A long-hidden plume of magma beneath Oman’s Salma Plateau may have played a surprising role in shaping the Indian subcontinent’s ancient journey, researchers report. This “ghost” plume — hot material trapped beneath Earth’s thick crust — cannot erupt but may have shifted the Indian tectonic plate’s course during its dramatic collision with Eurasia tens of millions of years ago. First detailed in the journal Earth and Planetary Science Letters, the finding reveals a new class of deep mantle plumes that shape continents silently, without the typical signature of surface volcanoes.
Hidden ‘Ghost’ Plume Beneath Oman May Have Steered India’s Collision Path with Eurasia
As per a Live Science report, the plume was detected using seismic data from Oman’s dense sensor network. Under the leadership of geophysicist Simone Pilia, the group discovered that the plume altered the way sound waves moved through Earth’s layers, which in turn pointed to its presence. Unlike most mantle plumes, which rise and erupt through the oceanic plates, Dani is amagmatic and does not create surface eruptions because of the thick continental crust above the plume. This finding means that there may potentially be many hidden plumes lurking beneath continents.
The Dani plume is the first such non-eruptive plume beneath a continental plate, which is broadening scientists’ view of how mantle dynamics unfold out of sight. The researchers also calculated the movement of the Indian plate and found that it took a significant turn between 40 and 25 million years ago, which might have been affected by the shear stress created by the plume. The plume’s effects on topography are expected to be small regionally, but its geological role could be relatively large.
While plumes typically leave a visible volcanic trail—like Hawaii’s island chain—the Dani plume’s evidence may have been erased by subduction activity in the nearby Makran zone. Still, researchers say this finding opens the door to discovering more “ghost” plumes, particularly in regions with similar thick crusts, such as Africa. As seismic technologies advance, more silent subterranean forces shaping Earth’s history may come to light.
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![Scientists Found a Continent-Sized Geological Structure Hiding Beneath Antarctica
The East Antarctic Ice Sheet is almost unfathomably huge. Covering about 75% of the entire frigid continent (nearly everything on its side of the Transantarctic Mountains), the sheet covers about 3.9 million square miles (10.2 million square kilometers) and extends down 1.4 miles (2.2 km), on average, before coming into contact with Earth’s surface. At its deepest, the ice plunges down over 3 miles (4.9 km). For decades, scientists assumed that this literally continent-sized block of ice rested on an expansive and stable chunk of Earth’s crust known as a craton. A team of researchers has now complicated that picture—mapping a vast, interconnected geological structure that fans out from a troubling “tectonic deformation.” Beneath this ice sheet, thinner and more geologically recent slices of crusty lithosphere fan out into hidden valleys called “pull-apart basins.” These basins—30 elongated wedge-shaped valleys in total—constitute an entirely new, continental-scale geological region underneath Antarctica, in fact, one which the researchers have named the East Antarctic Fan-Shaped Basin Province (EAFBP). But it’s how they likely formed that has now caught researchers’ attention.
To put it bluntly, it turns out that about 90% of the planet’s fresh water ice may not be on solid ground. Geologist John Goodge called the team’s findings “provocative” in an independent commentary on the new study, published Thursday in the journal Nature Geoscience.
“East Antarctica is typically considered from seismic tomography and geodetics to be ancient and generally stable,” according to Goodge, who studies continental tectonics with the nonprofit Planetary Science Institute. “[But] something else is going on at depth.” Continental divides Goodge speculates that this seemingly “coherent pull-apart system,” as presented in the new study, might help explain a variety of mysterious heat and water flows beneath this ice sheet’s surface, like that enormous subglacial lake identified in 2016 or some of the hundreds more like it.
The study’s authors, led by geophysicist Egidio Armadillo at the University of Genoa in Italy, agreed: “Because these basins underlie about half of the East Antarctic Ice Sheet, they are likely to heavily influence both ice-flow and landscape evolution,” the researchers wrote in their study, also published Thursday in Nature Geoscience. Armadillo’s team, coordinating across Europe and the U.K., developed their new understanding of Antarctica’s hidden bedrock via an exhaustive set of sensory data. Gravitational and magnetic anomalies were mapped via low-altitude airborne surveys. Ground surface features were mapped with seismic tools, using sound waves that vibrate through the ice and ping back information about subglacial landscapes in 3D. The grey, magenta, and cyan lines represent the apparent new fault lines discovered. Credit: Nature Geoscience All of this data—the fruits of “multi-national efforts to image within and below the ice sheet,” as Goodge put it—had already revealed that regions of the continent were “undergoing more rapid movement and ice-mass loss than previously recognized.” Armadillo’s team merely helped to explain why.
The mechanism Armadillo and his colleagues proposed for the formation of these fan-shaped basins is called “distributed rotational extension.” It involves points called Euler poles around which tectonic plates pivot or rotate rather than smash into each other or pull apart. The result is a bit like decks of cards being spread out on a table, thinning out the stack of Earth’s crust as it moves. An icy situation Goodge took pains to spell out the basins’ implications for melting Antarctic ice due to climate change and the risk of rising global sea levels.
