Black Sea Chemistry. But 650 feet below the surface of the Black Sea, there is no oxygen in the water for the wood bores to breathe, says Ballard. He compared the sea to a giant bathtub, with steep sides and no drain.Because the water of the Black Sea is very still, oxygen doesn’t circulate to the bottom.The Black Sea, he says, is the perfect environment for preserving shipwrecks. The researchers predict there are perhaps hundreds still to be found.ecause the water of the Black Sea is very still, oxygen doesn’t circulate to the bottom. The Black Sea, he says, is the perfect environment for preserving shipwrecks. The researchers predict there are perhaps hundreds still to be found.