Use of integrated geophysical methods to investigate a coastal archaeological site: the Sant’Imbenia roman villa (northern Sardinia, Italy)

We report here a multimethod geophysical investigation of the Sant'Imbenia Roman villa archaeological site in northern Sardinia (Italy). The main objective of this study is optimizing a non-invasive approach to reconstruct rapidly the geometry of coastal sites. A hitherto unexplored area of approximately 700 m2, adjacent to excavations, was investigated using ground-penetrating radar (GPR) and electrical resistivity tomography (ERT) surveys. The Sant'Imbenia villa is close to the present-day shoreline and subject to very high erosion rates and burial. A comparison of the high-resolution GPR and ERT models was made, and their integrated results are discussed in terms of providing a more complete picture that would not be attainable using a single method. Geophysical analysis combined with archeological prospecting has revealed buried buildings north of the excavated part of the archaeological site. The results show that in this coastal environment ERT survey provided the most accurate reconstruction at the deeper wet levels of investigation.