TORONTO – A new study has found that an increase in matter under the Earth’s crust under the Atlantic Ocean could push the continents of North and South America further away from Europe and Africa.
Researchers at the University of Southampton have found evidence of a “mantle overflow” from depths of more than 600 kilometers below the mid-Atlantic ridge, increasing the distance between continents.
“There is a growing distance between North America and Europe and it is not driven by political or philosophical differences – it is caused by the convection of the mantle,” one of the study’s scientists, Nick Harmon, said in a press release.
The findings were published Wednesday in the British scientific journal Nature.
According to the study, the tectonic plates attached to America are four centimeters away from those attached to Europe and Africa each year. As the plates move, researchers say new plates are forming to replace them at the center point between regions, known as the Mid-Atlantic ridge.
Researchers have reported that the movement of tectonic plates is usually thought to be driven by gravitational forces or plates sinking back into Earth. However, they say the cause behind the separation of the Atlantic plates has “specifically remained a mystery” because the Atlantic Ocean is not surrounded by “dense, sinking plates”.
The study’s authors conducted two research cruises in 10 weeks and conducted 39 seismometers on the bottom of the Atlantic Ocean. The data collected showed that an overflow of material between the Earth’s crust and its core more than 600 kilometers below the mid-Atlantic ridge could push the bottom plates.
This depth under the mantle is associated with “sudden changes in mineral phases,” according to the study. Researchers say that the ascents below the ridges were usually thought to come from much shallower depths, about 60 kilometers.
“This paper is interesting and rejects the long-standing hypotheses that ridges in the middle of the ocean could play a passive role in plate tectonics. This suggests that in places like the Mid-Atlantic, ridge forces play an important role in driving the new formed separate plates, “said Professor Mike Kendall of the University of Southampton in a statement.
The researchers say the data provides “the first large-scale, high-resolution image of the mantle” beneath the Mid-Atlantic ridge. The researchers said in the study that their findings provide a better understanding of plate tectonics, which can cause natural disasters, including earthquakes, tsunamis and volcanic eruptions.
“The incredible results shed new light on understanding how the Earth’s interior is related to plate tectonics, with hitherto unseen observations,” said lead author Matthew Agius in the statement.
In addition to helping scientists develop better warning systems for natural disasters, chief scientist Kate Rychert said in a statement that plate tectonics also has an impact on sea level and subsequently affects climate change estimates.
“This was completely unexpected. It has broad implications for our understanding of the Earth’s evolution and habitability. It also demonstrates how important it is to gather new data from the oceans. There is much more to explore,” Rychert said.