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Electrifying Petrified Wood Discovery on the Island of Lesbos, Greece

Petrified Wood Trunk on the Island of Lesbos

The Greek island of Lesbos is notable for it’s Petrifed Wood forest, a protected national monument. The forest is located on the western portion of the island and was formed from the Late Oligocene to Lower–Middle Miocene and consists of  silicified remnants of a sub-tropical forest that going back 20–15 million years ago.

Recent discoveries in the rich Petrified Forest have been electrifying. First was the rare discovery of a spectacular 19.5 meter long log , with accompanying roots, branches, and trees, the only found to date in over 25 years of excavations. Weeks later, the excavators uncovered over 150 more petrified wood logs and petrified wood stumps including conifers, fruit producing trees, sequoia trees, pine, palm, cinnamon and oak trees. The finds were all discovered in the same pit.

The excavation team has been working since 2013 excavating along a 20km stretch of highway and have made 15 major finds, but these all pale to this most recent discovery, which was actually the result of a lucky accident. One the excavators notices a leaf in a stretch of the highway about to get asphalted, and halted the road work.

The park has been designated a UNESCO Global GeoPark. There is an excellent museum well worth visiting. If you visit the park, remember that the removal and transfer of fossilized material is prohibited by law. The forest includes six parks. The fossilized trees include mainly huge sequoias and primitive pine trees in an ecosystem closest to the coniferous forests of North America.

While we haven’t been to Lesbos we do have some of our own spectacular Petrified Wood finds available for sale in our catalog.

Top image is of Petrified Forest on the Island of Lesbos, Greece, by C messier – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=8926168

Petrified Wood near Sigri, Island of Lesbos, Greece. Photo By Rutger2 at nl.wikipedia, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=3222318

Petrified Wood, Island of Lesbos, Greece. Photo by Signy – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=11642494

Unstable temperature and relative humidity, different rates of expansion and contraction, salt movement, living plant roots and other factors cause cracking in fossil wood. In order to prevent dirt and contemporary vegetation from accumulating into the cracks, and prevent breakages, solutions of especially prepared consolidants are injected in surface cracks. [Kyriazi, E. and Zouros, N. (2008) ‘Conserving the Lesvos Petrified Forest’, Studies in Conservation 53 (Supplement-1 – Conservation and Access: Contributions to the 2008 IIC Congress), London, p. 141-145] The beautiful rose colours of the silicified fossil wood in this picture are due to the presence of manganese ions. Photo by E.Kyriazi – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=44800562

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Short Crystal: Quartz and the Fossilized Bird

Photograph of the holotype of Zhouornis hani, a type of Enantiornithes

A recent study in Frontiers in Earth Science reveals that researchers discovered quartz crystals in the stomach of a bird that lived alongside the dinosaurs. The bird, a member of the Enantiornithes clade of fossil birds, appeared to be a sensational discovery, as previously there had never been a find which preserved any traces of food in the fossils stomach which would clue researchers in to the diet of the animal. Many modern birds have what’s called a gizzard, a thick and muscular portion of the stomach used to help digest food. Often birds swallow small stones know as gizzard stones, which make their way to the gizzard itself where it helps to crush tough or difficult to digest food. These stones are know as gastroliths and have been found in some dino and bird fossils providing hints as to the diet of those animals. The presense of stones in the stomach, though isn’t defiinitive as to the purpose of the stones. There are some modern birtds of prey that swallow rocks to help move material through their digestive tract, cleaning it out, and it’s hard to differentiate between a gastrolith and a gastrolith that is a gizzard stone without knowing anything about the diet and habits of the animal using the stone. In the end, the reesearchers determined that the quart material found where the birds stomach would have been probably was a gastrolight at all. After exposing the supposed gastroliths to X-rays and a scanning electron microscope it was determined that the rocks were actually chalcedony crystals, quartz that grew in sedimentary rocks. There is evidence of chalcedony crystals forming with a clamshell, or replacing minerals in fossil bones. Furthermore, the crystals in this case were all connected in a thin sheet rather than separate rocks. The rocks were also much larger than would be expected of rocks swallowed by a bird that size. In the end there just wasn’t enough evidence, and some negative evidence against the idea that the rocks were in the birds stomach. Just goes to show, never count your gastroliths before they’s been swallowed.

We don’t have any examples of Enantiornithes, but you can check our our collection of fossils for sale here.

Top image is a photograph of the holotype of Zhouornis hani, a type of Enantiornithes,
By Yuguang Zhang, Jingmai O’Connor, Liu Di, Meng Qingjin, Trond Sigurdsen, Luis M. Chiappe​ – https://peerj.com/articles/407/, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=33060650