GEM-3 Broadband EMI Sensor

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Download Software

• GEM-3 manual

• WinGEMv3

• Conversion of ppm data to conductivity & susceptibility

• 1-D inversion

GEM is a Registered Trademark

GEM-3 Broadband Programmable Electromagnetic Sensor

The GEM-3 produces inphase and quadrature data at each          frequency. Inphase data is sensitive to earth’s electrical            conductivity and magnetic susceptibility. Therefore, over                    highly conductive and/or magnetic soil, the inphase data                 is often too sensitive to sensor height to be a stable detection          indicator. 

The quadrature data, however, are insensitive to the height variations and, thus, provide reliable detection. The sum of all quadrature data is an excellent detection indicator in magnetic and/or conductive geology.

Technical Specifications

Programmable Operation

Bandwidth:                         300 Hz to 96 kHz

Frequency Domain:             Single frequency

                                         Multiple frequencies

Typical sampling rate:         30 Hz            

Removable sensor head:     Sealed fiberglass, 1 kg

Sensor head diameters:      30 cm, 40 cm, 64 cm, 96 cm

Rechargeable battery          12 VDC

Output:                              Inphase and quadrature in ppm

                                         Apparent conductivity

                                         Magnetic susceptibility

                                         Powerline amplitudes

Realtime GPS input for navigation

Remote operation options – vehicle towed, for instance

Program upload and data download: WinGEM

Ppm to conductivity and susceptibility conversion

GEM-3 40cm

GEM-3 64cm

Geophex, Ltd. 605 Mercury St., Raleigh. NC 27603, USA; (919) 839-8515