Ice-age cavern in Saint-Léonard structurally sound, says scientist
A 15,000-year-old underground passage in Saint-Léonard that was discovered in 2017 is structurally sound, according to the scientists who found it.
Luc Le Blanc, one of the cave explorers who discovered the formation dating back to the ice age, says there is no risk of city infrastructure collapsing.
While the cave begins under a park, it extends underneath a developed area.
The passage is connected to Montreal's Saint-Léonard Cavern, which lies underneath Pie-XII Park, not far from Highway 40.
"Geologically, this is very solid," he said. "We have about six metres of rock above the cave ceiling."
The cave was formed thousands of years ago through a process known as glacial tectonism, when a glacier pushes the rock walls apart.
There is still some exploring to do, as part of the cavern is submerged in chilly water. Le Blanc said they are considering pumping out some water to help with their research.
They still want to determine from what direction the glacier entered the cave during the Ice Age.
The main portion of the cavern has been open to members of the public for decades, but tour guides had no idea that a massive section was hidden behind a limestone wall until it was discovered in 2017.
It remains to be seen whether this new section will be open to the public at some point. Le Blanc said they need to determine what the impact would be on the cave's walls.
He suggested a virtual tour, using 360-degree video technology, might be the best option for the protection of both the cave and the public.
