In Africa’s eastern region, a massive northeast-south rift is tearing apart, potentially leading to the formation of a new oceanic area in the future. Recently, a British scientific team discovered through research that the giant rift in Africa originates from the pulsation of magma deep within the Earth, a rhythmic pulsation akin to the “heartbeat” of humans.
This finding was made by international teams from institutions like Swansea University and the University of Southampton in the United Kingdom, who uncovered that the massive rift in the Afar region of East Africa stems from rhythmic movements in the mantle. The research results were published in the journal “Nature Geoscience” on June 25.
The Afar region in East Africa is a rare convergence of triple rift valleys on Earth, namely the Ethiopian Rift Valley, the Red Sea Rift, and the Gulf of Aden Rift. These correspond to the Nubian Plate (part of the African Plate), the Arabian Plate, and the Somali Plate respectively. These intersections are hotspots for geological evolution, characterized by frequent volcanic activity and active magma flow beneath.
For a long time, geologists have speculated about the phenomenon of high-temperature upwelling in the mantle, sometimes referred to as mantle plumes, aiding in crustal expansion and the birth of oceanic basins, yet little was known about their structure and behavior. The mantle lies deep within the Earth (approximately 1,000 to 2,800 kilometers), primarily composed of high-temperature solid rock, but overall resembling a viscous fluid.
The research team collected over 130 “young” volcanic rock samples from the Afar and Ethiopian Rift Valley regions. By combining this data with existing geochemical and physical data, they constructed advanced models to analyze the structure of the crust, mantle, and underground magma activity.
The study revealed that the mantle beneath the Afar region is not static but pulsating like a heartbeat, pushing hot material from the deep mantle upwards (upward flow), influencing the structure of the overlying plates (massive solid plates of the crust), resulting in a massive northeast-south rift in East Africa that continues to widen.
The researchers believe that the plates in the rift zone of the Afar region have been continually stretched and thinned over millions of years, making the rift bottom soft like putty. Thinner regions of the Earth’s plates facilitate rapid mantle flow, accelerating the splitting of the Red Sea Rift, possibly leading to the formation of an oceanic basin in the end.
The research team also discovered repetitive chemical patterns within the rift system, influenced by both external environmental factors and a singular, asymmetricly upward rising mantle flow.
They argue that the behavior of the mantle is shaped by plate motions, providing a new perspective for understanding the interaction between the Earth’s interior and surface. If the research model is correct, researchers believe it will offer crucial references for future studies on crustal and plate activities.
The researchers note that the rift is currently expanding at a rate of 5 to 16 millimeters annually, predicting it to complete splitting in millions of years, much faster than previous estimates of tens of millions of years. The Gulf of Aden Rift will gradually widen, ultimately dividing Africa from Yemen in Arabia.
Upon completion of the split, Africa will be composed of two separate continents – a western continent measuring approximately 10 million square miles, including countries like Algeria, Nigeria, Ghana, and Namibia; and an eastern continent of around 1 million square miles, mainly encompassing Kenya, Tanzania, Mozambique, and Ethiopia.
Dr. Emma Watts, the lead author of the study who conducted research at the University of Southampton and now works at Swansea University, expressed to the Southampton University newsroom, “We found that the mantle beneath the Afar region is not still, but pulsating with varying chemical signatures.”
She added, “These pulses are guided by the overlying rift plates, crucial for understanding the interactions between the Earth’s interior and surface.”
Tom Gernon, a professor of Earth Sciences at the University of Southampton and a co-author of the study, says, “Chemical patterns indicate that the mantle is pulsating like a heartbeat. These rhythmic pulses appear related to plate thickness and stretching rates. For example, the Red Sea Rift expands faster, showing more efficient and regular pulsations, similar to blood flowing through a narrow artery.”
Dr. Derek Keir, an associate professor of Earth Sciences at the University of Southampton and the University of Florence and a co-author of the study, stated, “We found that the evolution of deep mantle upwelling is closely tied to the movements of overlying plates. This has profound implications for how we interpret surface volcanic activity, seismic events, and the continental splitting process.”
Keir added, “This research demonstrates that deep mantle upwelling can flow at the base of plates and help concentrate volcanic activity in the thinnest parts of the plates. In the future, we will focus our research on mantle flow patterns and rates.”