Fig. 5. Reconstructed levels in the Mediterranean (M) and Black Seas (B), and their connections/isolations via the SOÇ-Dardanelles and SOI-Bosporus sill (S). On the left is a portrayal of the gradual inflow model (Degens and Ross, 1972; Deuser, 1972; Deuser, 1974) in which the first connection was made at 9,000 yrbp. The depth of the strait deepened slowly as global eustatic sea level continued to rise, leading to an acceleration in the strengthening of the Black Sea's salinity. On the right is our catastrophic flood model in which the Mediterranean broke through a barrier in the inlet at 7,150 yrbp and rapidly flooded a partly evaporated freshwater lake. Here increase in the Black Sea's salinity is shown to have been initially abrupt and then to have later decelerated.