Growing up, most of us learned that the Earth is home to seven continents.
But it may be time to rewrite the geography textbooks, as a controversial study now claims there are actually only six continents.
Researchers at the University of Derby say the breakup of the European and North American continents is still ongoing.
Dr Jordan Phethean, author of the study, said: ‘The discovery indicates that the North American and Eurasian tectonic plates have not actually yet separated, as traditionally believed to have happened 52 million years ago.
“In fact, they are still stretching and breaking.”
Growing up, most of us learned that Earth is home to seven continents. But perhaps it’s time to rewrite the geography textbooks, as a controversial study claims there are actually only six continents.
The new study focused on the formation of Iceland, which lies between the Greenland Sea and the North Atlantic Ocean.
The new study focused on the formation of Iceland, which is located between the Greenland Sea and the North Atlantic Ocean.
Until now, it was widely believed that Iceland formed about 60 million years ago when the Mid-Atlantic Ridge (the boundary between the North American and Eurasian tectonic plates) began to give way, creating a plume of hot mantle that gave rise to a volcanic island.
However, in their new study, the team challenged this theory.
By analysing the movement of tectonic plates in Africa, researchers now suggest that Iceland and the Greenland-Iceland-Faroes Ridge (GIFR) also contain pieces of lost and submerged fragments of the European and North American continents.
They call this newly recognized feature a “fractured oceanic magmatic plateau,” or ROMP.
“I like to think of this concept as the Earth Science equivalent of finding the Lost City of Atlantis: fragments of a lost continent submerged beneath the sea and miles of thin lava flows,” Dr Phethean explained.
‘By studying the evolution of rifting in the Afra volcanic region in Africa and comparing it to the behaviour of the Earth in Iceland, we can see that these two regions are evolving in very similar ways.’
Until now, it was widely believed that Iceland formed about 60 million years ago when the Mid-Atlantic Ridge (the boundary between the North American and Eurasian tectonic plates) began to give way, creating a plume of hot mantle that gave rise to a volcanic island.
If the researchers are correct, this means that the disintegration of the European and North American continents is still continuing.
Scientifically speaking, this would mean that North America and Europe could be classified as one continent, not two.
“While it is controversial to suggest that GIFR contains a large amount of continental crust within it, and that the European and North American tectonic plates may not have yet officially separated, our findings suggest this is the case,” Dr Phethean added.
The findings are still conceptual, but researchers now plan to explore Iceland’s volcanic rocks for more concrete evidence of ancient continental crust.
They are also conducting plate tectonic models of the region and will use computer simulations to try to model the ROMP formation.
The news comes shortly after Dr Phethean was part of a research team that discovered a new “protomicrocontinent” hidden between Canada and Greenland, thought to have formed 60 million years ago.
The protomicrocontinent is 400 kilometers long (about the same size as England) and currently lies beneath the Davis Strait, which connects the Labrador Sea in the south to Baffin Bay in the north.
“Rifting and microcontinent formation is an ongoing phenomenon,” Dr Phethean said.
‘The discovery of the Davis Straight protomicrocontinent allows us to better understand the process by which microcontinents form, which in turn tells us more about how plate tectonics works on Earth.
‘This may allow scientists to better predict where useful resources might be found, what the Earth might look like millions of years from now, and how plate tectonics worked in Earth’s early history, as well as the role it might have played in the development of life.’