Unique discovery in the Mediterranean of an 8,000-year-old underwater forest off Palavas

A submerged forest, 8,000 years old, has just been discovered off Palavas and Carnon, thanks to movements of sand and sediment. There are only 2 others in the world. Researchers from the University of Montpellier are trying to understand what our coasts looked like at that time.

septembre 2020. • © F3 LR

At 10 meters deep, off Palavas, on the continental shelf, divers and scientists first thought they had found a wreck. But it is actually a completely different discovery, as fragile as it is exceptional: plant remains. Back at the University of Montpellier, the researchers hasten to protect their treasures. They must quickly be placed away from air, light and heat.

It is a tree stump. It was extracted with its gangue and its roots and remained submerged for around 8,000 years.

Jean-Yves Jouvenel, doctor in biological oceanography

An underwater forest dating from before the Neolithic?

The hypothesis of a forest floor under the sea also seems supported by the collected sediments. These stigmata of an ancient forest are located less than a kilometer from the coast and would still have an area of ​​several hundred square meters.

The objective of the analyses is to date these discoveries more precisely and to determine the nature of the Mesolithic landscape.

The structure of the wood will tell us what species it is. The problem, under sea water, is the waves, the movements of the water which risk causing these strains to leave. There, there is an exceptional state of preservation.

Lucie Chabal, researcher at the Institute of Evolutionary Sciences in Montpellier.

With these analyses, the researchers want to understand what was the environment in which the trees grew. Were they at the edge of a lagoon, near a river? Because at that time, the sea level being lower, at least 10 meters today, we were in a continental environment and not under the sea.

The discovery of this site in France, off Palavas and Mauguio-Carnon, is unique in southern Europe and the Mediterranean. Only 2 other submerged forests have been recorded in the world, one off the American coast of Alabama, in the Gulf of Mexico and one facing the coast of Cornwall, at the southwestern tip of England.

The excavation operation will be renewed next year. The submerged landscapes have not finished revealing their secrets.