Archaeomagnetic dating is the study and interpretation of the signatures of the Earth's magnetic field at past times recorded in archaeological materials. These paleomagnetic signatures are fixed when ferromagnetic materials such as magnetite cool below the Curie point, freezing the magnetic moment of the material in the direction of the local magnetic field at that point in time. The direction and magnitude of the magnetic field of the Earth at a particular location varies with time, and can be used to constrain the age of materials. In conjunction with techniques such as radiometric dating, the technique can be used to construct and calibrate the geomagnetic polarity time scale.
The Earth's magnetic field reverses direction at irregular intervals, and local directions and intensities change gradually (secular variation). These changes can be used to constrain ages of baked materials.
Herries, A.I.R., Kovacheva, M., Kostadinova, M., Shaw, J., 2007. Archaeo-directional and -intensity data from burnt structures at the Thracian site of Halka Bunar (Bulgaria): The effect of magnetic mineralogy, temperature and atmosphere of heating in antiquity, Physics of the Earth and Planetary Interiors. 162, 199-216.
|
||||||||||||||||||||||||||||
|
|
Wikis
Quiz
Search
