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Geonics EM38

This instrument was designed to measure the electrical conductivity of the soil to about 1.2m depth using the quadrature response of the ground to an electromagnetic wave. The inphase response is representative of the magnetic properties of the ground & is analogous to the magnetic susceptibility.

There are four modes of operation:

instrument vertical (vertical dipole) quadrature
instrument vertical (vertical dipole) inphase
instrument horizontal (horizontal dipole) quadrature
instrument horizontal (horizontal dipole) inphase

In horizontal dipole mode the response is sensitised to about 0.4m depth whereas in vertical dipole mode the response decays exponentially with depth. The most recent version of the instrument, pictured here, is the EM38BRT, the BRT indicating that both quadrature & inphase responses are measured simultaneously & the data is available in real time.

Manufacturer

Geonics Ltd, Canada

Web site

http://www.geonics.com