Latest news with #AfarTriangle
Yahoo
07-07-2025
- Science
- Yahoo
Pulsing Magma in Earth's Mantle Drives Tectonic Plates Tearing Africa Apart
A spot in eastern Africa called the Afar Triangle marks the meeting point of three rift zones—lines where Earth's crust is being rent apart. Researchers haven't been sure exactly what drives this rifting, but a new study in Nature Geoscience suggests it is caused by rhythmic pulses of molten rock from deep below the surface. Scientists first proposed in the 1970s that a hot upsurge of material from Earth's mantle, known as a plume, was occurring below this spot. Since then researchers have debated whether a single plume, multiple smaller 'plumelets' or something else entirely is pushing the plates apart. Emma Watts, a geochemist at Swansea University in Wales, wanted to settle the question, so she and a team of geophysicists, geochemists and computational scientists put their heads together and came up with a likely answer. 'The more I look into it, the more I see that you've got to have all the pieces of the puzzle to see the big picture,' she says. [Sign up for Today in Science, a free daily newsletter] The team analyzed 130 rock samples from volcanoes in the Afar region. Chemical signatures from each sample helped the scientists piece together the movement of the molten rock below Earth's surface: The researchers calculated the ratios of concentrations of elements such as lead and cerium, which can indicate whether deep mantle material has surged upward, as well as the ratios of different isotopes that each originated from slightly varying reservoirs within the mantle. After comparing their data to computational models of various permutations of mantle plumes, the researchers have found that the best explanation for their observations is a single plume that moves upward in pulses. The pulses appear to exert varying pressure that pushes on each rift zone differently, depending on the way the rift moves and the thickness of the crust on either side. The Afar Triangle's fast-spreading Red Sea Rift has pulses that move farther along the rift zone and that are more frequent than those of the slower-spreading Main Ethiopian Rift in the western part of the triangle. 'The rifting rates are really controlling what we're seeing in the plume,' Watts says. 'What we think is that [the Red Sea Rift is] spreading out faster..., so it has more space to move, and it's being stretched out easier.' The relationship between the mantle movement and the geochemical fingerprints is 'exciting because it suggests geophysics and geochemistry can be married to infer large-scale geodynamic processes,' says Catherine Rychert, a geophysicist at the Woods Hole Oceanographic Institution, who was not involved in this research. This is one of the first known examples of a dynamic mantle plume that responds to the tectonic plates above, so more research is needed to confirm the finding, Rychert says. Watts hopes this technique could be used in other rift systems and that more data from this system could give researchers a more precise view of what is happening deep below Earth's surface.
Yahoo
01-07-2025
- Science
- Yahoo
Earth's Hidden Heartbeat Is Slowly Creating A New Ocean
Deep beneath the surface of Africa, something extraordinary is happening: The Earth's mantle beneath Ethiopia is pulsing like a slow, steady heartbeat. This underground rhythm, though invisible to us, is causing a dramatic geological transformation. It is slowly tearing Africa apart and laying the groundwork for a new ocean. This process is unfolding in the Afar Triangle region of Ethiopia, where the Nubian, Somali, and Arabian tectonic plates meet. This area is part of the East African Rift, a vast crack in the Earth's surface that has been forming for millions of years and pulling those plates away from one another. However, recent research revealed something even more dynamic. Waves of molten rock are rising from deep within the Earth's mantle in periodic, pulsing surges. These pulses are called mantle upwellings. Each pulse pushes magma upward in bursts, weakening the crust above it, resulting in volcanic eruptions and seismic activity. It is impossible to study the exact place where the plates all diverge from each other, but researchers can examine surface volcanic rocks from the Afar region. After looking at samples from 130 young volcanoes in the area, they combined chemical analysis with geological data and modeling. This showed them that the upwelling is not a uniform plume. 'We found that the mantle beneath Afar is not uniform or stationary -- it pulses," explained lead author Emma Watts. As the molten rock from deep within the Earth rises, it pushes the African tectonic plates away from one another. This process will take millions of years, but when the pulses eventually cleave apart the continent, a new ocean basin will form. While this transformation is unfolding on a geologic time scale -- far too slowly to witness during a human lifetime -- it gives scientists a rare chance to study how continents break apart.
