Rock Magnetics Laboratory

puma-lab1The Paleomagnetic Unit and Magnetic Anysotropy (PUMA) lab has been updated in 2017 and is now equipped with a whole set of instruments for palaeomagnetic and magnetic fabric analysis.

 

The lab is currently managed by Carl Stevenson and Marco Maffione and is open to all staff members and students of the University of Birmingham, as well as to external visitors and people form industry.

The lab is currently equipped with the following instruments:

Anisotropy of low field magnetic susceptibility (AMS)

  • KLY-3S kappabridge (AGICO)

This induction bridge operates at variable fields between 50 and 450 A/m (Amper/meter) and a frequency of 875 Hz. It is used to calculate the anisotropy of magnetic susceptibility (AMS) of a rock sample by measuring the magnetic susceptibility along different directions. This technique is commonly used to study subtle rock fabrics that are too weak or ambiguous to detect using other conventional methods.

Susceptibility versus temperature (low field and high temperature)

  • CS-3 furnace apparatus for the KLY-4S system (AGICO) 

This apparatus operates in combination with the KLY-4S kappabridge to measure the variation of magnetic susceptibility with temperature. It can measure susceptibility during heating cycles from room temperature to 750°C, or using liquid nitrogen within the CS-L cryostat between room temperature and-195°C. Thermomagnetic curves can be used to identify the blocking temperatures of dominant magnetic mineral phases that contribute to the bulk susceptibility.

Palaeomagnetic analysis

  • JR-5 spinner magnetometer (AGICO)
    The JR-5 spinner magnetometer is used in palaeomagnetic studies to measure the remanent magnetization of discrete samples by rotating them at high speed (97 rpm) within a nearly zero field environment. It can operate in both manual and automatic mode and is suitable to measure both cylindrical and cubic samples. The JR-5 is able to cover a wide range of remanence intensity making it suitable to study both magnetically weak sediments and extremely magnetic volcanic rocks.
  • LDA5 demagnetiser (AGICO)
    The LDA5 demagnetiser is used to demagnetise discrete rock samples with a variable alternating field (AF) up to 200 mT. The LDA5 can perform either tumbling or static (3 axes) demagnetizations.
  • D-2000 demagnetiser (ASC Scientific)
    Alternating field (AF) demagnetised able to demagnetise multiple discrete samples up to a peak AF of 100 mT. The D-2000 is also used to impart anhysteretic remanent magnetizations (ARM) and partial anhysteretic remanent magnetizations (pARM).
  • MMTD 80 shielded oven (Magnetic Measurements Ltd)
    The MMTD80 oven is able to demagnetise up to 80 samples at one time using temperature up to 700°C. It has a magnetic scield body which allows to reduce the magnetic field in the oven down to few nano Teslas.

Palaeomagnetic field kit

  • Stihl portable rock drill
  • Pomeroy orienting tool for magnetic and sun compasses
  • Magnetic susceptimeter

Enquiries

Requests for using the facilities of the PUMA lab should be addressed to Carl (c.t.stevenson@bham.ac.uk) or Marco (m.maffione@bham.ac.uk).