Cookie settings

Geophysics

Electromagnetics (TDEM)

TAUBER experts rely on electromagnetics (TDEM) for applications with magnetic – yet non-metallic – interference, such as surfaces with recycled layers, basaltic substrates and brick debris. This method can also detect obstructions made of non-magnetic metals, such as brass.

Measuring principle

Messprinzip der Elektromagnetik

In electromagnetics, TAUBER uses state-of-the-art measuring systems with induction-based operating principles. The systems are basically composed of a transmitting coil and a receiving coil. During the measurement, an alternating current generates a primary magnetic field in the transmitting coil. In conductive obstructions, when the primary magnetic field is switched off, electric eddy currents which generate their own (secondary) magnetic field are excited. The receiving coil can register these changes in the secondary magnetic field and thus provides measurement data indicating a suspicious metal object.

Since this method excites the subsoil itself and analyzes its reaction, it is called an active geophysical process. Since the conductivity of the substrate is investigated, metallic but non-magnetic ammunition can be found.

The maximum depth for detecting weapons by means of TDEM depends mainly on the coil size, the object size and metallic obstructions or backfill in the vicinity of the object or in the subsoil. With TAUBER's mobile systems, it is possible to detect large objects up to a depth of three meters. A special large loop system can also detect large bombs up to five meters below the surface of the earth.

hb_tauber-073.jpg

The applied technology

Depending on the requirements, different coil sizes are used for clearing the ordnance. For example, the selection of measuring instruments extends from the mine detector for the examination of the upper ground layers during surface clearing, to various digital measuring systems with mobile coil frames of different sizes and time windows up to the large loop.

Areas of application

  • Surface detection
  • Surface detection with large loop for increased depth range
  • Large-loop borehole detection
  • Land clearance
Detektion Tisch
K. A. Tauber Spezialbau GmbH & Co. KG