Yahoo
30-06-2025
- Science
- Yahoo
Earth's Hidden Heartbeat Is Slowly Creating A New Ocean
Deep beneath the surface of Africa, something extraordinary is happening: The Earth's mantle beneath Ethiopia is pulsing like a slow, steady heartbeat. This underground rhythm, though invisible to us, is causing a dramatic geological transformation. It is slowly tearing Africa apart and laying the groundwork for a new ocean. This process is unfolding in the Afar Triangle region of Ethiopia, where the Nubian, Somali, and Arabian tectonic plates meet. This area is part of the East African Rift, a vast crack in the Earth's surface that has been forming for millions of years and pulling those plates away from one another. However, recent research revealed something even more dynamic. Waves of molten rock are rising from deep within the Earth's mantle in periodic, pulsing surges. These pulses are called mantle upwellings. Each pulse pushes magma upward in bursts, weakening the crust above it, resulting in volcanic eruptions and seismic activity. It is impossible to study the exact place where the plates all diverge from each other, but researchers can examine surface volcanic rocks from the Afar region. After looking at samples from 130 young volcanoes in the area, they combined chemical analysis with geological data and modeling. This showed them that the upwelling is not a uniform plume. 'We found that the mantle beneath Afar is not uniform or stationary -- it pulses," explained lead author Emma Watts. As the molten rock from deep within the Earth rises, it pushes the African tectonic plates away from one another. This process will take millions of years, but when the pulses eventually cleave apart the continent, a new ocean basin will form. While this transformation is unfolding on a geologic time scale -- far too slowly to witness during a human lifetime -- it gives scientists a rare chance to study how continents break apart.
Yahoo
25-06-2025
- Science
- Yahoo
Earth Is Pulsing Beneath Africa Where The Crust Is Being Torn Apart
A deep, rhythmic pulse has been found surging like a heartbeat deep under Africa. At the Afar triple junction under Ethiopia, where three tectonic plates meet, molten magma pounds the planet's crust from below, scientists have discovered. There, the continent is slowly being torn asunder in the early formation stages of a new ocean basin. By sampling the chemical signatures of volcanoes around this region, a team led by geologist Emma Watts of Swansea University in the UK hoped to learn more about this wild process. "We found that the mantle beneath Afar is not uniform or stationary – it pulses, and these pulses carry distinct chemical signatures," says Watts, who was at the University of Southampton in the UK when the research was conducted. "These ascending pulses of partially molten mantle are channeled by the rifting plates above. That's important for how we think about the interaction between Earth's interior and its surface." Related: Our planet's surface is in a constant state of renovation. The tectonic plates into which the planetary crust is divided aren't fixed in position, but shift and collide and even slip underneath one another. The places at which they meet are usually hotspots of geological evolution, quite literally, rampant with volcanic activity that is reshaping the surface from below. The Afar junction is the point at which the Arabian, Nubian, and Somalian plates meet, each departing in their own directions to leave a widening gap under the Afar Triangle. Eventually, the crust will become so thin here that the surface will drop below sea level, creating a new ocean basin off the Red Sea. Scientists suspect that mantle upwelling is playing a role in this continental breakup process, but our understanding of how it works is limited. We can't exactly just dig down to have a close look, so Watts and her colleagues went for the next best thing: looking at material that has been disgorged onto Earth's surface from the mantle by way of volcano. They collected 130 samples of volcanic rock from around the Afar region and the Main Ethiopian Rift, and conducted chemical analyses. They used these analyses combined with existing data to conduct advanced modeling to understand what's going on with the activity under the Triangle. The results showed distinct chemical bands or stripes that repeat across the rift system, delivered by a single, asymmetrical plume of material shaped by its environment and pushing upwards from the mantle. "The chemical striping suggests the plume is pulsing, like a heartbeat," says geologist Tom Gernon of the University of Southampton in the UK. "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." If the team's model is correct, it suggests that mantle plumes and upwellings can be shaped by the dynamics of the tectonic plates above them – a finding that could be used to inform future research into the activity that is continually remodeling our planet. "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," says geophysicist Derek Keir of the University of Southampton and the University of Florence in Italy. "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." The research has been published in Nature Geoscience. Strange Cellular Entity Challenges Very Definition of Life Itself Sharks Do Something Bizarre When Turned Upside Down, And We Don't Know Why Orcas' Strange Beauty Routine Revealed by Scientists For The First Time
