Atlantis & Lemuria

"There occurred violent earthquakes and floods. And in a single day and night of misfortune... the island of Atlantis disappeared in the depths of the sea."This account, written by Plato more than 2,300 years ago, set scientists on the trail of the lost city of Atlantis. Did it ever exist? And if so, where was it located, and when did it disappear?In a recent paper in Geology, Marc-Andre Gutscher of the European Institute for Marine Studies in Plouzané gives details of one candidate for the lost city: the submerged island of Spartel, west of the Straits of Gibraltar. The top of this isle lies some 60 metres beneath the surface in the Gulf of Cadiz, having plunged beneath the waves at the end of the most recent ice age as melting glaciers caused the sea level to rise. Geological evidence has shown that a large earthquake and a tsunami hit this island some 12,000 years ago, at roughly the location and time indicated in Plato's writings. Gutscher has surveyed this island in detail, using sound waves reflected off the sea floor to map its contours1.

His results bring mixed news to Atlantis hunters. Ups and downs At first, his conclusions seemed disappointing. At the time identified by Plato for the city's loss, the sea levelwould have been fairly high on the island's banks. According to sea-level measurements alone, Gutscher estimates the island "would have been reduced to wave-swept rocky islets" and would have been less than 500 metres in diameter, making it impossibly small for a sophisticated city. But there is a saving grace. Gutscher says the island might have sunk further since those times from seismic activity. Layers of turbidite, the sand and mud shaken up by underwater avalanches, suggest that eight earthquakes have happened in the area since Atlantis sank. Each earthquake could have resulted in a drop of the sea floor by several metres. So 12,000 years ago, Spartel might have been 40 metres higher than expected, and could have measured five by two kilometres. "This is aninteresting c......

"There occurred violent earthquakes and floods. And in a single day and night of misfortune... the island of Atlantis disappeared in the depths of the sea."This account, written by Plato more than 2,300 years ago, set scientists on the trail of the lost city of Atlantis. Did it ever exist? And if so, where was it located, and when did it disappear? In a recent paper in Geology, Marc-Andre Gutscher of the European Institute for Marine Studies in Plouzané gives details of one candidate for the lost city: thesubmerged island of Spartel, west of the Straits of Gibraltar.

The top of this isle lies some 60 metres beneath the surface in the Gulf of Cadiz, having plunged beneath the waves at the end of the most recent ice age as melting glaciers caused the sea level to rise. Geological evidence has shown that a large earthquake and a tsunami hit this island some 12,000 years ago, at roughly the location and time indicated in Plato's writings.Gutscher has surveyed this island in detail, using sound waves reflected off the sea floor to map its contours1. His results bring mixed news to Atlantis hunters.At first, his conclusions seemeddisappointing. At the time identified by Plato for the city's loss, the sea level would have been fairly high on the island's banks. According to sea-level measurements alone, Gutscher estimates the island "would have been reduced to wave-swept rocky islets" and would have been less than 500 metres in diameter, making it impossibly small for a sophisticated city.

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Atlantis! No geologist can hear the name without mixed emotions. The ancient legend, forwarded to us by Plato from Egyptian sources, is difficult to translate and analyze, and a thick crust of speculation and outright hooey surrounds any truth in it.On the other hand, it describes the destruction of an island city by earthquake and tsunami.A conference in July 2005 gathered researchers, including geologists, on the Greek island of Milos to discuss Atlantis. At least a dozen candidates for the site of Atlantis were presented, ranging from Ireland to India. But to my mind the mostinteresting place is right where Plato said it was, "near the Pillars of Hercules," in a locality that spawns great earthquakes and tsunamis. In 2002 a team led by French researcher Marc-Andre Gutscher reported in Geology on the Gulf of Cadiz, the bay just west of the Strait of Gibraltar—which all agree is the "Pillars of Hercules" Plato referred to.

A detailed seafloor survey of the gulf showed the unmistakable pattern of a subduction zone and a thick wedge of sediment, or accretionary arc, building up in front of it. Gutscher wrote that this subduction zone "must be considered as a possible source of the great M>8.5 earthquake and tsunami that ravaged Lisbon and the Gulf of Cadiz in 1755." At the Milos conference, "Atlantis 2005," Gutscher presented more recent research into a large submerged island in the Gulf of Cadiz named Spartel Bank. Asit happens, he has just published the same work in Geology. He took key data from Plato's account: a date 9000 years before 600 BCE or 11,600 years ago; an island about 15 kilometers across; a location in the sea beyond the Pillars of Hercules; the sinking of the Atlantean city beneath the waves in a single day leaving a muddy shoal behind. These facts fit a scenario based on new geologic data about that time and place. At that time, sea level was more than 100 meters below its present elevation and Spartel Bank was an island. In fact, Gutscher's new mapping of the site shows that it would have been a rather small island at that time, smaller than previously thought. But things change when we add the effects of large subduction earthquakes. As we all know from the Sumatra quake of 2004, large areas of land sink by several meters and more during these events. If werestore th......

An international congress devoted to the myth of the lost continent of Atlantis opened on the Greek island of Milos, attended by seismologists, geologists, geographers, philosophers, historians and archaeologists from five existing continents."We're not trying to establish whether Atlantis existed or not, or to agree on a definite location, which would be presumptuous for a talethat has existed for over 2,500 years," Spyros Pavlidis, a professor of palaeoseismology at the Aristotelio University of Salonika, told AFP."Our objective is to hear all hypotheses, take stock of all reliable data, and examine the sources of inspiration," he said. Pavlidis, one of the congress organisers, said that contributions from some speakers were rejected for being "too fantastical." The seismology professor personally sees in the Atlantis tale told by the fourth century BC Greek philosopher Plato "anallegory on the decline of a civilisation, with the hint of a true story at its core." But he admits that most of the participants, who include independent researchers as well as university academics, in the three-day congress "are leaning towards believing the story, and seek to find the city." Contribution themes range from "The quest for Atlantis: the utopia of an utopia" to "Atlantis was Israel".Article Source .