For anyone interested in paleontology, this is almost a la Pales fact: we do not find dinosaur fossils in Quebec because our soil does not contain Mesozoic rock formations, that is – say, the period from 250 to 66 million years before our era during which these reptiles lived. We mostly have older rocks, where glaciers have destroyed the “younger” formations.
Excavations were discovered in the rocky debris of an abandoned iron mine, 20 kilometers from Schefferville, but they destabilized the model. These are not fossilized dinosaurs: the last element discovered and described by Alexander Demers-Botvin, a master’s student at McGill University, is a type of prehistoric mantis. The age of the monster? A hundred million years ago, according to the article he co-published in January in systematic entomology.
dating [de cette formation rocheuse] It is based on a very large number of petrified plant leaves that are there, Alexander Demers-Botvin explains. By comparing with other fossil sites in the world whose age is well known, it was possible to conclude that the formation dates back to a sub-period of the Cretaceous period of 95-100 million years ago. “
Alexander Demers-Botvin published an article describing a type of prehistoric praying mantis. To do this, he relied on a handful of fossils, including this one discovered by Mario Cornuer in 2013. Photo: Mario Cornuer
He got close to the place and never revealed his secrets. In the early 1950s, with the dawning of mining in the area, a geological engineer named Roger A. Blais, who worked at Iron Ore, noticed a thin layer of red rock in the ‘we’re about to do’ area. holes. His eye is attracted to numerous leaf fossils. He picks up some samples and records everything in a report. But excavations are continuing and the geological formation is disappearing under the onslaught of prospectors.
Decades later, in 2018, Alexandre Demers-Botvin appeared on the scene with a few colleagues, including Mario Cornuer, director general of the Montreal Museum of Paleontology and Evolution. They got the fossil winds that were observed at that time. While surveying the rocky remnants, prospectors found fragments of the formation. “These are little bits of rock no bigger than a few centimeters in size,” describes Mario Cornuer. In these pebbles, paleontologists found coniferous spines, leaves, and insect wings… “These elements were deposited at the time at the bottom of a small lake. Conditions were ideal for preservation. The sediments compressed and held together over the ensuing millions of years,” continues Mario Kornoyer. Originally, The lake was probably located at the bottom of a rift, which is low in the earth’s crust.Once the lake dried up, the rift was filled with sediment.Because it was buried deep, the small formation was avoided by the subsequent passage of the glaciers.
Since this unforgettable expedition, Alexander Demers-Botvin has published his descriptions of the extinct insects in scientific articles. “Stick insects, crickets, mayfly nymphs, beetles … there are still many things to know,” declared the young researcher.
If the dinosaurs drank in the small ancient lake, they left no trace there. Mario Cornuer concludes, “Unfortunately, the conditions that permit the preservation of insect cuticles and foliage, especially acidity, do not permit the preservation of bone and wood.”
