Geology and bathymetry of Black Sea

The Black Sea forms in an enclosed basin, located between south-eastern Europe and Asia Minor. The basin was formed during the Miocene orogenies which uplifted the mountain ranges and divided the ancient Tethys Ocean into several brackish basins, including the Sarmatic Sea.

The Caspian, Azov, Aral and Black Seas are the remnants of this evaporated basin. The basin is divided into two sub-basins by a convexity extending south from the Crimean peninsula. The north-west of the basin is characterized by a relatively large shelf up to 190 km wide, which has a relatively shallow apron with gradients between 1:40 and 1:1000.

The southern edge around Turkey and the western edge around Georgia however, are typified by a shelf that rarely exceeds 20km in width and an apron that is typically 1:40 gradient with numerous submarine canyons and channel extensions. The Euxine abyssal plain in the centre of the Black Sea reaches a maximum depth of 2,206m just south of Yalta on the Crimean peninsula. The basin is connected to the Mediterranean Sea via the Turkish Straits System (TSS) in the south-west, which includes the Bosphorus and Dardanelles straits and the Sea of Marmara. The Black Sea is connected to the Sea of Azov in the north-east via the Kerch straits.