We asked what physical property of the Black Sea is uniquely beneficial to shipwreck hunters, including legendary undersea explorer Dr. Robert D. Ballard, famous for his discoveries of the Titanic, U.S.S. Yorktown, and German battleship Bismarck.
The Black Sea is the world's only large body of water to feature an anoxic layer of water along its bottom, a trait that works to preserve wooden wreckage, such as ancient sailing vessels. Anoxic means "without oxygen," and the Black Sea's anoxic layer prevents not only the oxidizing decay of wood, textiles, clay, or even food, but it also precludes the presence of aerobic organisms that feed on and destroy these otherwise perishable artifacts.
Ballard has led multiple expeditions to the Black Sea in the last four years, looking for preserved vessels and even settlements. Scientists theorize that the formation of the Black Sea may be the basis for the various "great flood" stories in Greek, Babylonian, and Judeo-Christian mythology.
According to the theory, melting glaciers caused the destruction of a natural dam that kept the Mediterranean Sea separated from an inland lake 7,500 years ago. With the dam compromised, saltwater flooded the lake region with amazing speed, creating not just the comparatively larger Black Sea, but also the anoxic layer at its lower depths.
Besides shipwrecks, Ballard also hoped to find the remains of camps or villages along the shores of the original lake, and he may have succeeded. In 2000, Ballard found evidence that suggested possible human habitation on land that is now underwater. This so-called "Site 82" is just one of several surprises that the Black Sea has given forth to explorers, thanks in part to an anoxic layer that keeps decomposition out and historical treasures in.