NIGER DELTA BASIN

The Niger Delta Basin is one of the most productive hydrocarbon regions globally, yet its complex depositional history, structural variations, and diagenetic processes present challenges 9 for reservoircharacterization and hydrocarbon exploration. This study integrates lithofacies analysis, mineralogical evaluation using X-ray diffraction (XRD), and petrophysical assessment to enhance the understanding of reservoir quality and hydrocarbon potential in the EstyWil-1 Well, located in the Northern Delta Depobelt. Lithofacies analysis indicates a transition from fluvial-deltaic to deep marine depositional environments, characterized by alternating layers of sandstone, shaly sandstone, sandy shale, and thick shale. Sandstone-rich intervals, particularly within distributary channels and delta-front facies, exhibit high porosity (25-32%) and permeability (500-1500 mD), making them favorable for hydrocarbon accumulation. In contrast, shaly interbeds and deep marine shale sequences serve as barriers that influencefluid flow and hydrocarbon entrapment. Mineralogical analysis reveals a predominance of quartz, along with kaolinite, illite, chlorite, and feldspar, all of which impact reservoir quality. High quartz content enhances porosity, whereas clay minerals, particularly illite and chlorite, contribute to permeability reduction. The presence of pyrite and carbonate minerals in deeper sections suggests reducing conditions, which favor organic matter preservation and potential hydrocarbon generation. Petrophysical analysis, incorporating gamma-ray, resistivity, neutron-density, and sonic logs, confirms the presence of hydrocarbon-bearing zones with low water saturation (Sw <40%) in productive intervals. Structural interpretations highlight the role of growth faults and rollover anticlines as primary trapping mechanisms that enhance hydrocarbon accumulation. By integrating sedimentological, petrophysical, and mineralogical data, this study provides a more comprehensive approach to reservoir characterization. The findings contribute to improved exploration strategies, optimized reservoir management, and enhanced oil recovery (EOR) techniques within the Niger Delta Basin.