Évolution historique du prisme littoral du lido de l’étang de Thau (Sète, Sud-Est de la France). Mise en évidence par sismique réflexion très haute résolution

Abstract

Very high-resolution seismic data have been obtained recently, in the framework of the research programme PNEC (French National Programme of Coastal Environment), on the shoreline area of Sète (Mediterranean coast, South East France). These data provide an accurate picture of the internal structure of the shoreline body. Seismic results combined with data about the morphosedimentary evolution of the study area, vibrocore data and results from archaeological investigations yield clues to the historical evolution of the study area. Especially, it is pointed out that the functioning of the present-day shoreline, by comparison with the system built in classical times, is characterized by a severe reduction in sediment supply and in volumes of sand involved in the shoreline dynamics.