Magnetic survey in the Selinunte Archaeological Park

Geophysical methods are a common tool used in the search for archaeological evidence before excavation. In the Selinunte Archaeological Park, two test sites have been prospected with a fluxgate gradiometer and a proton magnetometer in gradiometric configuration. Many difficulties arose during data acquisition due to the small magnitudes and the low signal-to-noise ratio. The paper presents techniques for eliminating i) isolated values, ii) the systematic stretching of isolines in the N-S direction, iii) discontinuities in the average trend of contiguous subzones. In spite of such improvements, it was necessary to use a numerical process to increase the signal-to-noise ratio in order to single out and locate anomalies. Bidimensional cross-correlation was employed using theoretical models calculated specifically for the sought anomalies. It proved possible to define the sample zones where excavation could be carried out.