Analysing the submerged cargo of Torre Santa Sabina: An insight on the provenance of underwater amphorae

• Amphorae from the underwater site of Torre Santa Sabina were analysed using a meta-analytical approach. • Comparison with fragments from local production sites was performed to identify compositional correspondences for provenance studies. • Post-depositional alteration occurring in ceramic materials deposited in different burial environment were considered. • Most of the underwater samples are locally produced, others refer to productions from the Greek islands, Campania and North Africa. This research reports the results of the archaeometric analysis of a set of 53 fragments of amphorae from the underwater site of Torre Santa Sabina (Apulia, southeastern Italy) and from the two local production areas (Apani and Giancola), aimed at identifying compositional correspondences that may be indicative of the provenance of the underwater amphorae. Post-depositional alteration occurring in ceramic materials deposited in different burial environments (sea and terrestrial) were considered to define which chemical elements were more suitable for provenance studies. The results of microscopic and spectroscopic analyses provided information on the characteristics of the ceramic materials supporting the archaeological investigations. The cargo found in the Torre Santa Sabina seabed reveals considerable heterogeneity both in terms of the varieties of amphorae forms and textural characteristics of the ceramic bodies. From a petrographic point of view, a group characterised by a carbonate-rich matrix and another one with an iron-rich terrigenous matrix were identified. This subdivision is also reflected by the mineralogical and chemical composition of the potsherds. Similarities in the grain-size distribution of inclusions and in the presence of fossil microfauna, typical of the geo-lithological characteristics of this part of Apulia, emerged between some fragments found on the seabed and those from the Apani and Giancola, indicating these sites as potential production centres for part of the analysed cargo. A few fragments can be attributed to different areas of the Mediterranean and in particular to the Campania region, North Africa and the island of Corfu, supporting the interpretation of maritime trades in which Torre Santa Sabina was involved.