Numis Lite - Magnetic Resonance Sounding System (MRS)
The Numis lite device is a Magnetic Resonance Sounding (MRS) system for the direct detection of shallow groundwater down to 50 m of depth.
This compact MRS equipment features:
- a converter/tuning unit powered by two 12 V batteries,
- a transmitter-receiver unit for pulse generation and signal measurement,
- a wire loop used as a transmitting and a receiving coil,
- a PC computer for the control of the whole system, and for data processing and interpretation
The MRS method is the only non-invasive method which directly studies groundwater reservoirs from surface measurements:
A pulse of current, at a given frequency is transmitted into a loop. The protons of the groundwater are excited. The signal produced during their return to equilibrium is measured with the same loop. To realize a sounding, different pulse moments (A.ms) are injected in the loop, all corresponding to different investigation depths.
This measure gives access to the soil water content (%) and is related to the mean pore size (permeability).
Transmitter
Voltage: 0 - 2000 Vpp
Current: 0-150A
Pulse moment: 100to6000A.ms
Battery: two external 12V
Receiver
sampling frequency: 4 times the Larmor frequency
Channel: 1 channel
noise level: Lower than 10nV/VHz
Dimensions
(LxWxH) DC/DC Converter: 40 cm x 30 cm x 33 cm Tx/Rx main unit: 43 cm x 30 cm x 30 cm
weight: 2x20Kg
Operating Temp.: -20 to +70°C