Diamond samples reveal size of lost continentDate: 22 March 2020 Tags: Geography & Environment
Canadian scientists have discovered a fragment of an ancient continent, suggesting that it was 10% larger than previously thought.
They were studying diamond samples from Baffin Island, a glacier-covered land mass near Greenland, when they noticed a remnant of North Atlantic Craton.
The North American Craton stretched from present-day Scotland to North America and broke apart 150m years ago.
Scientists chanced on the latest evidence as they examined exploration samples of kimberlite, a rock that often contains diamonds, from Baffin Island.
The samples were taken from deep below the Chidliak Kimberlite Province in southern Baffin Island. Previous reconstructions of the Earth's plates had been based on shallow rock samples formed at depths of one to 10km.
Kimberlite rocks form very, very deep in the Earth’s crust, similarly to diamonds and are thus a staple of diamond prospectors around the world.
After forming for millions of years at depths of between 150 to 400 kilometers, these rocks are sometimes pushed up to the surface by various geological processes, snatching diamonds along.
Cratons are pieces of continents billions of years old that have remained stable over time and act as the kernel of today’s continents, similar to anchors that today’s landmasses hold on to.
Most cratons have been broken up and moved around by tectonics over time, but some still form the bedrock of modern tectonic plates like the North American plate.
- Knowing where the pieces of these cratons are today allows researchers to understand how they evolved and moved over time, in essence allowing them to map the evolution of our planet’s surface.