The mere existence of these basins, he wrote, “could introduce widespread, systemic instability to the East Antarctic Ice Sheet” via thinner layers of Earth’s crust and more heat flow from below. On top of that, a series of fault-line “troughs” documented between the basins appear “tailor-made to promote outward flow of ice streams from the interior” into the world’s oceans, he said. That said, the team’s findings are unlikely to end this debate. As Goodge noted, Antarctica is “the last continental frontier of scientific exploration.” It’s still a very mysterious place, one that’s challenging to study given its inhospitable temperatures and extreme geography. Its “cryptic subglacial geology” might stay that way for a while. #Scientists #ContinentSized #Geological #Structure #Hiding #Beneath #AntarcticaAntarctica,Geology,mapping,Plate tectonics Scientists Found a Continent-Sized Geological Structure Hiding Beneath Antarctica
The East Antarctic Ice Sheet is almost unfathomably huge. Covering about 75% of the entire frigid continent (nearly everything on its side of the Transantarctic Mountains), the sheet covers about 3.9 million square miles (10.2 million square kilometers) and extends down 1.4 miles (2.2 km), on average, before coming into contact with Earth’s surface. At its deepest, the ice plunges down over 3 miles (4.9 km). For decades, scientists assumed that this literally continent-sized block of ice rested on an expansive and stable chunk of Earth’s crust known as a craton. A team of researchers has now complicated that picture—mapping a vast, interconnected geological structure that fans out from a troubling “tectonic deformation.” Beneath this ice sheet, thinner and more geologically recent slices of crusty lithosphere fan out into hidden valleys called “pull-apart basins.” These basins—30 elongated wedge-shaped valleys in total—constitute an entirely new, continental-scale geological region underneath Antarctica, in fact, one which the researchers have named the East Antarctic Fan-Shaped Basin Province (EAFBP). But it’s how they likely formed that has now caught researchers’ attention.
To put it bluntly, it turns out that about 90% of the planet’s fresh water ice may not be on solid ground. Geologist John Goodge called the team’s findings “provocative” in an independent commentary on the new study, published Thursday in the journal Nature Geoscience.
“East Antarctica is typically considered from seismic tomography and geodetics to be ancient and generally stable,” according to Goodge, who studies continental tectonics with the nonprofit Planetary Science Institute. “[But] something else is going on at depth.” Continental divides Goodge speculates that this seemingly “coherent pull-apart system,” as presented in the new study, might help explain a variety of mysterious heat and water flows beneath this ice sheet’s surface, like that enormous subglacial lake identified in 2016 or some of the hundreds more like it.
The study’s authors, led by geophysicist Egidio Armadillo at the University of Genoa in Italy, agreed: “Because these basins underlie about half of the East Antarctic Ice Sheet, they are likely to heavily influence both ice-flow and landscape evolution,” the researchers wrote in their study, also published Thursday in Nature Geoscience. Armadillo’s team, coordinating across Europe and the U.K., developed their new understanding of Antarctica’s hidden bedrock via an exhaustive set of sensory data. Gravitational and magnetic anomalies were mapped via low-altitude airborne surveys. Ground surface features were mapped with seismic tools, using sound waves that vibrate through the ice and ping back information about subglacial landscapes in 3D. The grey, magenta, and cyan lines represent the apparent new fault lines discovered. Credit: Nature Geoscience All of this data—the fruits of “multi-national efforts to image within and below the ice sheet,” as Goodge put it—had already revealed that regions of the continent were “undergoing more rapid movement and ice-mass loss than previously recognized.” Armadillo’s team merely helped to explain why.
The mechanism Armadillo and his colleagues proposed for the formation of these fan-shaped basins is called “distributed rotational extension.” It involves points called Euler poles around which tectonic plates pivot or rotate rather than smash into each other or pull apart. The result is a bit like decks of cards being spread out on a table, thinning out the stack of Earth’s crust as it moves. An icy situation Goodge took pains to spell out the basins’ implications for melting Antarctic ice due to climate change and the risk of rising global sea levels.
The mere existence of these basins, he wrote, “could introduce widespread, systemic instability to the East Antarctic Ice Sheet” via thinner layers of Earth’s crust and more heat flow from below. On top of that, a series of fault-line “troughs” documented between the basins appear “tailor-made to promote outward flow of ice streams from the interior” into the world’s oceans, he said. That said, the team’s findings are unlikely to end this debate. As Goodge noted, Antarctica is “the last continental frontier of scientific exploration.” It’s still a very mysterious place, one that’s challenging to study given its inhospitable temperatures and extreme geography. Its “cryptic subglacial geology” might stay that way for a while. #Scientists #ContinentSized #Geological #Structure #Hiding #Beneath #AntarcticaAntarctica,Geology,mapping,Plate tectonics](https://gizmodo.com/app/uploads/2026/06/East-Antarctic-Fan-shaped-Basin-Province.jpeg)
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