Most people would have heard about the mythical disappearance of Atlantis. Even researchers believe that the ancient Iapetus Ocean never existed at all. However, Warren Huff, a geologist at the University of Cincinnati, USA, has found evidence of a narrow Iapetus Ocean from ancient volcanic ash beds. He says that the Ocean did exist during the Ordovician but closed off and disappeared by the Silurian 420 million years ago.