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In 1645 B.C., a volcano on Santorini erupted with such force that some believe it caused the collapse of the Minoan civilization on the island of Crete, 70 miles away. Thirteen cubic miles of material exploded into the sky. Settlements on Santorini were buried under a thick layer of ash thicker than the one that covered Pompeii. The explosion, estimated to be about the equivalent of 40 atomic bombs or approximately 100 times more powerful than the eruption at Pompeii, blew out the interior of the island and forever altered its topography. Possibly as many as 20,000 people were killed as a result of the volcanic explosion. [Source: Canadian Museum of History , William Broad, New York Times, October 21, 2003]

The main eruption was preceded by a smaller one — a shower of light pumice that buried the town of Akrortiri, down slope, under many feet of ash. This may have sent most of the residents away. No skeletons or human remains have been found on Santorini. The main eruption began when sea water entered a vent of the volcano and mixed with magma and gases, producing an ultra-violent explosion. The center of Thera collapsed into a sea-filled caldera. Santorini was buried Pompeii-style under ash, up to 900 feet deep, that preserved frescoes and wall paintings that recorded everyday life from the period and contained Egyptian motifs.

The explosion produced a huge tsunami, possibly a 100 meters (300 feet) high. This tsunami swamped and hit the coast of North Africa, sending water 330 kilometers (200 miles) up the Nile. On Crete, an 50-foot-high tsunami wiped out coastal settlements. Inland ash may have ruined crops and grass that fed livestock.

According to the Canadian Museum of History: “Historians have been debating for years about exactly when the major eruption at Thera took place. Radio-carbon dating and dendrochronology (tree-ring dating) had narrowed the date down to a range of years but neither could confirm a specific year. Then improvements in the science of ice core dating made it possible to pinpoint a particular year-1646 B.C. - a century earlier than most historians had thought. (Ice cores drilled out of the Greenland ice cap show seasonal variation in the same manner as tree rings. The winter snow fall creates yearly bands and within that band the atmospheric activity is recorded. The volcanic eruption at Thera was confirmed as happening in 1646. At the present time, the core depth allows scholars to look back in time some 200,000 years and work will continue on making that timeline longer.)” |

Killer Tsunamis From Thera

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Thera from Santorini
The massive eruption of the Thera volcano produced tsunamis that tore across hundreds of kilometers of the Eastern Mediterranean to inundate the area that is now Israel and probably other coastal sites, a team of scientists reported in the October 2009 issue of Geology. William J. Broad wrote in New York Times: Geologists judge the eruption as far more violent than the 1883 eruption of the volcanic island of Krakatoa in Indonesia, which killed more than 36,000. The team did its excavations off Caesarea, Israel, a coastal town dating from Roman and Byzantine days. The coastal region was only sparsely settled at the time of the Thera eruption, with no identifiable city. [Source: William J. Broad, New York Times, November 2, 2009]

“The team sank a half-dozen tubes into the offshore seabed and pulled up sediment cores for analysis. It looked for standard signs of tsunami upheaval, including pumice (the volcanic rock that solidifies from frothy lava), distinctive patterns of microfossils, cultural materials from human dwellings and well-rounded beach pebbles that seldom appear in deeper waters. Writing in Geology, a journal published by the Geological Society of America, the team reported finding evidence of three tsunamis — two historically documented ones dating to A.D. 115 and 551, and one from the time of the Thera eruption.

“The Thera tsunamis, the team wrote, left a signature layer in the seabed of well-rounded pebbles, distinctive patterns of mollusks and characteristic inclusions in rocky fragments all oriented in the same direction. The disturbed layer, up to 16 inches wide, came from a few feet below the seabed in waters up to 65 feet deep. “These findings,” the team wrote, “constitute the most comprehensive evidence to date that the tsunami event precipitated by the eruption of Santorini reached the maximum extent of the Eastern Mediterranean.” The team added that, if the giant waves were big enough to reach Israel, “then presumably other Late Bronze Age coastal sites across the Eastern Mediterranean littoral will likely have been affected as well.”

