3D Seismic Data Interpretation and Static Reservoir Modeling of Mamuniyat Formation, I and R Oil Fields, Murzuq Basin, Libya

• Published in: Iraqi geological journal 2024-05, Vol.57 (1E), p.275-286
• Main Authors: Abukliesh, Mosab, Mostafa, Taher, El Din, Zein, Abdelhafeez, Tharwat
• Format: Article
• Language: English
• ISSN: 2414-6064; 2663-8754
• DOI: 10.46717/igj.57.1E.18ms-2024-5-29

The Mamuniyat Formation, located within the Murzuq Basin in western Libya, represents a hydrocarbon reservoir characterized by significant preservation quality. A 3D reservoir modeling method was used in this study to evaluate the Mamuniyat reservoir in the I and R oil fields in the Murzuq Basin. The study looked at the reservoir's structural configuration, facies distribution, and petrophysical parameters. The basic problem in those fields is the large number of dry holes. A 3D seismic survey along with geophysical well logs are the data provided to accomplish the present work. The structural model was constructed based on depth-structure maps derived from seismic data analysis, which revealed the presence of two influential faults affecting the targeted strata within the investigated area. Notably, the primary NNW-SSE-oriented normal fault assumes a critical role as a structural trap. By incorporating well logs and petrophysical parameter computations, facies and property models were established. Facies analysis identified two principal facies, namely sandstone and shale. Based on the analysis of well logs and core data, it has been determined that the Mamuniyat Formation mostly consists of sandstone, with a very small amount of shale ranging from 5 to 10%. The effective porosity values range from moderate (13%) to good (16%), whereas the oil saturation varies between 62% and 91%. Employing the three-dimensional static reservoir modeling technique facilitated the visualization of lithofacies distribution, effective porosity, and hydrocarbon saturation across the reservoir's lateral extent. Consequently, the analysis determined that the upper section of the Mamuniyat Formation predominantly comprises sandstone with a relatively limited proportion of shale. Moreover, this interval exhibits favorable petrophysical characteristics, including high porosity values and significant hydrocarbon saturation.