Combined GPR and seismic refraction tomography to study the subsoil in the Cathedral of S. Giorgio Ragusa- Ibla (Sicily)

In this work, we show GPR surveys combined with a series of seismic refraction tomographies to study the subsoil in the Cathedral of S. Giorgio in Ragusa Ibla (Sicily). The church stands on a high structural level characterized by a carbonate formation, consisting of a calcarenite-marly succession. Built in the 18th century, where previously stood the church of San Nicola, the new building probably hosts, under the present flooring, several tombs of different ages and probable remains of the oldest previous church. The combination of the two geophysical methods here proposed allows us to highlight the potential of each technique and how they perfectly support the reconstruction of the subsoil of the church with different details on archaeological and geological/structural buried structures.