The giant ocean between Europe and America will close in 20 million years due to the influence of the subduction zone.
Tectonic plates form the Atlantic Ocean. Image: NOAA
Just before the continents start drifting back together, researchers predict an "Atlantic ring of fire" will form, causing a tectonically active zone to shift from the Mediterranean to the Atlantic. Duong, according to research published in the journal Geology, Newsweek reported on February 16. This will begin to happen in about 2 million years. That is a short time in geological terms but extremely long in human terms.
Tectonic plates often move at extremely slow speeds. Sometimes, oceans are born when tectonic plates move apart and close together when the plates drift back together after hundreds of millions of years, in a process called the Wilson Cycle. It was this process that prompted the supercontinent Pangaea to break up 180 million years ago, forming the Atlantic Ocean, and causing the ancient Tethys ocean to shrink into today's Mediterranean Sea.
For the Atlantic Ocean to close, a new subduction zone needs to form. These are places where one tectonic plate is pushed under another, sinking into the Earth's mantle, occurring due to the density difference between the two plates. Normally, one oceanic tectonic plate will be subducted under another continental or oceanic plate.
Subduction zones are characterized by intense geological activity, including earthquakes, volcanic eruptions and ocean trenches. However, these areas are difficult to form because the tectonic plate is very solid and subduction zones require a tectonic plate to break and bend. However, pre-existing subduction zones can move during a process called transgressive subduction.
According to research using computer models to predict future plate tectonics by the University of Lisbon, the subduction zone in the Mediterranean below the Strait of Gibraltar will move deeper into the Atlantic Ocean in about 20 million years. , creating an Atlantic ring of fire similar to that in the Pacific. João Duarte, a researcher at the University of Lisbon's Dom Luiz Institute, and colleagues describe how the Gibraltar subduction zone has slowed down over the past few million years. Few scientists think it still works. However, after this subduction zone enters the Atlantic Ocean, it will become more active, forcing the Atlantic Ocean to close.
“There are two other subduction zones at either end of the Atlantic Ocean: the Lesser Antilles in the Mediterranean and the Scotia Arc near Antarctica. However, those subduction zones invaded the Atlantic Ocean several million years ago. Studying the Gibraltar zone is an invaluable opportunity because it allows observing the process at an early stage that has just occurred,” Duarte shared.
The team concluded that transgressive subduction zones may be a common way for oceans like the Atlantic to close in, and are therefore an important factor influencing how the planet evolves geologically.
An Khang (Follow Newsweek)
