Petrophysical Characteristics of Coastal Swamp Depobelt Reservoir in the Niger Delta Using Well-Log Data

Abstract

Sonic, gamma ray, density and resistivity logs in the onshore Coastal Swamps of the Niger Delta are used in the determination of some petrophysical properties of the reservoir in the Coastal Swamp Depobelt in the Niger Delta. The parameters investigated were porosity, velocities, shear and compressional velocities, and Poisson’s ratio. The results of the analysis show that the reservoir is 66m sandstone thick having porosity range of 0.21 – 0.39 with average of 0.26; density ranges between 2.01 and 2.30 with average of 2.21g/cc; Poisson’s ratio range 0.33 – 0.45 with 0.40 as average value; shear-wave velocity Vs ranges from 718 to 1097 having average of 932.33 m/s, compressional-wave velocity Vp ranges from 2110 to 2570 with average of 2230m/s, Vp/Vs ratio ranges 1.96 – 3.18 with average value of 2.55; and Gamma-ray GR value ranges 62 – 105 having average of 90AP and Vs 718 m/s are indicative fluid-filled reservoir. The results of this work can be used for well drilling and petroleum production programmes, and for civil engineering work in the area of study.