Studio dell’efficacia dell’OhmMapper (Geometrics Inc.) per indagini geoelettriche in contesti archeologici

The research project carried out during the PhD work aims to study the effectiveness of the OhmMapper (Geometrics Inc.) capacitive-coupled resistivity system in archaeological contexts. In order to verify the effectiveness of this resistivity-meter to identify archaeological features, we realized a systematic surveys in the Geophysical Test Site of Rovereto (TN - Italy). In particular we compared both resistance and resistivity profiles realized by OhmMapper capacitively coupled resistivity-meter and by the Terrameter SAS 1000 (ABEM) galvanic resistivity meter. We realized these surveys walking along the same acquisition line to intercept a target compatible with an archaeological feature. The comparison between the profile realized by the two different instruments allowed us to establish the reliability of the OhmMapper to detect targets characterized by vertical pattern and resistivity values grater than the context. After this analysis, we realized several resistivity surveys in archaeological sites using the OhmMapper. In particular the surveys carried out in five archaeological sites are the most appropriate to demonstrate the effectiveness of the instrument, because the resistivity results are comparable with other archaeological or geophysical data. Two of these sites are located in modern urban contexts (Sacred Area of Medma Greek colony and the roman Aqueduct of Florence); the other three sites are located in suburban areas (Late-ancient villa near Siena, Accademia of Villa Adriana and Sentinum roman town).