Footprints from sauropod dinosaurs, giant herbivores with long necks, were found in Plagne, near Lyon, France.

The dinosaur footprints in Plagne are circular depressions surrounded by a fold of limestone sediment. These depressions are very large, up to 1.50 metre in total diameter, suggesting that the animals were larger than 40 tonnes and 25 metres in length.

Discovered by Marie-Hne Marcaud and Patrice Landry, the dinosaur footprints have been authenticated by Jean-Michel Mazin and Pierre Hantzpergue, both of the Palnvironnements et Paliosphs laboratory (CNRS/Universitlaude Bernard Lyon 1).

According to the researchers’ initial analyses, these dinosaur footprints are the largest found to date. Furthermore, the tracks spread over dozens and possibly even hundreds of metres.

More significant digs will be conducted over the next few years and could result in the Plagne site being one of the largest known dinosaur sites on earth.

Marcaud, Patrice Landry and other members of the Soci des naturalistes d’Oyonnax (SDNO) have been searching for dinosaur footprints for years.

Convinced that the region had a rich paleontological heritage, they focused on potential sites and have been exploring them systematically. The SDNO is thus responsible for a number of discoveries.

It was during one of these outings, on April 5, 2009, that Marcaud and Landry discovered the extraordinary footprints at Plagne, says a CNRS release.

They contacted Jean-Michel Mazin and Pierre Hantzpergue, of CNRS/Universitlaude Bernard Lyon 1. Researchers authenticated the footprints based on morphological criteria and the sediment containing them. They believe that the Plagne site was along a route used by sauropod dinosaurs.

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