Electrical Resistivity Tomography 3D Survey for Ground Characterization, Applied to the Detection of UXO Buried Objects

This paper explores the integration of 3D Electrical Resistivity Tomography (ERT) and 3D Induced Polarization (IP) for detecting unexploded ordnance (UXO) in subsurface environments. The methodology leverages the conductive and chargeable properties of metallic UXO materials, providing a powerful alternative to conventional geophysical techniques such as Ground Penetrating Radar (GPR), Electromagnetics (EM), and magnetometry, especially in urban or noise-contaminated settings. Using high-resolution, multi-channel acquisition systems and advanced inversion software, detailed resistivity and chargeability models are constructed to highlight subsurface anomalies. A critical indicator is the dipolar signature-spatially correlated resistivity and chargeability anomalies-that characterizes metallic targets. Field case studies in Trento and Naples validate the method’s effectiveness, confirming its ability to identify small-scale UXO targets in challenging site conditions. Compared to 2D methods, the 3D approach enhances detection accuracy, eliminates interpolation errors, and captures complex geometrical features. The results support ERT3D-IP as a non-invasive, cost-effective, and adaptable solution for UXO detection, with broader implications for geophysical applications in civil and defense projects.