Oceanographic surveys in the Black Sea during 1998, 2002, and 2004 in the framework of a French-Romanian joint project, and recently in the framework of the European project ASSEMBLAGE, complement previous seabed mapping and subsurface sampling studies undertaken in the Black Sea by various international expeditions. Until the Ryan and Pitman flood theory and prior to this project, it was proposed that the Black Sea was predominantly a fresh-water lake interrupted by possible marine invasions coincident with high sea level during the Quaternary.

From the recent surveys carried out on the western part of the Black Sea it is evident...