Scientists have discovered a crack in the Earth’s crust that threatens to pull North America and Europe closer together and cause the Atlantic Ocean to vanish in about 220 million years.
Researchers at the University of Lisbon have created a new map of the seafloor, off the coast of Iberia – the region of Europe that includes Portugal and Spain – and the results show the beginnings of a new subduction zone.
National Geographic reported on the new data surrounding the subduction zones, and what could happen when the tectonic plates – the large rock slabs that make up the Earth’s crust – crash into one another.
The edge of the heavier plate slides, or subducts, below the lighter plate.
It then melts back into the Earth’s mantle – the layer just below the crust.
The discovery of this new subduction zone, published on June 6 in the journal Geology, could signal the start of an extended cycle that fuses continents together into a single landmass – or ‘supercontinent’ – and closes our oceans.
This breakup and reformation of supercontinents has happened at least three times during Earth’s approximately four-billion-year history.
Speaking with National Geographic, the study’s first author João Duarte said that Earth’s continents could ‘look very much like the Pangea,’ in the far future, referring to a supercontinent that existed about 200 million years ago.
The newly discovered subduction zone is located in the Atlantic Ocean about 120 miles off the southwest coast of Portugal.
It’s composed of six different segments that span a total distance of about 186 miles.
The subduction zone is actually a new crack in the Eurasian plate – one of about a dozen tectonic plates that make up the Earth’s crust.
The Eurasian plate contains all of Europe and most of Asia.
‘In this case, the Eurasia plate is breaking in two,’ Duarte said to National Geographic.
Scientists have long suspected that a new subduction zone was forming near the western margin of the Eurasian plate, off the coast of Portugal.
The region has long been the site of significant earthquake activity, including an 8.7-magnitude quake in 1755 that devastated Lisbon.
This kind of tectonic movement is also at work on the Pacific ‘ring of fire’, located at the borders of the Pacific plate and other major tectonic plates.
The Ring of Fire gets its name because it is composed of over 75 per cent of the world’s active and dormant volcanoes.
It is also the site of the Tohoku earthquke in 2011, and it was the undersea location of plate movement that caused of the devastating tsunami.