Performance Evaluation for an Optimized Wenner (ALPHA, BETA, AND GAMMA) Arrays Using Synthetic Geological Models

Abstract

The study aimed at comparing the resolution and effectiveness of three-electrode arrays (Wenner-α, Wenner-β, and Wenner-γ) in the 2D Electrical resistivity method using Numerical analysis of geological models. Three synthetic geological models that simulate block-one dyke and water layer were generated using RES2DMOD software. The inversion used for the geological models was based on smoothness-constrained least-square inversion which was carried out with RES2DINV. The inversion results were imputed into surfer11 software to examine the image resolution, thereafter absolute percentage error (APE) was calculated to measure the effectiveness of the arrays. The result for the block-one model shows that the Wenner-β array has an APE of 14.45%, the Wenner-α array has an APE of 32.67%, and the Wenner-γ array with an APE of 29.15%. Similarly, for the dyke model, the Wenner-α array, Wenner-β array, and Wenner-γ array have an APE of 69.61%, 57.43%, and 45.49% respectively. However, the results for the water layer model show that the Wenner-α array has an APE of 17.11%, the Wenner-β array has an APE of 12.16%, and that the Wenner-γ array has an APE of 16.21%.  Wenner-α is expected to produce an image with the best resolution having the highest APE, henceforth APE suggests the resolution capacity of an array.