Paleomagnetism
The study of the historical record and orientation of Earth's magnetic field preserved in iron-bearing minerals in rocks, sediments, or archaeological artifacts.
Governing formula
Remanent Magnetization Vector (Declination & Inclination)
SI unit
Degrees (° Declination / Inclination)
In depth
Ferromagnetic minerals (like magnetite) cooling below their Curie temperature (~580 °C) freeze in the local direction and inclination of Earth's magnetic field at that time. Paleomagnetism provided critical evidence for seafloor spreading and polar wander.
Examples in the real world
Reconstructing past continental locations and continental drift paths over hundreds of millions of years.