution of the Bahariya Formation reservoir and it’s vertical and lateral changes.


Main Subjects

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