Thera Volcano and the End of Minoa

The Thera eruption may have been the largest eruption on Earth in the last 10,000 years. Some scientists have calculated was 90 times greater than the one at Mount St. Helens and four times greater than Krakatau, which killed 36,000 people . Some say it was much larger than that, perhaps even larger than Tambora, which erupted in 1816 and produced the year without summer and famines in the United States.

After the Thera eruption 50 foot tsunamis smashed against Crete’s shores, smashing ports and fleets and severely damaging in the maritime economy, which was vital for the Minoans as it was an island civilization. Ash levels of 10 feet were recorded 20 miles away on the island Anafi. That was incredible amount of ash that distance away.

In 1939 Greek archaeologist Spyridon Marinatos theorized that eruption of Thera caused the collapse of Minoan civilization with damaging earthquakes and tsunamis. Some doubts were raised about earthquake side of the story because earthquakes associated with volcanic eruptions are usually not that strong. In the mid 1960s scientists dredging up sediments found thick layers of ash linked to Thera’s eruption and found it covered thousands of square miles.

But the theory was given a blow in 1987 when the date of the eruption was set at 1645 B.C. based in the presence of frozen ash in Greenland ice cores, 150 year before the pervious dates, and 200 years before the steep decline of Minoan culture. The theory was given another blow in 1989 when a Minoan house was found built above the ash layer.

Now the reasoning goes the eruption took time to bring down Minoa. Some archaeologists say the eruption and tidal waves did not destroy Minoa rather it weakened, making it vulnerable to conquest. An the Mycenaeans were the ones who conquered it. They theorize the that ash from the eruption could have destroyed crops, brought about a famine, opening the way for a conquest from the Mycenaeans.

A century earlier a large earthquake destroyed the palace of Knossos. It was rebuilt. An earthquake that occurred around the time of the Thera explosion damaged the palace. In the decades that followed all the major palaces of Crete were damaged by fire, most likely by invaders.

Ash from the Thera eruption

By 1450 B.C. nearly all Minoan palace-cities, except Knossos were mysteriously destroyed. Around this time pottery styles and writing styles changed reflecting styles introduced from Mycenae, suggesting that the Mycenaeans took over Crete. By the 14th century B.C., Knossos appeared to be under the administration of the Mycenaeans.

Impact of Thera Eruption on the Eastern Mediterranean

The Thera eruption had a dramatic affect on the eastern Mediterranean that lasted for decades, even centuries. Dense clouds of volcanic ash and deadly tsunamis were generated over a huge area, crippling ancient cities and fleets, setting off climate changes, and sowing political unrest.

The Thera eruption produced two large ash clouds. One that was blown by lower atmosphere winds to the southeast towards Crete and Egypt and another that was blown by the jet stream in the stratosphere to the northeast over Anatolia (Turkey). Dr. Peter Kuniholm, a tree ring expert at Cornell, found that trees found in an Anatolian burial mound grew three times faster that normal for about half a decade around the time of eruption, presumably because the ash turned the region’s normally hot, dry summers into ones that were unusually cool and wet.

But although the ash seems to have helped trees it is thought it severely damaged wheat fields and reduced harvests. Many think it was the primary factor behind Mursilis, king of the Hittites, setting out from his Anatolian kingdom and attacking Syria and Babylon, which lay between the two plumes, and seizing their stored grains and cereals. This in turn prodded Babylon towards collapse and hurt one of its allies, the Hyksos, who ruled Egypt and traded with the Minoans.

The plagues described in the Bible are thought by some to be a result of the Thera volcano. The explosion and land submerged by the tsunami may be the source of Plato’s story of Atlantis. Some scholars speculate that ancient Minoa or Thera may were have been Atlantis, which Plato, supposedly heard about from Socrates who in turn heard about it from Egyptians. Some historians believe the Thera eruption changed the entire coarse of history. With Minoans out of the picture, they hypothesize, cultures on the Balkan peninsula were able to develop into classical Greece.

