What is Archaeophysics & Archaeomagnetism?

Archaeomagnetism as a term is most often associated with Archaeomagnetic Dating and the use of secular variation of the Earth’s magnetic field to date archaeological burn features (e.g. Herries et al., 2007; 2008). However, here it is defined in its broadest sense “the use of magnetic methods of analysis on and for the understanding of archaeological materials and deposits”. In its widest context it has also been used to refer to the magnetisation of any materials relating to archaeological times and archaeomagnetists often work on other mediums such as volcanics and lake sediments. While it is most widely known for its use in dating, but more recently it has been utilised for other purposes including site survey, sourcing, identifying fire and site use, and palaeoclimatic reconstruction. These applications have different site requirements, as discussed below. Two main methods of analysis exist: those that look at the direction and intensity of fossil remnant magnetisations, as in palaeomagnetism; and those related to looking at the mineralogy, grain size and concentration of minerals within a rock or sediment, as in mineral (aka rock or environmental) magnetism. In the later case, identification of these parameters is achieved by different types and strengths of laboratory-induced remnant magnetisations and/or heat into samples to see how they react or alter. Magnetic methods have, over the last 10 years, been increasingly used as a Quaternary method of analysis for a variety of applications including dating, sediment-source tracing, and palaeoenvironmental/climatic reconstruction. While these methods have been used on some archaeological sites, their application has been sporadic and their potential as a major tool for reconstructing archaeological data remains underutilized despite the easy of sampling, low cost of the analysis, and ability to answer a range of questions, especially when applied along with other methods such as micromorphonology (e.g., Herries and Fisher, 2010). For more information on Archaeomagnetic Methods see:

Archaeomagnetism: Herries 2009        Archaeomagnetic Dating     Other links