Suitable archaeological features would include hearths, kilns and other fired structures.
Small samples of soil or burnt building materials are prepared in situ by having small plastic discs glued to the surface of the layer.
Magnetism occurs whenever electrically charged particles are in motion.
The Earth's molten core has electric currents flowing through it.
As the earth rotates, these electric currents produce a magnetic field that extends outward into space.
This process, in which the rotation of a planet with an iron core produces a magnetic field, is called a dynamo effect.
Archaeomagnetic dating is based on the comparison of directions, intensities or polarities with master records of change.