Tsunami destruction
Pumice rains down at AkrotiriPumice rains down at Akrotiri on Thera after the volcanic eruption around 1600BC ©Floyd McCoy 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.
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.
Waves from Thera battering northern Crete could have been up to 12m high in places.
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 California.
Professor Synolakis grew up on Crete, playing amongst the palace ruins as a child. He became one of the world's top predictors of tsunamis, travelling the world with his computer models to predict the waves of tomorrow.
Professor Synolakis can also use his technology to determine the size of a wave from the ancient past. He estimated that waves from Thera battering northern Crete could have been up to 12m 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.
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
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