Study of Industrial Disturbances Affecting Magnetic Prospecting Data in Archaeological Sites

The study of industrial disturbances was focused on “static” sources made of iron and reinforced concrete (e.g. water pipes, stakes), and “active” or electromagnetic-field producing elements (e.g. electrical power lines, generators and geophysical equipment). The measurements and forward modeling provided the patterns and main parameters (amplitudes, gradient and blind-zone sizes) for magnetic anomalies of static disturbances. Forward modeling was also applied to an analysis of the demagnetization effect of highly magnetic objects and the  threshold, the latter being the rate at which the anomaly amplitude increases when that of the  values begins to slow down. The disturbig effect introduced by a non-stable electromagnetic field cannot be eliminated by single-sensor magnetometer measurements but can be suppressed by the use of a gradiometer survey.