Proton Magnetometer - Proton Magnetometer in Archaeology

Proton Magnetometer in Archaeology

According to Christopher S. Peebles (Glenn A. Black Laboratory of Archaeology, Indiana University, Bloomington, Geophysics at the Angel Site: Past, Present, and Future) in 1958 Black and Mr. Eli Lilly, following the work of M. J. Aitken and his associates at the Oxford University (UK) Archaeometric Laboratory, used proton magnetometers to locate and map buried archaeological features. Magnetometers measure minute differences in the magnetic field of the earth caused by ferrous concentrations (and iron objects) in the soil, thermo-remnant magnetism of fired clays, and differences in the magnetic susceptibility of disturbed soils. In 1959, with the support of the Indiana Historical Society, Black rented a general purpose magnetometer. It proved a bit better than previous magnetometers for locating very large features, but was not really suited to archaeological work. In 1959, with the support of the Society, Black purchased a magnetometer built specifically for archaeological work from the Oxford Archaeometric Laboratory".

"In 1961 and in 1963 the National Science Foundation awarded funds to Black and to the Indiana Historical Society to evaluate the magnetometer as a tool for archaeological research. During 1961-1963, more than 100,000 square feet (9,300 m2) of the Angel site were surveyed and more than 7,000 square feet (650 m2) were excavated, in order to match anomalous magnetometer readings with the archaeological features that produced those readings. For the most part the strategy was to locate and follow the course of the stockade trench, but other features, such as houses, fire basins, and pits, were sought and located as well. This work, which was the first systematic use of a proton magnetometer for archaeological research in North America, was reported by both Johnston and by Black".