Scientists find Earth’s mantle beating like a heart, slowly tearing Africa apart

The study focuses on the Afar region in Ethiopia—a unique zone where three tectonic plates meet. Researchers found that this area sits above a plume of hot mantle that rises and falls like a beating heart. This upwelling mantle is not constant, but pulses upwards, reshaping how scientists understand the relationship between Earth’s deep interior and surface features.

“We found that the mantle beneath Afar is not uniform or stationary – it pulses, and these pulses carry distinct chemical signatures. These ascending pulses of partially molten mantle are channelled by the rifting plates above. That’s important for how we think about the interaction between Earth’s interior and its surface,” said Dr. Emma Watts, lead author of the study.

The international research project brought together geologists and geophysicists from ten institutions.

A rare view beneath the crust in Africa

The Afar region is one of the only places on Earth where scientists can directly observe the meeting point of three massive tectonic rifts: the Main Ethiopian Rift, the Red Sea Rift, and the Gulf of Aden Rift. These rift zones are areas where the Earth’s crust is pulling apart—ultimately creating space for a new ocean basin to form.

Scientists have long believed that a hot plume of mantle lies beneath Afar in Africa, pushing upwards and weakening the crust above. But until now, very little was known about its behavior or structure.

To dig deeper, the team collected more than 130 volcanic rock samples from across the Afar and Main Ethiopian Rift regions. Using this new data alongside existing geochemical records and advanced statistical modeling, they pieced together a clearer view of the mantle beneath.

Their analysis revealed a single, asymmetric mantle plume located beneath the region in Africa. This plume shows repeated chemical bands—what the researchers describe as “geological barcodes.” These bands vary depending on the conditions in each of the three rift arms, revealing how the plume reacts to the stretching and thinning of the overlying tectonic plates.

“The chemical striping suggests the plume is pulsing, like a heartbeat,” explained Professor Tom Gernon of the University of Southampton, a co-author on the study. “These pulses appear to behave differently depending on the thickness of the plate, and how fast it’s pulling apart. In faster-spreading rifts like the Red Sea, the pulses travel more efficiently and regularly like a pulse through a narrow artery.”

Links to earthquakes, volcanoes, and ocean birth

This new view into Earth’s interior doesn’t just change how we think about mantle plumes. It also connects deep processes to visible surface activity such as earthquakes, volcanic eruptions, and the breakup of continents.

“We have found that the evolution of deep mantle upwellings is intimately tied to the motion of the plates above,” said Dr. Derek Keir, Associate Professor in Earth Science at both the University of Southampton and the University of Florence. “This has profound implications for how we interpret surface volcanism, earthquake activity, and the process of continental breakup.”

Keir added that these mantle surges may help focus volcanic activity in areas where the crust is thinnest. “The work shows that deep mantle upwellings can flow beneath the base of tectonic plates and help to focus volcanic activity to where the tectonic plate is thinnest. Follow-on research includes understanding how and at what rate mantle flow occurs beneath plates.”

Watts emphasized the importance of working across disciplines to solve these geological puzzles. “Working with researchers with different expertise across institutions, as we did for this project, is essential to unravelling the processes that happen under Earth’s surface and relate it to recent volcanism. Without using a variety of techniques, it is hard to see the full picture, like putting a puzzle together when you don’t have all the pieces.”

The study was recently published in the journal Nature Geoscience.