Santorini Caldera produced by the Thera eruption

According to the BBC: The cataclysmic Thera eruption happened 100 kilometers from the island of Crete, the home of the Minoans. Fifty years after the eruption, that civilisation was gone. Did the volcano wipe out the Minoans and if it did what exactly took place? Jessica Cecil wrote for the BBC: “Early 20th-century archaeologists knew of the devastating volcano and some concluded it must have snuffed out the Minoan civilisation almost instantly. But was it really as simple as that? For a start, they discovered little ash had fallen on Crete - as luck would have it, the prevailing winds took the volcano's ash in the opposite direction. Then archaeologists found clay tablets that proved the Minoan civilisation survived for about 50 years after the eruption. So if the volcano killed the civilisation, what accounted for this long gap? [Source: Jessica Cecil, BBC, February 17, 2011 |::|]

Tsunami Destruction and the Massive Size of the Thera Eruption

Jessica Cecil wrote for the BBC: Vulcanologist Floyd McCoy from the University of Hawaii “was convinced that giant waves, or tsunamis, had been unleashed by the volcano. He believed these waves travelled across the open sea to batter the northern coast of Crete - but proof was hard to find. In 1997 a young British geologist, Dr Dale Dominey-Howes of Kingston University, found what he believes is firm evidence of tsunamis on Crete. He drilled deep into the mud at an inland marsh near Malia in Crete, and took the mud core he found back to England for analysis. |[Source: Jessica Cecil, BBC, February 17, 2011 |::|]

“The mud had been deposited, layer upon layer, over thousands of years. At one place, deep in the core, Dr Dominey-Howes found a type of tiny fossilised shell that only lives in very deep sea water. He felt sure the shells were brought into the marsh by an ancient tsunami. A Minoan palace near the marsh was buried at the same level as the shells, suggesting the tsunami could have hit soon after the palace was built. |::|

“If a tsunami had been unleashed by the eruption of Thera, Floyd McCoy wanted to know how big it might have been. He turned to Professor Costas Synolakis of the University of Southern of the world's top predictors of tsunamis... He estimated that waves from Thera battering northern Crete could have been up to 12 meters high in places. Such waves would have destroyed boats and coastal villages, even travelling up rivers to flood farmland. |::|

“But however terrifying these waves, they can only have been part of the story. McCoy was convinced the volcano must have had wider effects. A remarkable discovery by a British geologist gave rise to a new theory - that the volcano already classed as one of the most devastating of the last 10,000 years could have been even bigger than scientists had previously thought. |::|

Nile delta's elevation cross section shows how vulnerable it is to a tsunami

“Professor Steve Sparks of Bristol University found clues in the smallest fragments of evidence. He was surprised to find clumps of fossilised algae high on the cliffs of the volcano. These algae only live in shallow waters, and their presence suggested there was once a shallow sea inside the crater of the volcano. If there had been a shallow sea, Professor Sparks realised, the shape of the volcano could have been entirely different, and a differently shaped volcano could have produced far more ash. His hunch was that the volcano could have been twice as powerful as geologists had suspected.” |::|

Cycle of Disaster Following the Thera Eruption

Jessica Cecil wrote for the BBC: “What might a volcano of this size have meant for the Minoans on Crete? Volcanoes throw up sulphur dioxide, and huge amounts of this gas can alter the climate. Climate modeller Mike Rampino at New York University calculated that the eruption on Thera could have lowered annual average temperatures by one to two degrees across Europe, Asia and North America. Rampino believes the summer temperatures would have dropped even more, suggesting years of cold, wet summers and ruined harvests. [Source: Jessica Cecil, BBC, February 17, 2011 |::|]

