The crew made the discovery while mapping the floor of the sea with sonar and remotely operated vehicles (ROVs).
They were studying a period about 12,000 years ago when the Black Sea grew much larger, an episode that ultimately contributed to the preservation of the shipwrecks.
As temperatures warmed and sea levels rose, saltwater from the Mediterranean began spilling over a rock formation in the Bosphorus Strait.
âThe oxygen drops to zero below 150 meters, which is ideal for the preservation of organic materials,â Adams said.
View Images This shipwreck from the Ottoman period was discovered 300 meters below the surface of the Black Sea.
But the unusual water chemistry of the Black Sea dramatically slows rates of disintegration.
The wood of some ships was so well-preserved that chisel and tool marks were still visible on individual planks. »