Geophysical Signatures of a Roman and Early Medieval Necropolis

International audienceThe Roman and early medieval Richeaume XIII necropolis in Provence (France) was systematically studied using magnetic prospection and electrical resistivity tomography (ERT). Remains of a limestone‐made building are embedded in a reddish clay formation bearing iron oxides. This produces an interesting negative magnetic anomaly, whereas the wall itself is resistive. Other dipolar magnetic anomalies are correlated with the location of sepulchres, either covered by roman, strongly magnetized tegulae, or corresponding to burnt layers of cremations. After normal data processing, filtering and modelling are applied to the magnetic field data in order to more precisely define the sources. Constraints using ERTsoundings, magnetic property measurements, archaeological and geological data help to build such a source model. This study particularly emphasizes that magnetic prospection combined with ERT profiles should be suitable and sufficient on other necropolis sites in the same geological environment