Santorini Eruption Radiocarbon Dated to 1627-1600 B.C.
by Walter L. Friedrich, Bernd Kromer, Michael Friedrich, Jan Heinemeier, Tom Pfeiffer, and Sahra TalamoScience, 28 April 2006: 548 Abstract Full Text PDF Supporting Online Material
This article published the results of our recent study to provide the most precise absolute date for great Plinian "Minoan" eruption on Santorini about 4000 years ago available so far, to 1613 +-7 years BC. It made the cover of Science in 2006, but the story behind starts 4000 years ago, or on a personal scale, in late 2002. The following is a short, mostly personal addendum to the story, from the point of view of the finder of the olive branch (Tom Pfeiffer).
Some background first: the Minoan eruption at around 1613 BC

Ruins of the Minoan city buried on Santorini near the village of Akrotiri

The famous ship fresco - a wall painting from the Minoan city possibly representing the island with its caldera at the time before the eruption.

The present-day caldera of Santorini with the white Minoan deposit visible as the thick topmost layer in the cliffs.

The Minoan pumice layer in the quarry near Fira.
Discovering the site (Nov 2002)

The caldera cliffs near the site looking north; the Minoan deposit is the thick topmost layer including a 5 m thick base of fall-out pumice. Construction is consuming the pumice layer from top down, and destroying important geological features visible in the wall.

The caldera cliffs near the site looking south.

The first photo of the site: holes in the basal pumice layer, here about 5 meters thick, where the branches of the tree were. The "Science" branch was from the large hole. A piece of wood is lying on the ground...

Other holes left of the one where the "Science" branch was from; they have been covered now (in 2007) by continuing careless building activity.

Near the site is a man-made structure resembling a wall or well; perhaps the spot had a particular significance due to the presence of rare trees, as today, 4000 years ago. (my fieldbook for scale)

Two large, connected holes at the base of the pumce. Deep inside one of them, one could barely see wood, too. This piece was first recovered in July 2007 and brought a wonderful, almost 2 meter long branch back to light, which is now displayed in the new geological museum in Perissa.

The cross section of the branch visible in the large hole at about 2 meters height in the wall; this is the piece that was first recovered and subject of the published investigation.

Walter Friedrich at the site (Feb. 2003)
Recovering the branch of the olive tree (May 2003)
When I talked with archaeologists working at the excavation site of Akrotiri, I met very little interest! I decided to show it to ome of them (who turned out to suffer vertigo at the spot and was only happy to get back alive...). Unfortunately, I was then told that the site was not important enough and besides that, impossible to protect. There was no a comment on the possibility to have not only many kilograms of WOOD, but intact tree rings etc. from the eruption!I informed professor Walter Friedrich who came as soon as he could free himself from teaching and we visited the site again in February 2003. Given the negative reaction from Akrotiri, we agreed it was best to try to recover wood on ourselves to investigate it ourselves.
The opportunity arose when was guiding a group for the tour Fascination Volcano in May 2003. One of the participants was Peter, a Dutch geologist. Peter agreed to help me to try to recover the branch whose cross section one could easily see in the larger hole about 2 meters above ground; it looked as if one might be able to simply pull it out... But how wrong!
It turned out difficult enough: the site was (is) only accessible on a narrow ledge on the steep caldera wall, 200 m above the water, and below a 30 m vertical cliff of pumice and ash, with large blocks in the loose deposit. Bringing a ladder seemed too difficult and risky, so we decided we would try it by standing on each oach other's shoulder. In fact, this worked well. Peter climbed on my shoulder, so his own shoulder was at the height of the hole and he could begin digging away the pumice around the piece of wood, which was falling around me.
Trying to simply pull out the branch didn't work. Peter dug pumice away around the branch as much as he could reach, which took a while. Finally, we realized that the branch was curved and still stuck deep inside, refusing to get loose. We simply had to move the branch itself, even risking to break it and only recover a part. The risk that the site would be destroyed within one season - there's construction of a new hotel going on in the pumice wall above the site.
It took us almost two hours carefully moving the branch up and down, left and right, making it loose slowly from its surroundings, until Peter finally could pull it out: it was around 10 kg heavy, about 1 meter long and 15-20 cm in diameter. In perfect condition, it was only charred on the outside where the bark was still visible, and my greatest fear was it might be used as firewood if someone local got hands of it. However, I had to leave it on the island, for sure.
From Santorini to Heidelberg (2003-04)
I left the branch with friends on Santorini whom I could trust they would not burn it. During the summer months of 2003, Walter managed to built a team of scientists and specialists who were to analyze the wood. The branch thus travelled to Athens, then to Arhus and finally to Heidelberg, where the analysis were made that were eventually published presented in the Science paper. This part of the story is found in numereous places elsewhere.Destruction of the site (ongoing)

Debris of loose deposit is being dumped from the construction site in 20 meter above the site. The first hole where the "Science" branch was recovered is now accessible by foot and will soon be covered.

View inside the hole, were the continuation of the original branch is still visible (now recovered and destined for the museum in Perissa)

Organic remnants of olive leaves in the basal layer of the pumice, proof that the tree was alive at the time of the eruption.

The site and the second branch.

Sample of ash with olive leaves.

The second piece of wood from the same hole after its recovery.

Numerous pottery fragments are found in the Minoan soil near the site

Walter Friedrich on his way from the site