“Rampino's calculations were supported by the work of Professor Mike Baillie of the Queen's University, Belfast. Ancient logs preserved for millennia in Irish bogs contain a record of the weather - and especially the cold, wet periods that stunt trees' growth. Trees that were growing at the time of the eruption - 3,500 years ago - show signs that the climate was especially wet and cold then. |::|

“Floyd McCoy believes the volcano undermined the Minoans for years. First, it destroyed an entire island that had been crucial to their trade. Then, giant waves battered the Minoan coasts, destroying coastal villages and boats at harbour. Next, the Minoans faced summers of ruined harvests. |::|

“Knossos archaeologist Colin MacDonald thinks the effects of these disasters were compounded by something more - the Minoans began to see their world in a different way. MacDonald believes the Minoan people, stripped of their certainties, stopped obeying the priest kings in palaces like Knossos. This marked the start of a 50-year decline for the entire Minoan civilisation. They were in no position to fight back when Greeks from the mainland took control of the island.” |::|

End of the Minoans

According to the Canadian Museum of History: “Around 1450 B.C. the Minoan civilization, which appears to have been peaceful and prosperous, came to an abrupt and probably violent end. There is evidence of wholesale destruction by fire and there has long been speculation that a volcanic explosion at Thera (followed possibly by a tsunami) created s April 5, 2006 great civilization of the Aegean world. That hypothesis has now been called into question as recent studies of ice core samples push the Thera eruption further into the past. [Source: Canadian Museum of History ]

Colette Hemingway and Seán Hemingway of the Metropolitan Museum of Art wrote: “From 1500 B.C., there was increasing influence from the Mycenaean culture on the Greek mainland, and there is clear archaeological evidence for widespread destruction on the island around 1450 B.C. If the Mycenaeans were not responsible for this destruction, they certainly took advantage of the events—administrative records from this period are written in Linear B, the script of Mycenaean Greeks. Contemporary pottery shows a blend of Minoan and Mycenaean stylistic traits. Eventually, by the beginning of the eleventh century B.C., the Minoan culture on Crete was in decline.” [Source: Colette and Seán Hemingway, Metropolitan Museum of Art, October 2002 \^/]

Akrotiri: the Minoan Pompei

Outside of Fira on Santorini itself are the ruins of Akrotiri, a Minoan settlement, that was buried Pompeii- like by the Thera eruption. The leader of the excavation died in 1974 when he fell in one of the excavations and hit his head. Few artifacts have been found which means the people fled before the volcano erupted. Only a small area has been excavated from the hardened volcanic ash, revealing houses with that are now in the Athens Archeological Museum.

map of Akrotiri

According to the Canadian Museum of History: “Just as happened at Pompeii centuries later, a settlement on Thera known as the town of Akrotiri was buried under a thick blanket of ash and pumice. For more than 3,500 years the ancient Bronze Age community lay hidden- one of Greece's many secrets of the past. Then, as is often the case with various heritage sites, the town of Akrotiri was accidentally discovered. Quarry workers, digging out the pumice for use in the manufacture of cement for the Suez Canal, chanced upon some stone walls in the middle of their quarry. These eventually proved to be remains of the long-forgotten town. Archaeologists from France and later from Germany did some preliminary excavation in the second half of the 19th Century but it was not until 1967 that systematic excavation began at the site in earnest. Spyridon Marinatos, supported by the Archaeological Society of Athens, soon began to uncover the remains of the ancient town. It was not easy. Not only were the buried buildings two or even three stories tall, the original building materials (clay and wood) had been damaged by earthquakes, fire and the hands of time. It was necessary to proceed slowly and carefully. Work on the project has now been on-going for almost four decades and it is likely to continue into the foreseeable future.

