ERS (electrical resistivity survey)

An Electrical Resistivity Survey is a geophysical technique used to investigate subsurface conditions by measuring the resistance of soil and rock to the flow of electrical current. This non-invasive method helps identify variations in underground materials based on their electrical properties. It is commonly used for groundwater exploration, geotechnical site investigations, environmental assessments, and mineral or void detection. By placing electrodes into the ground and measuring voltage differences, resistivity surveys can produce a detailed profile or 2D/3D model of subsurface layers. Different materials—such as clay, sand, rock, or water-bearing zones—respond differently to electrical current, allowing for accurate interpretation of soil composition, moisture content, fractures, and buried structures. Electrical resistivity is a cost-effective and reliable tool for exploring beneath the surface without excavation, making it essential in civil engineering, hydrogeology, and environmental studies.