EM 34
Ground Conductivity Instrument

Case Histories 

Features
  • Excellent for mapping deeper groundwater contaminant plumes and for groundwater exploration.
  • Applications include obtaining vertical electrical soundings.
  • Very sensitive to vertical geological anomalies.
  • Widely used for~gr~atet~ tion in fractured, faulted and weathered bedrock zones.
  • In regions of high cultural and atmospheric noise, the higher powered EM343XL improves the signal to noise ratio by a factor of 10 at the 40m spacing, and by 4 at the l0m and 20m spacing.
General

The EM 34-3 is a fast, simple to operate, cost-effective instrument for the engineering geophysicist, geologist and hydrogeologist alike. The unit has been particularly successful for mapping deeper groundwater contaminant plumes and for groundwater exploration.

Using the same patented inductive method as the EM 31, the EM 34-3 uses three intercoil spacings to give variable depths of exploration down to 60 meters. With the three spacings and two dipole modes (horizontal as shown and vertical), vertical electrical soundings can be obtained. In the vertical dipole (horizontal coplanar) mode the EM 34-3 is very sensitive to vertical geological anomalies and is widely used for groundwater exploration in fractured, faulted and weathered bedrock zones.

In regions of particularly high cultural and atmospheric noise, the higher powered EM 34-3XL improves the signal to noise ratio by a factor of ten at the 40m spacing, and by four at the 10m and 20m spacing.

The EM 34-3 comes complete with an output connector for digital data logging with the DL 720, as well as input ports that can be used with a rechargeable battery option.

Specifications

Intercoil Spacings & Operating Frequencies:

10m at 6.4kHz
20m at 1.6kHz
40m at 0.4kHz
Power Supply:

Transmitter: 8 disposable or rechargeable "D" cells
Receiver: 8 disposable or rechargeable "C" cells
Dimensions:
Receiver Console: 19.5 x 13.5 x 26cm
Transmitter Console: 15 x 8 x 26cm
Coils: 63cm diameter
Shipping Case: 74 x 74 x 29cm
Weights:

Instrument Complete: 20.5kg
Shipping: 43kg
Measured Quantity:
Apparent conductivity in millisiemens per meter (mSIm)
Primary Field Source:
Self-contained dipole transmitter
Sensor:
Self-contained dipole receiver
Reference Cable:
Lightweight, 2 wire shielded cable
Conductivity Ranges:
±10, 100, 1000 mS/m
Measurement Precision:
±0.1% of full scale deflection
Measurement Accuracy:
±5% at 20 mS/m
Noise Level:
0.2 mS/m (can be greater in regions of high power line interference)

Standard Components


Standard system includes transmitter console and coil, receiver console and coil, transit case, and instruction manual.

Ordering Information

Description Order Number
EM 34-3 400-180-0003
EM 34-3XL 400-180-0006
Rechargeable Batteries 400-180-0012
DL 720 Data Logger 400-180-0039
EM Mapping System 400-180-0162
EMIX Modeling Software 200-201-0015