Splitting tectonic plate could eventually shrink Atlantic Ocean
Europe and Canada may one day smash into each other if dramatic new research is to be believed.
Scientists say one of Earth’s tectonic plates, the massive shelves of crust that carry the continents and seafloor, is gradually splitting apart off the coast of Portugal.
The rupture may be forming a giant new crack in our planet’s crust, triggering catastrophic earthquakes in the region that may have already claimed 100,000 lives.
Over the next 200 million years, the split could see two new tectonic plates form and slide over one another, helping to pull Europe and North America together into a single “supercontinent.”
Scientists at the University of Lisbon identified the underground split in an area southwest of Portugal.
They were drawn to the region because several unusual quakes have been triggered there in recent centuries.
One of these, the Great Lisbon earthquake of 1755, killed an estimated 100,000 people when it effectively wiped out the Portuguese capital with a huge tsunami.
Centuries later, a smaller rumble and wave were set off in 1969, though fortunately no lives were lost.
Despite a flurry of recent activity, the region of seafloor where these events began is a long way from any active tectonic faults — where earthquakes usually start.
Sitting alongside the Iberian Peninsula, it is extremely flat, a far cry from the mountains and cracks usually seen along Earth’s enormous fault lines.
According to the new study, that’s because the deadly spot on Earth’s Eurasian Plate is hiding a dark secret.
Deep below its flat and seemingly calm surface lie huge cracks and splits that are generating killer earthquakes on the sly.
They formed when damage to the crust allowed water to flood in, creating enormous pressure that is peeling the plate’s top from its bottom.
Geologist Dr. João Duarte, who led the research reckons the new fault is setting off devastating quakes as it tears itself apart.
He says we’re witnessing the birth of a new subduction zone, which is the point at which two plates collide and generate earthquakes.
“It’s a big statement. I think we have something new here,” Duarte told National Geographic.
Scientists know that subduction zones exist, but have spent decades puzzling over how they form.
“It’s one of the biggest unsolved problems in plate tectonics,” Duarte said.
His research finally offers an explanation and may solve a long-standing question over the shifting of Earth’s continents.
Some models of plate tectonics, the movement of Earth’s plates, suggest that Canada and Europe are gradually migrating toward one another.
Duarte believes this could happen in the next 200 million years and his latest work may go some way to explaining how.
As the Atlantic’s plates crack in different spots, new fault lines are created that pull the continents together over time, leaving a trail of mega-quakes in their wake.
They’ll eventually form a single, supercontinent like Pangaea, which split apart billions of years ago to form the continents we know today.
The team’s findings have not been reviewed by other scientists and are based on computer simulations, meaning there’s no guarantee they’re right.
It could be years before experts get a proper look at the cracks, which are buried 150 miles below Earth’s crust.
The findings were presented at the EGU General Assembly 2019 held in Vienna in April.
Source: Read Full Article