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2G Superconducting Rock Magnetometer

The 2G Enterprises Rock Magnetometer 755 R was installed as system no. 67 (755-1.65UC ) at the University of Bremen in June 1997. The instrument determines the natural remanent magnetization of a sample in terms of intensity and direction. This information may provide insight into the history of the Earth’s magnetic field and allow for an estimation of the age of the sample.

Synthetic laboratory remanences imparted by the device allow for the characterization of the magnetominerals carrying the magnetic information.

The system is designed to process U-channels with a maximum length of up to 150 cm as well as discrete samples with a volume of up to 10 cm³. It employs dc SQUID sensors with a total magnetic moment noise level of les than 10E-9 emu (10E-12 Am²).

When expressed in terms of magnetization, the dc SQUID based rock magnetometer has a noise level of less than 10E-7 A/m for a 10 cm³ volume rock. In rock magnetometer systems, the SQUID is used to measure current induced in superconducting pickup coils placed at the center of the rock measurement region.

There are three sets of of such pickup coils, two for transverse moment measurement and one for axial moment measurement, thus the total magnetic moment is determined at a time.

The System consists of further components such as:

  • In-line 3-axes alternating field demagnetizer (peak field 170 and 300 mT)
  • DC coil to impart ARM in peak fields of 0.4 mT
  • DC pulse coil to impart IRM in peak fields of 800 mT


  • Pneumatic autosampler for discrete samples
  • Additional DC coils to compensate for remaining fields inside the magnetometer
  • Temperature monitoring of AF coils
  • Replacement of genuine stepper motor by HDY series servo motor (PARKER Automation) combined with compact servo controller COMPAX 1000SL incorporating power stage, control electronics, integral position controller and a direct-on-line- power supply for significantly safer and more accurate positioning
  • Customer-developed monitoring and processing software based on National Instruments LabVIEW
  • Online presentation of all data and all relevant measurement and system parameters
  • Full control by script files to perfom fully automated series of different measurements
  • Customer-developed paleomagnetic interpretation software

CAD drawings:

For more specific information contact:

Frederichs, Thomas, Dr.+49 421 218-65326GEO I, GEO 4040[Bitte aktivieren Sie Javascript]
Hilgenfeldt, Christian+49 421 218-65314GEO 1, 4110[Bitte aktivieren Sie Javascript]