The variable frequency electromagnetometer is a prospection system that provides the following information:
Penetration into the ground is inversely proportional to the frequency; lower frequencies reach greater depths, and the maximum depth depends on the average resistivity of the soil. The working frequency range of the equipment is approximately between 300 and 20,000 Hz, allowing measurements at multiple frequencies simultaneously.
The working process involves taking measurements at stations distributed according to the problem being studied. At each of these stations, simultaneous measurements will be taken at various frequencies. The quantity and magnitude of the frequencies used depend on the objective of each particular study.
The values obtained by this technique are compared with those obtained by other techniques, such as vertical electrical soundings and electrical tomography. Therefore, the calibration of the electromagnetometer is done by comparison with these values.