The sirenians of the Col des Leques, 40 millions years ago

The Sirenians

The Sirenians of the Col des Lèques existed 40 million years ago. You now know the pass that leads to Castellane from Dignes; the Col des Lèques. Just after the Sirènes campsite on the right (coming from Castellane), a small path begins. It will take you to the site of the Sirens, arranged by the Geological Reserve of Haute Provence. Allow around thirty minutes to walk to discover the region 40 million years ago!

The Sirenians of the Col des Lèques are marine mammals also called sea cows. Indeed, are herbivores that feed on algae and aquatic plants. They mainly live close to odds in warm regions. The fossils present on the site therefore come from a very old relative of the current dugongs and manatees.


A deposit unique in the world

This deposit is one of the oldest and most abundant in the world. Indeed, unlike other Sirenian deposits which generally only have a few ratings, this one is much richer. He was able to highlight skulls, lower jaws, forearms … If the Sirenians were so well preserved, it is because they were buried very quickly. It is undoubtedly a storm or a hurricane which is the cause. The region therefore experienced a tropical climate in the past.

Finally, the Sirenians are buried in yellowish greasy marls and limestones dating back 35 million years. These are based on Jurassic limestones dating back 145 million years! 110 million years separate them and are not represented by any rock?


Site formation

Indeed, after a first phase of erosion, 35 million years ago. The sea returns and the primitive valleys are covered with water. The site is in fact a sort of cove where the mud and sands which once deposited there have become the yellowish rocks of today containing the Sirenians.

One detail remains to be clarified; The site showing fossilized marine mammals is today more than 1000 meters above sea level? Indeed, the uprising of the Alps began more than 30 million years ago little by little elevated in altitude everything that was in its periphery. On this subject, it is interesting to note that the Alps continue to rise by one millimeter per year in certain places.


The Funny Helmets.