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A lone diver first laid eyes on the ancient wreck of the Kyrenia off the northern coast of Cyprus almost 60 years ago. But when archaeologists tried to determine the exact timeline of the ship’s coming to rest on the ocean floor, they had to speculate about the basis of the ship’s cargo.
Now, a new study published Wednesday in the journal PLOS One may have a better estimate of when the Kyrenia disappeared — and the revelation came thanks to recently cleaned wood samples from the ship, as well as clues provided by a twig, an animal bone. and a cache of old almonds.
Local diver Andreas Cariolou first discovered the ship Kyrenia, one of the first major Greek ships from the Hellenistic period to be found largely intact, in 1965, and a team led by the late marine archaeologist Michael Katzev searched the wreck and its cargo at the end. 60s.
Researchers originally thought the ship sank around 300 BC. A text, first volume of the site’s final reports published in 2022, estimated a range of 294 BC to 290 BC, based on pottery and some coins found on board. But according to the latest study, no scientific dating was available to support these estimates.
Excavations of the ship Kyrenia
The authors of a new study dated almonds found aboard the Kyrenia ship to find a new estimated range of years for which the ancient ship’s last voyage took place.
Using radiocarbon dating — a method used to determine the age of organic materials, such as the wood of trees — and dendrochronology, the science of dating tree rings, researchers in the new study determined that the The sinking of the Kyrenia had occurred between 296 BC and 271 BC. And they found a high probability that it happened between 286 BC and 272 BC, the study authors wrote.
“We got dates very close to those that archaeologists have recently suggested, but only slightly more recent,” said lead author Sturt Manning, distinguished professor of arts and sciences in classical archeology at Cornell University in New York.
While an updated timeline supported by scientific data is important for the famous ship, the crucial revelation lies in new techniques and a revised radiocarbon calibration that can help scientists more accurately date structures and wrecks from this period, Manning said.
According to Manning, there were two main obstacles to making an accurate estimate of the age of the Kyrenia wreck. The first was that polyethylene glycol or PEG, a petroleum-derived compound used to preserve the ship’s wood, interfered with radiocarbon dating.
Often, wrecks remain well preserved due to the lack of oxygen on the ocean floor. But once the materials rise to the surface, they deteriorate quickly, Manning says. Injecting polyethylene glycol into the wood prevents the wood from crumbling and turning into powder, but it then becomes difficult to remove over time.
“Just have literally a fraction of a percent of this stuff (polyethylene glycol) in there, and the date will be off, often by hundreds or even thousands of years,” said Manning, who attempted to date Kyrenia. shipped 10 years ago but failed due to PEG.
However, an international team of researchers developed a cleaning protocol, described in an October 2021 study, that successfully removed the petroleum-based compound from wood that was preserved fairly recently, Manning said. To confirm that the protocol would work with something as old as the wreck of the Kyrenia, Manning and his colleagues applied the technique to a piece of PEG-preserved wood that they knew came from nearly 2,000 years old and found precise radiocarbon ages.
Using a solution to clean the wood, researchers believed they could date the ship’s wood. But they ran into a second obstacle and continued to receive ages that didn’t fit “any possible archaeological solution,” Manning said.
After investigation, he and his team determined that the Northern Hemisphere International Radiocarbon Calibration Curve, the conversion of measurements to dates based on known tree rings, was obsolete for the period between about 400 and 250 BC.
The researchers were able to formulate their date estimate by recalibrating the curve using samples of redwoods and oaks of known age from that period. The revised curve was key to determining a precise time period for the Kyrenia’s sinking and could further help researchers around the world facing similar problems when dating ancient structures, Manning said.
Radiocarbon ages of the wood gave researchers an idea of when the ship was built, but it was a cargo of almonds that gave the study authors an estimate of when the ship sank, Manning said. “If you have materials like almonds – or you can imagine olives or something like that that were used as a food crop – and they were on the ship when it sank, it must have been there for probably about a year… or maybe it was two years older than when a ship sank.
Using organic materials from the cargo, such as almonds, an unidentified wooden twig that was not part of the ship’s construction, and a cattle ankle bone, the researchers were able to refine the dates and estimate a range of ‘years for when the ship was transported. The final voyage of the ship Kyrenia has taken place.
Excavations of the ship Kyrenia
The hull of the ship Kyrenia is visible shortly after being lifted from the seabed and reassembled.
“Part of the value of this story is the process. … the fields of (radiocarbon) dating and dendrochronology have grown, developed and refined their results over many decades,” Mark Lawall, a professor in the department of classics at the University of Manitoba in Winnipeg, said in an email. “Science, whether ‘hard’ or ‘soft,’ develops over time through considerable ‘on the ground’ work. It takes time and it requires time.” He was not involved in the new study.
With the slight change in the estimated date of the sinking, it is impressive that the original dates based on archaeological evidence from ceramics and coins were only off by a few years, said Lawall, who studied the amphorae, ancient Greek containers used to ship wine and olive oil. and other goods from the wreck of the Kyrenia.
“The other part of Kyrenia’s story is its window into past lives that are otherwise difficult to ‘see’ through well-known (or even lesser-known) ancient writers,” Lawall said. “Kyrenia’s crew may have been a band of more marginal traders, taking what they could, where and when they could, and hoping for a small profit at the end of the day. »
He added: “They were intervening across cultures and, in doing so, were part of an extremely complex network that linked all parts of the Mediterranean. In this way we begin to understand the origins of the modern, multicultural and interdependent Mediterranean world.