Twin-electrode resistivity
Definition
A resistivity configuration using one mobile pair of contact electrodes and one remote pair. Current is injected and the voltage drop across the measurement electrodes reflects the resistance of the soil volume between them. Compact, useful for one-person forensic surveys.
Related terms
- Apparent resistivity
- The resistivity value computed from a measurement assuming the ground is homogeneous. In practice the ground is layered and variable, so apparent...
- FEM (frequency-domain EM)
- A class of instruments that measure ground conductivity from above-surface, without electrode contact, by inducing eddy currents with an oscillating EM field....
- Fluxgate gradiometer
- An instrument that measures the vertical gradient of the Earth's magnetic field using two fluxgate sensors mounted on a staff at fixed...
- Magnetic susceptibility
- A measure of how strongly a material is magnetised by an external field. Topsoil heated by fire or biological activity has elevated...
- Wenner array
- A four-electrode resistivity configuration where all four electrodes are equally spaced. Depth of investigation is approximately equal to the electrode spacing. Provides...
Explained in
- Magnetometry and Earth ResistanceA resistivity configuration using one mobile pair of contact electrodes and one remote pair. Current is injected and the voltage drop across the measurement el...