DOCUMENTATION AND MONITORING OF UNDERWATER ARCHAEOLOGICAL SITES USING 3D IMAGING TECHNIQUES: THE CASE STUDY OF THE "NYMPHAEUM OF PUNTA EPITAFFIO" (BAIAE, NAPLES).

The preservation status of an underwater cultural site can be determined as the combination of two primary factors, namely the site physical integrity, which results from the past and present interaction of the site itself with the biological/chemical agents located in the surrounding environment, and the exposure of the site to human-related threats. Methods to survey underwater archaeological sites have evolved considerably in the last years in order to face the challenges and problems in archaeological prospection, documentation, monitoring, and data collection. This paper presents a case-study of an archaeological documentation campaign addressed to study and monitor the preservation status of an underwater archaeological site by combining the quantitative measurements coming from optical and acoustic surveys with the study of biological colonization and bioerosion phenomena affecting ancient artefacts. In particular, we present the first results obtained in the survey and documentation campaign carried out during the spring - summer 2018 in the "Nymphaeum of Punta Epitaffio" located in the Marine Protected Area - Underwater Park of Baiae (Naples).