EM31 can detect up to 6 meters in depth with a broad resolution
We also own a Geophex GEM-2 which can detect deeper than 6 meters, but has lower resolutions, usually applied to niche cases. Though can also be adjusted to recording high frequencies, detecting very small anomalies in the near-surface.
Distinguish high resistance sands against low resistant organic layers
Follow leachate flows, excellent at detecting problem areas for focused studies
2D or 3D profiles can be performed using resistivity testing for deeper studies of contaminant plumes from tailings