Lithological characterization of the subsurface layers at ‘NASS’ field, Choba, Rivers State

Abstract

The study on lithological characterization of subsurface layers at ‘NASS’ field, Choba, Rivers State has been evaluated. However, the study deployed the use of electrical resistivity survey (Schlumberger Array Configuration method) in investigating the subsurface lithological layers. This method is efficient for characterizing the layers in terms of understanding the variations in lithology, the resistivity properties and changes with depth, andthe depth to portable water Formation as depth increases. The acquired field data was used to produce a resistivity curve for subsurface interpretation. The study investigated five stratigraphic layers and four thicknesses. In this way, the first layer has resistivity values of 84.7Ωm (at a depth of 1.6m); layer two has 689.2Ωm (at 2.7m); layer three has 8,593Ωm (at 14.1m); layer four has 3273Ωm (at 46.8m) and layer five has 791.1Ωm (at a depth greater than 46.8m) respectively. The aquifer formation is at a depth of 46.8m for the extraction of potable water in the area. The results above were used to produce a geoelectric section based on the resistivity properties of the different layers. The section produced revealed lithological layers that are characterized by good geological properties for groundwater exploration.