Integrated Core Analysis and Wireline Logging for Characterizing Rock Properties in Selected Reservoirs of X Field, Niger Delta

Abstract

The present study characterises reservoir characteristics in selected reservoirs in the X Field, Niger Delta Basin, using a standard core analysis and wireline log interpretation. Wireline logs in LAS format, containing gamma ray, resistivity, density, neutron, acoustic, and calliper logs, were utilised in tandem with conventional core data to identify lithofacies, interpret depositional environments, and calibrate petrophysical responses. Ten reservoir units (R1–R10) were found throughout the field using reservoir delineation and well-to-well correlation. The Larionov gamma ray methodology for shale volume, density-derived porosity estimation, and Archie's equation for water saturation were among the industry-standard techniques used in the petrophysical investigation. With porosity values ranging from 0.076 to 0.321, the results show substantial reservoir variability, indicating insufficient to outstanding storage capacity. Shale volume ranges from 0.055 to 0.855 and water saturation ranges from 0.018 to 0.894, showing different reservoir quality and clay content. Significant hydrocarbon potential is indicated by reservoirs with high porosity (>0.300), low shale volume (<0.220), and low water saturation (<0.090). Well 3 R4 and Well 4 R3-R4 are two examples. On the other hand, intervals like Well 4 R1 and Well 5 R1-R3 have low reservoir quality and are rich in shale and water. Facies that depict offshore to delta-plain environments, including laminated shale, bioturbated shale, tidal sandstone, distributary-mouth-bar sandstone, and shoreface deposits, were discovered by core investigation. Depositional facies have a significant impact on reservoir quality and distribution in the Niger Delta Basin, as demonstrated by the significant improvement in reservoir characterisation brought about by the integration of core and log data.