A new study warns that a gigantic subduction zone may soon consume the Atlantic Ocean, and it is being called the “Ring of Fire.”
According to Portuguese geologists, the subduction zone is beneath the Gibraltar Strait, a tiny body of water connecting Spain and Morocco. However, researchers believe it has the potential to extend and grow into the Atlantic, eventually causing the ocean basin to “close” or shrink. This will occur in approximately 20 million years.
João Duarte, a professor of tectonics at the University of Lisbon in Portugal, conducted the recent study. He and his colleagues warn that entire oceans could close if new “subduction zones” arise; the Atlantic may already be experiencing this phenomenon.
“We have good reason to think that the Atlantic is starting to close,” Professor Duarte told MailOnline. “Subduction zones cause the oceans to close by pulling their ocean floor back into the mantle, bringing the continents together.”
The Eurasian and African Plates are the two primary tectonic plates that meet at the 10-mile Gibraltar Strait, which divides Spain and Morocco, as well as Europe and Africa.
Earthquakes may occur in this subduction zone because the African plate is subducting beneath the Eurasian plate. As the subduction zone under the Gibraltar Strait is dormant, the plate is slowly sinking into the Earth’s mantle.
According to Professor Duarte and associates, subduction zones have the capacity to expand and penetrate into adjacent oceanic regions, a phenomenon known as subduction invasion.
One of the world’s most minor subduction zones, beneath the Gibraltar Strait, is currently only 125 miles long despite plunging to around 350 miles. However, according to Professor Duarte, after 20 million years, it might stretch to a distance of roughly 500 miles.
For the study, the researchers used computer modeling to simulate the subduction zone’s life from its development during the Oligocene epoch, which occurred between 34 million and 23 million years ago. They discovered that, within the next 20 million years, it would travel west across the narrow Gibraltar Strait. According to the model, the extended subduction zone will create a new Atlantic subduction system known as the Ring of Fire.
As the ocean basin shrinks, subduction progressively presses the ocean floor underneath, drawing continents closer together. Consequently, the Atlantic might eventually shut up due to this new Ring of Fire, albeit it would take an estimated 20 million years to evaporate.
The team says in their study, published in the journal Geology, “The results suggest that the arc will propagate farther into the Atlantic after a period of quiescence.” The models also show how a subduction zone starting in a closing ocean can migrate into a new opening ocean through a narrow oceanic corridor.
Subduction invasion is a frequent method of subduction initiation in oceans similar to the Atlantic. It also represents a significant stage in Earth’s recent geological evolution. The fact that the Gibraltar subduction is still active significantly affects the region’s seismic activity.
The Great Lisbon Earthquake of 1755 and other such incidents are a constant reminder of the seismic threat and the importance of being “prepared.” With an estimated magnitude of 7.7, the historic disaster claimed over 12,000 lives and almost wholly destroyed Lisbon and its surroundings.
