One of the largest volcanic eruptions of the Holocene era – as measured by the volume of ejected material – occurred on the Greek island of Santorini, traditionally known as Thera. Considered a pivotal prehistoric event in the Aegean and eastern Mediterranean, the city of Akrotiri was buried some 1,600 years before Pompeii, becoming one of the major archaeological sites in the second millennium BC. This much is indisputable.
Archaeologists in the early twentieth century hypothesized that the volcano erupted around 1500 BC, during the period of the Egyptian New Kingdom, and created a history around this assumption. But beginning in the 1970s, advances in radiocarbon dating threw this timeline into disarray, with many experts insisting the eruption occurred more than 100 years ago.
Sturt Manning, Distinguished Professor of Arts and Sciences in Classical Archeology in the College of Arts and Sciences, hopes to settle one of the ancient controversies in modern archeology. By analyzing the available data and combining it with sophisticated statistical analysis, he focused on a much narrower range of eruption dates: around 1609-1560 BC, during Egypt’s preceding Second Intermediate Period, when the Hyksos – a Canaanite dynasty of origin – controlled Lower Egypt. Although no exact date of the year has been set to resolve the big picture question of the correct historical period, the result illustrates many years of debate.
“This was the single most controversial date in Mediterranean history for more than 40 years,” said Manning, who directs the Cornell Tree-Ring Laboratory. “It was one of those endless feuds, that people just say, ‘There’s a problem here, we can’t solve it, let’s move on.’ I hope with this paper people will suddenly go, ‘You know what, that’s actually limiting He defines the problem in a way that we couldn’t do before, and narrows it down to where, usefully, we can say it’s in the second transitional period. So we should start writing a different history. “
For Manning, the eruption of Thera was like Mount Everest – a challenge he had wanted to face since the beginning of his career. Accurate event dating has become more feasible in recent years with the increasing complexity of Bayesian statistical analysis, enabling temporal modeling that can incorporate vast amounts of data and archaeological observations to better define the probability parameters of an unknown event.
Manning said the criteria have been fairly well understood for years, thanks to the extensive geological and archaeological research that has been conducted. The missing piece of the puzzle has long been a concern raised that volcanic carbon dioxide emissions could contaminate organic samples from Thera and cause incorrect age assessments.
Last spring, Manning realized he could solve the problem by looking elsewhere – hundreds of kilometers from Thera – to the Aegean regions that had suffered the effects of the tsunami caused by the explosion. Manning included the dates obtained for these episodes in his model for testing and discounting the volcanic carbon dioxide warning. At Thera itself he also discovered the significance of a short but clearly noticeable time gap between the abandonment of the city at Akrotiri and the mega-eruption, and this previously ignored limitation was incorporated into the modeling.
“It has been noted for years that there was a short period of time in the archaeological sequence between the date of Akrotiri’s abandonment and before it was buried under meters of pumice from the eruption. Although several hectares were excavated, no human skeletons were found, so it is clear That people had warned of impending danger and left. No one was allowed to do that in the past,” Manning said. “By putting in this additional qualification, we are tightening the statistical analysis.”
Modeling has determined the most likely range of eruption dates to be: around 1609-1560 BC (95.4% probability), or around 1606-1589 BC (68.3% probability).
The new timeline synchronizes the civilizations of the eastern Mediterranean while also ruling out several auxiliary theories, such as the idea that the eruption of Thera was responsible for the destruction of Minoan palaces on the coast of Crete as the first Akrotiri excavator, Spyridon Marinatos, was proposed in 1939.
“It appears that this is not the case,” Manning said. “Because when we chronicle the levels of devastation in Crete, they seem to have risen a century later.”
Because his analysis links the eruption of Thera earlier than the proposed original date, but not as early as radiocarbon dating initially suggested, Manning hopes the new timeline will be more acceptable to experts on both sides of the long-running debate.
“This shows, as with a lot of science, that people have to make hypotheses based on raw information, but as you get more and more information and better analysis, you revise and revise,” he said. “In this case, the answer appears to be between the original position and the first radiocarbon indices pointing back as far as 100-150 years. We hope that this new analysis, based on a large data set and a more recent and better defined radiocarbon calibration curve. 2020, it should be more palatable for the overall archaeological and historical domains. It changes the historical context, but at the same time it doesn’t try to take things out of the way.”