Premium
Lightning strikes and prehistoric ovens: Determining the source of magnetic anomalies using techniques of environmental magnetism
Author(s) -
Maki David
Publication year - 2005
Publication title -
geoarchaeology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.696
H-Index - 44
eISSN - 1520-6548
pISSN - 0883-6353
DOI - 10.1002/gea.20059
Subject(s) - hearth , geology , rock magnetism , archaeomagnetic dating , lightning (connector) , remanence , environmental magnetism , magnetization , excavation , earth's magnetic field , geophysics , mineralogy , archaeology , paleontology , magnetic field , geography , sediment , physics , power (physics) , quantum mechanics
Techniques of environmental magnetism were used to examine soil samples from a North American archaeological site in an effort to determine the source of magnetic field gradient anomalies. Testing revealed the source of one anomaly to be lightning‐induced remanent magnetization (LIRM). This anomaly had initially been identified as a possible archaeological feature, but excavations were unable to identify a visible source. LIRM appears to be a relatively common source of anomalous signal on archaeological sites and may often be misinterpreted in magnetic imagery. Thermoremanent magnetization (TRM) was also documented and quantified in soil from archaeological hearths at the site, as were changes in the ferrimagnetic mineral concentration and coercivity spectra resulting from high‐temperature enhancement within the hearths. © 2005 Wiley Periodicals, Inc.