Scientists Detect Deep Earth Pulses Beneath Africa

Deep beneath Africa, the Earth’s heart is beating.

Researchers have discovered rhythmic surges of molten rock pulsing upward from the planet’s interior, gradually tearing the continent apart and forming what will eventually become a new ocean. The discovery reveals that these mantle plumes behave like a geological heartbeat, carrying distinct chemical signatures as they rise toward the surface.

The study, published in Nature Geoscience, focused on Ethiopia’s Afar region—a rare place where three massive tectonic rifts converge. Using advanced statistical modeling and over 130 volcanic rock samples, scientists mapped the structure of a single, asymmetric plume that pulses beneath the rifts like blood flowing through arteries of varying sizes.

Geological Barcodes in the Earth

The research team discovered that the mantle plume creates distinct chemical bands that repeat across the rift system—geological barcodes that tell the story of deep Earth processes. These patterns vary in spacing depending on local tectonic conditions, providing unprecedented insight into how Earth’s interior communicates with its surface.

“We found that the mantle beneath Afar is not uniform or stationary – it pulses, and these pulses carry distinct chemical signatures,” explained lead author Dr. Emma Watts, who conducted the research at the University of Southampton. “These ascending pulses of partially molten mantle are channelled by the rifting plates above.”

The pulses behave differently based on the thickness and spreading rate of overlying tectonic plates. In faster-spreading rifts like the Red Sea, the pulses travel more efficiently and regularly, similar to blood flowing through a narrow artery.

Three Rifts, One Source

The Afar region presents a unique natural laboratory where three major rifts meet:

• Red Sea Rift: Spreading at 10.5-19.5 millimeters per year
• Gulf of Aden Rift: The oldest, beginning about 35 million years ago
• Main Ethiopian Rift: The youngest, starting 11 million years ago, spreading at ~5.2 millimeters per year
• Crustal thickness: Varies from 16 kilometers in the Red Sea to 33 kilometers in the Ethiopian rift

Despite their different characteristics, all three rifts show evidence of being fed by the same underlying mantle upwelling. The team’s statistical analysis of 14 key geochemical and geophysical variables confirmed that a single, chemically heterogeneous plume best explains the observed patterns.

A Beating Heart Deep Below

Professor Tom Gernon of the University of Southampton, a co-author of the study, emphasized the dynamic nature of these deep processes: “The chemical striping suggests the plume is pulsing, like a heartbeat. These pulses appear to behave differently depending on the thickness of the plate, and how fast it’s pulling apart.”

The research reveals how the overlying tectonic plates actually influence the behavior of deep mantle upwellings. Thicker, slower-spreading plates create a “bottleneck” effect that compresses the spatial pattern of chemical heterogeneities, while thinner, faster-spreading plates allow more efficient flow.

Advanced statistical modeling using principal component analysis and K-means clustering revealed that the same chemical signatures appear in different rift arms, indicating shared pulses from the same deep source—evidence of the mantle’s rhythmic behavior.

Implications for Understanding Earth

This discovery challenges previous assumptions about how Earth’s interior works. Rather than static, uniform upwellings, the research shows dynamic, responsive systems that interact intimately with surface tectonic processes.

Co-author Dr. Derek Keir noted the broader significance: “We have found that the evolution of deep mantle upwellings is intimately tied to the motion of the plates above. This has profound implications for how we interpret surface volcanism, earthquake activity, and the process of continental breakup.”

The work involved international collaboration among 10 institutions, combining expertise from the University of Southampton, Swansea University, universities in Italy and Germany, and research centers in Ireland and Ethiopia.

Future Ocean Formation

Over millions of years, these pulsing upwellings are literally pulling Africa apart. As tectonic plates stretch and thin like soft plasticine, they eventually rupture—marking the birth of a new ocean basin. The Afar region represents this process in action, offering scientists a window into how new oceans form.

The research also provides insights into volcanic activity and earthquake patterns, since the mantle flow helps focus volcanic activity where tectonic plates are thinnest. Understanding these deep processes could improve predictions of geological hazards in regions undergoing continental breakup.

As Dr. Watts concluded, this work demonstrates that “putting together the full picture” requires collaboration across disciplines and institutions, combining different techniques to understand the complex processes occurring beneath our feet.