Design and Implementation of a Composite Array Resistivity Data Logger for High-Resolution 2D Inversion Modeling

The use of resistivity meters to model subsurface conditions is widespread. However, commercial instruments are mostly limited to conventional configurations, such as Wenner, Schlumberger, and dipole-dipole. Moreover, we cannot modify the program on the instrument. In this study, we designed and implemented a DC resistivity meter that can potentially be developed in the future and can be used in composite array configurations. This instrument uses a half-bridge SMPS as a power supply, which is capable of generating a large power, an Arduino Uno, and several sensor modules as part of a flexible and easy-to-program control unit. We conducted laboratory and field tests, comparing two types of configurations, namely Wenner and composite arrays (dipole-dipole and gradient). We then processed the data using ResIPy software, which enables displaying complex data sets in the form of 2D cross-sections and assessing the quality of post-processing data. We obtained good data with low RMS misfit that matched the synthetic media created in laboratory testing and compared well with previous research.