The most extraordinary theories
There is the hypothesis according to which the mentioned 9 thousand years were transmitted as 9000 seasons with 121-122 days. In such case the events connected with Atlantis can be referred to the end of 4th century BC and are connected with such events as the damage of the Indo-European society and the beginning of the wide expansion.
Geographically all these events are connected with the regions that are situated near the Black Sea the level of which increased a lot during this period because of the destruction of the Bosporus by the Mediterranean waters. The most evident traces of this catastrophe are the name of the Sea and its unique two-level structure.
According to another theory Antarctica is the formed Atlantis. This theory is described in details in the book of the famous writer Gram Hancoke "The Traces of Gods". In opinion of the author Antarctica was transmitted to the area of the South Pole in the result of the lithosphere shift. Before it was situated near the equator and wasn't covered with the ice.
There are also some unusual theories that Atlantis was destroyed by the aliens and that it was the ship of the aliens that left earth provoking the inundations that caused the talk about the destruction of Atlantis in the result of the natural disaster. But these stories are only the result of vivid imagination.