Major tectonic discovery beneath the Lesser Antilles 🌍

Scientists have discovered an unusually thick mantle transition zone beneath the Lesser Antilles. This discovery sheds new light on how oceanic plates sink into the Earth's mantle.

Variations in rock composition within oceanic plates influence their trajectory and subduction speed. These differences, inherited from ancient tectonic processes, play a key role in the dynamics of the Earth's mantle.


The mantle transition zone, located between 255 and 410 miles (410-660 km) deep, acts as a regulator for material movement toward Earth's depths. The presence of basalts in this zone can slow or even stop the descent of subducting plates.

An international team has identified an exceptionally thick mantle transition zone beneath the Lesser Antilles. This thickness, reaching about 205 miles (330 km), is explained by a basalt-rich composition, revealing the importance of inherited materials in subduction.

These findings, published in Nature, enhance our understanding of how surface materials are recycled into Earth's depths. This process is essential for maintaining our planet's climate and habitability over geological timescales.

The VoiLA project, responsible for these discoveries, deployed 34 seismometers on the ocean floor. This initiative marks a first in the study of Atlantic subduction zones.

Researchers emphasize that tectonic plates retain a 'memory' of their history, influencing mantle convection. This discovery opens new perspectives on material mixing within Earth.

What is the mantle transition zone?

The mantle transition zone is a layer located between 255 and 410 miles (410-660 km) deep. It plays a crucial role in material circulation between Earth's surface and its depths.

This zone is characterized by mineral phase changes that affect rock density and viscosity. These transformations influence tectonic plate dynamics and mantle convection.

The discovery of an unusually thick transition zone beneath the Lesser Antilles suggests a unique, basalt-rich composition. This composition might slow oceanic plate subduction, changing our understanding of Earth's dynamics.

How do tectonic plates influence the mantle?

Tectonic plates transport surface materials into the mantle's depths during subduction. This process recycles volatile elements and minerals, playing a key role in Earth's evolution.

Plate composition, particularly basalt content, affects their behavior during subduction. Basalt-rich zones can slow or block plate descent into the mantle.

This study reveals that plates retain a 'memory' of their geological history. This memory influences mantle convection and material mixing, essential for maintaining Earth's habitability.