“The site has yielded some surprising information. Most startling of all is the fact that no human remains have been found at Akrotiri, unlike Pompeii and Herculaneum where the dead were buried in the midst of their daily activities. At Akrotiri, it was obvious that people had begun to do some repair work to their dwellings, probably in response to minor earthquake or volcanic damage. However, before the major eruption at least some of them had the time to pack up their families and most valuable possessions and leave. Huge pottery containers and large household furnishings were abandoned in their haste to depart but it seems clear that most people got away safely, were buried elsewhere or were swept away by the tsunami waves that might have accompanied such a massive eruption." |

Akatoriki excavation

Jessica Cecil wrote in for the BBC: “Akrotiri's chief archaeologist, Christos Doumas, believes the people of Akrotiri didn't survive, and that the bodies are still to be uncovered, huddled at the harbour where they were trapped by the eruption as they waited to escape. He believes it's highly unlikely that scores of boats were waiting in the harbour to save them. [Source: Jessica Cecil, BBC, February 17, 2011]

“The Akrotiri site has not yielded huge amounts of gold, silver and bronze artifacts, nothing on the scale that might have been expected had the inhabitants been caught unawares. But a splendid visual legacy was left, most of it in pieces that are painstakingly being assembled by Christos Doumas and his colleagues. The frescoes at Akrotiri are spectacular, were exceptionally well-preserved by the protective blanket of ash that covered them and their locations can be correlated to various rooms within the town.

The paintings provide a lot of visual information that needs to be carefully analyzed- a fleet of ships manned by sailors allowing one to see how the vessels were rigged, how the crew was dressed, what they carried by way of tools and weapons; people in the community going about their daily activities, picking flowers, making religious offerings; two nude fishermen carrying strings of fish; young boys in a boxing match, etc.” |

Discovery of Minoa

The Palace of Knossos and Minoan culture were discovered in 1900 by Sir Arthur Evans, an Englishman who had come to Crete to search for information about the origins of Mycenaean culture.

Akrotiri blue monkeys
Evans traveled to Crete several ties between 1894 and 1899. He began his search at the mound of Kephala, outside Heraklion, where seals with Mycenaean-like marking were found. Twenty-five years he finished excavating the 5½ acre Knossos Palace.

Evans used his own personal fortune, worth several million dollars in today's money, to finance the dig. Based on the presence of numerous images of bulls and the maze -like quality of the palace, he decided that Knossos was the source of the Minotaur myth and labyrinth story. He also found written scripts which he labeled Linear A and Linear B.

Evans work as an archeologist was shoddy to say the least. He replaced missing columns and support beams with reinforced concrete. Archaeologists that followed found concrete covering up the original gypsum and sandstone. In the original excavations and Evan did not indicate different time periods.

Other important Minoan sites include the Gorge of the Dead, an unplundered palace found in 1962 by Nicoloaos Platon in Zakros; a Bronze Age settlement on Santorini preserved like Pompeii found on Spyridon Marinatos; burial chambers of a queen or priestess found in Arkhanes; the grand stair case of Phaistos, the central court at Mallia, and the throne room of Knossos.

Image Sources: Wikimedia Commons, The Louvre, The British Museum

Text Sources: Internet Ancient History Sourcebook: Greece ; Internet Ancient History Sourcebook: Hellenistic World ; BBC Ancient Greeks ; Canadian Museum of History ; Perseus Project - Tufts University; ; MIT, Online Library of Liberty, ; Metropolitan Museum of Art, National Geographic, Smithsonian magazine, New York Times, Washington Post, Los Angeles Times, Live Science, Discover magazine, Times of London, Natural History magazine, Archaeology magazine, The New Yorker, Encyclopædia Britannica, "The Discoverers" [∞] and "The Creators" [μ]" by Daniel Boorstin. "Greek and Roman Life" by Ian Jenkins from the British Museum.Time, Newsweek, Wikipedia, Reuters, Associated Press, The Guardian, AFP, Lonely Planet Guides, “World Religions” edited by Geoffrey Parrinder (Facts on File Publications, New York); “History of Warfare” by John Keegan (Vintage Books); “History of Art” by H.W. Janson Prentice Hall, Englewood Cliffs, N.J.), Compton’s Encyclopedia and various books and other publications.

Last updated September 2018

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