A 3-D Look Beneath the Mediterranean: How the Mantle Moves and What It Reveals
Last modified: November 28, 2025 | First published: November 28, 2025
Summary
The Mediterranean is one of the most geologically complex regions on Earth. Colliding plates, subduction zones, volcanic activity, and mountain building have shaped it over millions of years. To understand what’s happening deep below the surface, we created the first 3-D model of the entire region that shows not only how fast seismic waves travel, but also the directions they prefer to move. This lets us “see” how mantle rocks flow and deform. Our model confirms large portions of sinking lithosphere, called slabs, and reveals where these slabs break, detach, or create “windows” in the mantle. These insights help reconstruct the Mediterranean’s geological history and show that the mantle is still actively moving today.
How We Did It
We can’t dig into the Earth, but we can use seismic waves, vibrations from earthquakes, to explore its interior. Waves change speed and direction as they pass through different rocks—similar to how light bends passing from air into water.
In this study, we combined two types of seismic data:
- P-wave travel times – showing how fast waves move. Faster waves indicate cooler, denser rocks, like sinking slabs. Slower waves mark hotter or more deformed areas.
- SKS splitting intensity – revealing seismic anisotropy, which shows preferred wave directions. This tells us how crystals in mantle rocks are aligned, reflecting mantle flow.
By combining these datasets in a single analysis, we created a clear and physically consistent 3-D image of the Mediterranean mantle.
What We Found
Western Mediterranean: a mosaic of sinking slabs
Three major slabs lie beneath this region:
- Alboran
- Apennine
- Alpine
Parts of these structures formed as subduction zones retreated over the past ~30 million years, while others reflect older tectonic events. All of them appear as fast-velocity zones, showing cold, dense material sinking deep into the mantle.
Eastern Mediterranean: active and complex tectonics
Here, three main slabs dominate:
- Dinaric
- Carpathian
- Hellenic
Seismic waves show that the Adria microplate is still moving northeast, meaning tectonic activity continues to shape the mantle today. In Greece and Cyprus, mantle structures change rapidly from place to place. This suggests that parts of the sinking plates are breaking, bending, or shifting sideways, which influences mantle flow below.
Slab windows and volcanism
Where slabs have broken or moved aside, they leave slab windows, openings that allow mantle material to rise more easily. These areas often match recent or active volcanic regions, linking deep mantle structures with surface activity.
Horizontal and vertical mantle flow
Our model shows two main types of mantle movement:
- Horizontal flow, where mantle rocks move sideways
- Vertical flow, where material rises or sinks
These patterns help us understand how the Mediterranean mantle has deformed over time and continues to move today.
Why It Matters
This is the first complete 3-D seismic model of the Mediterranean that shows not just where the mantle is, but also how it flows and deforms.
Understanding these deep structures helps scientists:
- See where plates are stable or breaking apart, which relates to earthquake and volcanic risks
- Identify the most active parts of the mantle, revealing how the Earth’s interior shapes mountains, seas, and surface landscapes
In short, this research improves our understanding of the Earth’s inner workings and explains the natural processes shaping the Mediterranean region today.
Original Publication:
Rappisi, F., Lo Bue, R., Vanderbeek, B. P., Confal, J. M., Erman, C., Baccheschi, P., … & Faccenda, M. (2025). 3‐D mantle flow and structure of the Mediterranean from combined P‐wave and splitting intensity anisotropic tomography. Journal of Geophysical Research: Solid Earth, 130(6), e2024JB030883. https://doi.org/10.1029/2024JB030883
