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Electromagnetic methods are used to determine electric conductivity of the subsurface. There are two-coil systems and time-domain systems (transient electromagnetics).

Application examples:

  • Detection and demarcation of old hidden waste sites
  • Tracing of fissures and fault zones in bedrock
  • Survey and monitoring of pollutant dispersals (plumes)
  • Detection of buried metallic objects (drums, barrels, containers)
  • Detection of near surface pipe and cable service lines as well as hidden fundaments in industrial brownfields
  • Detection of ammunition and UXO (unexploded ordnance)

Depth of penetration: (dependent on measurement method) 2 m up to 400 m

Field use of EM61 device

Field use of a transient electromagnetic device

In field surveys the areas or profiles are placed in lines using the particular two-coil system. Depending on the operating system one or two technicians are needed. One big advantage of many electromagnetic methods is a low manpower and a high measurement progress (sometimes up to several kilometers a day).

Result of a pipeline exploration

Result of a pipeline exploration

For interpretation conductivity data is displayed in colours. The illustration shows the result of a successful pipeline exploration. The pipeline (highlighted in red) emerges clearly in the measured area.