Message #244826

[Corissa]

Atlantis - Was it a gradual subsidence?
 
 
 Realistic theory?

One of the most prevalent theories concerning Atlantis was that it disappeared as part of a gradual subsidence. But is this a realistic theory and is there any evidence for it?
 


Gradual Subsidence.

Although Atlantis is said to have vanished beneath the waves in a relatively short time, there is evidence to indicate that some parts of the island took longer to submerge. Plato, and the Greek philosopher Aristotle, both agree that even in their day, the waters beyond the Straits of Gibraltar were unnavigable due to layers of very thick mud. The cause of this they believed was subsidence left behind from a sunken island.

Impenetrable Mud.

In the Timaeus and Critias Plato explains it as follows: "At that time, as we said, Atlantis was an island larger than Libya and Asia Minor combined, though it was subsequently overwhelmed by earthquakes and is the source of the impenetrable mud which prevents the free passage of those who sail out of the straits into the open sea."

In his book Meteorologica Aristotle also mentions "shallows due to mud" and Scylax of Caryanda likewise mentions a sea of thick mud just beyond the Pillars of Hercules. It seems that even as recently as 2300 years ago - which on the geological scale is barely an eye-blink - the Ocean beyond Gibraltar was unnavigable because of deposits of mud from a vanished island. Even today an examination of the sea bed at this point reveals an exceptionally high level of sedimentation.

Until now this was explained as the result of sediment carried by the powerful currents passing through the Straits of Gibraltar. Yet this would seem unlikely. The reason is that although the area around the Straits is relatively shallow, one does not need to progress far into the Mediterranean before encountering very deep waters. It means that sediment from the Mediterranean would be more likely to deposit itself against the rise of this slope, within the Mediterranean, rather than the Gulf Of Cadiz, outside it.

Other Evidence.

Similar evidence can be found further westwards. Around the island of Madeira we see a vast submerged chain of mountains named the Horseshoe Seamount. Southwards from here, and indeed throughout the whole of this area there is an enormous expanse of sedimential deposit covering wide portions of the surrounding sea-bed. The strange thing is there is nothing to account for this deposit - nothing that is, unless there was once a large area of land here that for some reason began to break apart and later submerged.

Wholesale submersion.

The sum total of this evidence implies that the Atlantis disaster may have been a much more recent affair than Plato is telling us. On the other hand perhaps the initial catastrophe, which destroyed Atlantis - or it's spiritual centre - was merely a precursor to the wholesale submersion of numerous other islands that once existed here. Their demise, like that of Atlantis was probably precipitated by the initial devastating catastrophe that could have led to a complete fragmentation of this entire chain of islands.