Hidden forces beneath Gibraltar may reshape Atlantic Ocean

The Strait of Gibraltar, the 58-kilometer passage that separates Spain from Morocco and connects the Mediterranean to the Atlantic, may be at the early stages of a geological process that goes far beyond a simple shift in the map. 

A new study used 3D computational simulations to show that the rocks beneath the maritime corridor are triggering a subduction process that could extend into the Atlantic Ocean, as reported by Eco News. However, some eye-catching headlines have recently suggested this change is imminent, whereas the study itself clarifies that the timeline spans roughly the next 20 million years.

Published in the journal Geology, the research was carried out by scientists from the University of Lisbon and the Dom Luiz Institute, together with the Johannes Gutenberg University of Mainz.

The model suggests that a subduction zone formed during the partial closure of the Mediterranean could migrate into the Atlantic—a phenomenon researchers call subduction invasion. If confirmed over geological timescales, the process could lead to a major reshaping of the eastern edge of the ocean, potentially including the formation of a Fire Ring similar to that of the Pacific.

The Strait of Gibraltar lies near a boundary where the African and Eurasian tectonic plates press and slide against each other. This interaction generates stress that can be released through earthquakes.

The study indicates that a dense tectonic plate beneath the Strait of Gibraltar may be slowly sinking into the Earth’s interior, in a process known as subduction.

Subduction occurs when one tectonic plate bends and descends beneath another, moving into deeper layers of the planet. This process can trigger earthquakes, drive volcanic activity, and recycle ancient oceanic crust.

Their simulations are “gravity-driven,” meaning dense slabs can sink and pull the rest of the plate along—similar to a heavy curtain slipping off a table. In practical terms, this helps test whether Gibraltar’s slow subduction could reactivate after a long period of dormancy.

It also connects to the Wilson cycle—the idea that oceans can open, expand, and eventually begin to close. Subduction initiation is critical because it marks the turning point when an ocean stops growing and starts being recycled into the mantle.

So why do some descriptions make it seem like the strait could disappear soon? In geological terms, “soon” can mean tens of millions of years, and this study estimates about 20 million years before Gibraltar’s subduction advances further into the Atlantic.

The researchers describe this shift as “subduction invasion.” Put simply, a subduction zone formed in a closing ocean—like parts of the Mediterranean—may extend into a still-expanding ocean, such as the Atlantic.

There is also an important caveat. The authors emphasize that forming new subduction zones is difficult because oceanic plates are strong and resist bending and breaking, which is why they used models to test what conditions might overcome that resistance.

The Pacific Ring of Fire is a horseshoe-shaped belt about 240,000 kilometers long, known for frequent earthquakes and volcanic activity. The study raises the long-term possibility that a similar system could eventually emerge around parts of the Atlantic.

Still, the article notes that the word “eventually” carries significant weight here. The models describe a new subduction system developing over tens of millions of years—far beyond any human planning timeframe.

By Nazrin Sadigova