Hints of ancient ‘lost continent’ found in Baffin Island, Canada during diamond exploration

Hints of ancient ‘lost continent’ found in Baffin Island, Canada during diamond exploration

Inukshuk on Baffin Island, Nunavut, Canada. University of British Columbia geologists studying samples of the mineral kimberlite for diamond exploration found instead evidence of an ancient, lost continent, or craton, that broke up about 150 million years ago.(Getty Images/iStock)

Fragments of an ancient continent that used to stretch from Scotland to Greenland have been found under Baffin Island, Canada, indicating that the lost land mass was even bigger than scientists initially thought.

Researchers exploring diamond deposits in the Canadian territory of Nunavut, comprising Inuit traditional territory, found unique mineral compositions hitching a ride on the deposits they were bringing up. The findings indicate the once-upon-a-time continent was 10% larger than previous estimates, CNN reported.

The University of British Columbia (UBC) geologists were studying diamond samples brought up from deep beneath the surface. This fragment of Earth’s crust is known as the North Atlantic Craton, which ran from Scotland to North America and broke up 150 million years ago, CNN said.

A craton is “a part of the Earth's crust that has attained stability, and has been little deformed for a prolonged period,” the U.S. Geological Survey (USGS) explains.

University of British Columbia geologists said they did not expect to find evidence of the continent, or craton, all the way over in Canada. They were studying rock samples of kimberlite, which were formed millions of years ago, 93 miles to 250 miles below Earth’s surface. They are driven up to the surface by geological and chemical forces, the UBC researchers said in a statement, and these igneous rocks occasionally come carrying diamonds embedded within them. For this reason, studying kimberlite is a major part of diamond exploration work.

“For researchers, kimberlites are subterranean rockets that pick up passengers on their way to the surface,” explained University of British Columbia geologist Maya Kopylova in a statement. “The passengers are solid chunks of wall rocks that carry a wealth of details on conditions far beneath the surface of our planet over time.”

This time what was embedded in the kimberlite being studied was arguably more valuable – at least from a scientific standpoint. Working at the De Beers Chidliak Kimberlite Province property in southern Baffin Island, the geologists were astonished to find a unique mineral signature.

“The mineral composition of other portions of the North Atlantic craton is so unique there was no mistaking it,” said Kopylova, the lead author of the paper her team published about the findings in the Journal of Petrology. “It was easy to tie the pieces together. Adjacent ancient cratons in Northern Canada—in Northern Quebec, Northern Ontario and in Nunavut—have completely different mineralogies.”

The new discovery is a puzzle piece of sorts that shines a light into Earth’s past.

“Finding these ‘lost’ pieces is like finding a missing piece of a puzzle,” Kopylova said. “The scientific puzzle of the ancient Earth can’t be complete without all of the pieces.”

Until now, samples bearing these clues came from much closer to Earth’s surface, the researchers said.

“With these samples we’re able to reconstruct the shapes of ancient continents based on deeper, mantle rocks,” Kopylova said. “We can now understand and map not only the uppermost skinny layer of Earth that makes up one percent of the planet’s volume, but our knowledge is literally and symbolically deeper.”

MMW