A Shoal of mud is stated by Plato (Tim.25d) to mark the location of where Atlantis ‘settled’. Plato describes these shallows in the present tense, clearly implying that they were still a maritime hindrance in Plato’s day.
Three of the most popular translations clearly indicate this:
….the sea in those parts is impassable and impenetrable, because there is a shoal of mud in the way; and this was caused by the subsidence of the island.
…..the ocean at that spot has now become impassable and unsearchable, being blocked up by the shoal of mud which the island created as it settled down.”
…..the sea in that area is to this day impassible to navigation, which is hindered by mud just below the surface, the remains of the sunken island.
Since it is probable that Atlantis was destroyed around a thousand years or more before Solon’s Egyptian sojourn, to have continued as a hazard for such a period suggests a location that was little affected by currents or tides. The latter would seem to offer support for a Mediterranean Atlantis as that sea enjoys negligible tidal changes, as can be seen from the chart below. The darkest shade of blue indicates the areas of minimal tidal effect.
If Plato was correct in stating that Atlantis was submerged in a single day and that it was still close to the water’s surface in his own day, its destruction must have taken place a relatively short time before since the slowly rising sea levels would eventually have deepened the waters covering the remains of Atlantis to the point where they would not pose any danger to shipping. The triremes of Plato’s time had an estimated draught of about a metre so that the shallows must have had a depth that was less than that.
The reference to mud shoal resulting from an earthquake brings to mind the possibility of liquefaction. This perhaps what happened to the two submerged ancient cities close to modern Alexandria. Their remains lie nine metres under the surface of the Mediterranean.
Our knowledge of sea level changes over the past two and a half millennia should enable us to roughly estimate all possible locations in the Mediterranean where the depth of water of any submerged remains would have been a metre or less in the time of Plato.
The tidal map above offers two areas west of Athens and Egypt that do appear to be credible location regions, namely, (1) from the Balearic Islands, south to North Africa and (2) , a more credible straddling the Strait of Sicily. This region offers additional features, making it much more compatible with Plato’s account.
By contrast, just over a hundred miles south from that Strait, lies the Gulf of Gabés, which boasts the greatest tidal range (max 8 ft) within the Mediterranean.
The Gulf of Gabes formerly known as Syrtis Minor and the larger Gulf of Sidra to the east, previously known as Syrtis Major, were greatly feared by ancient mariners and continue to be very dangerous today because of the shifting sandbanks created by tides in the area.
There are two principal ancient texts that possibly support the gulfs of Syrtis as the location of Plato’s ‘shoal’. The first is from Apollonius of Rhodes who was a 3rd century BC librarian at Alexandria. In his Argonautica (Bk IV ii 1228-1250)(a) he unequivocally speaks of the dangerous shoals in the Gulf of Syrtis. The second source is the Acts of the Apostles (Acts 27 13-18) written three centuries later, which describes how St. Paul on his way to Rome was blown off course and feared that they would run aground on “Syrtis sands.” However, good fortune was with them and after fourteen days they landed on Malta. The Maltese claim regarding St. Paul is rivalled by that of the Croatian island of Mljet as well Argostoli on the Greek island of Cephalonia. Even more radical is the convincing evidence offered by Kenneth Humphreys to demonstrate that the Pauline story is an invention(b).
Both the Strait of Sicily and the Gulf of Gabes have been included in a number of Atlantis theories. The Strait and the Gulf were seen as part of a larger landmass that included Sicily according to Butavand, Arecchi and Sarantitis who named the Gulf of Gabes as the location of the Pillars of Heracles. Many commentators such as Frau, Rapisarda and Lilliu have designated the Strait of Sicily as the ‘Pillars’, while in the centre of the Strait we have Malta with its own Atlantis claims.
Zhirov[458.25] tried to explain away the ‘shoals’ as just pumice-stone, frequently found in large quantities after volcanic eruptions. However, Plato records an earthquake not an eruption and Zhirov did not explain how the pumice-stone was still a hazard many hundreds of years after the event. Although pumice can float for years, it will eventually sink(c). It was reported that pumice rafts associated with the 1883 eruption of Krakatoa were found floating up to 20 years after that event. Zhirov’s theory does not hold water (no pun intended) apart from which, Atlantis was destroyed as a result of an earthquake. not a volcanic eruption and I think that the shoals described by Plato were more likely to have been created by liquefaction and could not have endured for centuries.
>Nevertheless, a lengthy 2020 paper(d) by Ulrich Johann offers additional information about pumice and in a surprising conclusion proposes that it was pumice rafts that inspired Plato’s reference to shoals!<
>(d) (99+) (PDF) Resurrection of Atlantis Minoica: A new localization of the Akrotiri (Santorini, Greece) West House room 5 frescos in view of current geological findings. Part 2 | Ulrich Johann – Academia.edu<