ERDFIII_Thermal demagnetizer

A thermal demagnetizer is a laboratory instrument used in paleomagnetic research to progressively remove the natural remanent magnetization (NRM) of rock samples by heating them to controlled temperatures and then cooling them in a near zerofield environment. This process, known as thermal demagnetization, helps to isolate different magnetic components acquired at various geological times. The device typically consists of a non-magnetic furnace that can heat samples up to 700–800°C with precise temperature control. After each heating step, the remaining magnetization of the sample is measured using a magnetometer. By analysing how the magnetization changes with increasing temperature, researchers can determine the stability and origin of magnetic signals, aiding in reconstructions of past geomagnetic fields and tectonic processes.