The Atlantic Ocean emerged around 180 million years ago as the Pangea supercontinent split, and it is anticipated to close eventually.
A new study has detailed how the Atlantic Ocean will ultimately close.
Ocean closure is a complicated process, with subduction zones emerging as a significant mechanism for slowing ocean development and commencing closure. These are areas where one tectonic plate shifts beneath another.
Use of Computational Models Using advanced computational models, the researchers from the University of Lisbon forecasted the evolution of a subduction zone beneath the Gibraltar Strait.
This subduction zone is expected to extend deeper into the Atlantic Ocean, playing a crucial role in forming what geologists call an “Atlantic ring of fire,” or Atlantic subduction system.
In geological terms, this transformative event is expected to occur relatively “soon,” i.e., in the next 20 million years.
“There are two other subduction zones on the other side of the Atlantic – the Lesser Antilles, in the Caribbean, and the Scotia Arc, near Antarctica. However, these subduction zones invaded the Atlantic several million years ago. Studying Gibraltar is an invaluable opportunity because it allows observing the process in its early stages when it is just happening”, said João Duarte, the study’s first author.
Subduction Invasion Subduction zones pose a challenge as they require the breaking and bending of tectonic plates, which are intrinsically powerful.
The study introduces the concept of “subduction invasion,” where existing subduction zones from declining oceans migrate into new, untouched oceans.
The computational, gravity-driven 3D model reveals previously unknown insights into how this direct invasion process occurs.
“Subduction invasion is inherently a three-dimensional process that requires advanced modelling tools and supercomputers that were not available a few years ago. We can now simulate the formation of the Gibraltar Arc with great detail and also how it may evolve in the deep future” explained João Duarte.
As per the press release, this research demonstrates that subduction invasion is likely a widespread mechanism initiating subduction in Atlantic-type oceans, contributing significantly to the geological evolution of our planet.
The discovery of continuous activity in the Gibraltar subduction zone has significant consequences, notably for seismic occurrences in the region. Subduction zones, known for creating the most violent earthquakes on Earth, represent a huge hazard, highlighting the importance of preparedness.
