Equipment at Paleomagnetic Laboratory

Table of Contents

2G Enterprises 755R DC SQUID Superconducting Rock Magnetometer

The 755R uses DC SQUID (Superconducting Quantum Interference Detector) magnetic field sensors to measure rock magnetism. The SQUIDS measure the current induced in three orthogonal pick-up coils within the cylindrical unit, with a noise level of less than 10-9 emu (10-7 A/m for a 10cc volume rock). Presently, we are measuring 1 inch diameter drill cores, 1 inch and 0.5 inch long, as well as 1cc cubic sediment samples with this system. The measurement routines are PC-driven with comprehensive software.



Up to Table of Contents

Princeton Measurements Corporation Model 2900 Micromag Alternating Gradient Magnetometer

The Model 2900 Micromag AGM is a highly sensitive measurement system, capable of measuring hysteresis properties on a wide range of sample types and strengths. It utilizes an alternating gradient field to exert a force on a sample that results in a deflection of the sample within the field. This deflection is measured by a pizeoelectric sensing element mounted on the probe arm, and signals are carried to a PC connected to the magnetometer. Analysis is done through a comprehensive software package. Magnetic properties such as coercivity, coercivity of remanence, saturation magnetization and magnetization of remanence are routinely measured by students working for the Paleomagnetic Research Group.



Pictured here is the P1 (fine) probe inside the AGM with a typical sample on the probe's stage. The stage sits between two electromagnets housed in the magnetometer assembly. The pizeoelectric sensing element is situated at the top of the probe. Typical samples include carbonate sediments from the Eastern Equitorial Pacific (pictured here), sandstones and basalts from the High Canadian Arctic, and basalts from the Hawaiian-Emperor Chain.

Up to Table of Contents

Applied Physics System Model APS 520 3-Axis Fluxgate Magnetometer

The fluxgate magnetometer allows for the measurement of magnetic fields over a wide range of values, along three orthogonal directions with a compact probe. Four selectable measurement ranges (1, 10, 100, 1000 mOe) are available. Fields up to 1300 mOe can be measured before probe saturation. Resolution is on the order of 10-6 Oe (0.1 gamma).



Up to Table of Contents

AGICO KLY-4S Kappabridge with CS-3 furnace and CS-L low temperature cryostat

The KLY-4S Spinner Kappabridge is the world's most sensitive commercially available laboratory instrument for measuring anisotropy of magnetic susceptibility (AMS) as well as bulk susceptibilty in weak variable magnetic fields. The KLY-4S Kappabridge consists of the pick-up unit and control unit connected with a PC computer via RS-232 interface. The instrument represents a super-precise fully automatic inductivity bridge. It is equipped with automatic zeroing system and automatic compensation of the thermal drift of the bridge unbalance as well as automatic switching of appropriate measuring range. The measuring coil is designed as 6th-order compensated solenoid with an outstanding field homogeneity. The digital part of the instrument is based on microelectronic components, with the microprocessor controlling all the Kappabridge functions. The KLY-4S sensitivity is 2 x 10-8 SI, measuring field range is 3 to 450 A/m.
The CS-3 furnice apparatus allows the measurement of the temperature variation of magnetic susceptibility at temperatures ranging from room temperature up to 700 C, with the KLY-4S Kappabridge. The apparatus comprises a non-magnetic furnace and an electronic control unit. The specimen, about 0.25 cm3 in volume, is heated electrically (in air or argon) by a platinum element and the temperature is measured by a special platinum temperature sensor. The CS-L low temperature cryostat apparatus allows to measure temperature variation of magnetic susceptibility at low temperatures ranging from liquid nitrogen temperature (77 K) to room temperature. The measurement process is fully automated in the CS-3 Apparatus, being controlled by a computer.


Up to Table of Contents

Model TD-48 Thermal Demagnetizer

The Model TD-48 Thermal Demagnetizer is a large-capacity thermal specimen demagnetizer. Special shielding permits cooling of one batch of specimens while a second batch is heating. The cooling chamber (forefront of the picture) has additional shields that limit the maximum internal field to less than 10 gammas. The sample boat has two titanium trays capable of holding three rows of various sized samples. Ceramic endcaps on the sample boat fit snuggly in the vestibules of the ends of the oven chambers, eliminating the need for oven doors. Total demagnitization (heating and cooling) times range from 1 hour to 2.5 hours, depending on the temperature of demagnetization desired. It is possible to demagnetize samples at a temperature range between 50 - 700 degrees C.



Up to Table of Contents

Sapphire Instruments SI-4 Alternating Field Demagnetizer

The SI-4 AF Demagnetizer is capable of alternating field demagnetization of samples, as well as ARM and IRM generation. The unit is controlled by a front panel logic keyboard. Demagnetization steps can be set by the user to a desired value. The AC coil shield is a 3 nested layer shield that limits the maximum internal field to less than 10 nT when oriented E-W in the ambient geomagnetic field.



Up to Table of Contents

Other equipment available:

PmagHomeBack to Paleomagnetic Research Group Home Page
last update: October 10, 2003