magnetic method

It uses one gradiometer sensor to measure spatial changes in the Earth’s magnetic-field gradient. The instrument is carried at a constant height along regularly spaced survey lines, commonly within rectangular grids, to produce detailed magnetic-anomaly maps. It is particularly sensitive to shallow archaeological features whose magnetic properties differ from the surrounding soil, including kilns, hearths, pits, ditches, disturbed deposits, walls and metallic objects.

Fluxgate gradiometry

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