A new study shows that atmospheric rivers may be responsible for up to 90% of Antarctica’s annual precipitation.A groundbreaking tectonic model has emerged from the depths of East Antarctica’s frozen landscape, revealing a colossal rotational extension process that shaped a striking handheld-fan-shaped structural feature beneath the ice. This vast subglacial basin province, meticulously reconstructed by geoscientists, offers compelling evidence of continental-scale deformation that redefined East Antarctica’s crustal architecture. The implications of this discovery reverberate beyond geological curiosity, stirring fresh insights into the ancient tectonic forces that sculpted one of the planet’s most enigmatic continents and linking these subterranean transformations to the dynamics of Gondwana’s fragmentation.
At the heart of this tectonic revelation lies a single, continent-wide mechanism dominated by rotational extension—an earth-shaping process that not only dramatically reworked pre-existing structures but also set in motion subsequent geological phenomena of monumental scale. This model suggests that the rotational extension instigated a complex reconfiguration of East Antarctic lithosphere, fundamentally influencing the geological evolution of critical mountain ranges, including the Gamburtsev and Transantarctic Mountains. The resulting deformation and segmentation within these ranges underpin the formation of conjugate continental margins, which form a semi-circular pattern between Antarctica and Australia, illuminating previously obscure steps in the precursory tectonic stages leading up to the ultimate breakup of Gondwana.
One of the most intriguing aspects of this tectonic scenario concerns the spatial coincidence between the fan-shaped province’s pivot point and the Euler poles inferred for the extension between East and West Antarctica after approximately 34 million years ago. Although there remains uncertainty surrounding the precise location of these rotational poles, the close alignment raises provocative questions about the stability of deformation centers over geological time scales. This alignment further suggests a potential causal link bridging intraplate deformation mechanisms with the broader plate tectonic motions that characterized the region during late Cenozoic rifting and continental evolution.
Remarkably, this fan-like rotational deformation appears confined exclusively to the Antarctic lithosphere. Detailed analyses fail to identify any continuation of these features into the adjacent Australian continent, signaling a previously unrecognized intraplate deformation zone within East Antarctica. This discovery holds profound implications for reconciling longstanding inconsistencies in tectonic reconstructions, particularly in refining the fit between the Australian and Antarctic continental margins. Identifying this localized deformation zone may illuminate why some plate reconstructions have documented unusually broad crustal overlaps and difficult-to-explain mismatches across conjugate basement terranes and major fault systems.
Beyond its tectonic significance, this rotational extension model profoundly informs our understanding of the East Antarctic Ice Sheet’s origins and dynamic behaviour. Initiated approximately 34 million years ago, the ice sheet’s evolution intersects the geological fabric sculpted by the extensional forces operating beneath it. The subglacial basins forming the handheld-fan-like structure influence not only the basal topography but also the dynamic feedback mechanisms governing ice sheet retreat and advance. Due to ongoing subsidence and cooling of the crust following extension, many of these basin floors lie near or below modern mean sea level, engendering conditions that likely amplify the ice sheet’s sensitivity and vulnerability to climatic perturbations.
Topographically, the segmentation of major mountain ranges in East Antarctica via a network of east-west oriented circular shear belts has played a pivotal role in directing glacial pathways. Shear zones along these belts create structural weaknesses exploited by massive outlet glaciers such as Byrd, Beardmore, Nimrod, David, Priestley, and Tucker. These glaciers have incised profound troughs into the mountains, driving further isostatic uplift of the peaks and perpetuating a cycle of tectonic and glacial interaction. This dynamic interplay exemplifies how ancient tectonic architecture continues to govern present-day cryospheric and geomorphological processes in Antarctica’s interior.
Similarly, the prominent fan-shaped boundary system oriented roughly north-south within the East Antarctic subglacial basin province appears intimately linked to the positions of some of the continent’s most significant outlet glaciers on its coastal margins. Totten, Vanderford, Denman, Frost, and Amery glaciers align closely with major basin boundaries, suggesting that structural geology fundamentally controls glacial drainage patterns. This tectonic-ice sheet interface underscores the critical role geological processes dating back more than 150 million years play in determining the contemporary ice sheet’s behaviour and its response to environmental change.
From a broader geodynamic perspective, the existence of this rotational extension province challenges conventional interpretations of East Antarctica’s lithospheric rigidity. Instead of behaving as a monolithic block, the continent’s eastern sector underwent profound internal distortion and segmentation, contesting previous models that invoked more homogeneous deformation. This nuanced understanding demands re-evaluation of geodynamic models that couple onshore structural features with offshore fracture zone studies, highlighting the complementary roles of both deep and shallow earth processes in continent-scale reorganization.
Moreover, the timeframe of deformation pinned to the EAFBP coincides intriguingly with marked geological shifts at the Paleogene-Neogene boundary. This temporal intersection accentuates the role of tectonics in modulating the environmental context for large-scale ice sheet nucleation and persistence. The established relationship provides a unique opportunity to integrate tectonic forcing into climate and cryosphere models, potentially refining predictions of ice sheet behaviour within a warming world.
Delineating the rotational extension process also sheds light on the segmentation observed within the Transantarctic Mountains and the West Antarctic Rift System. These structural discontinuities reveal how the continent’s lithosphere accommodated strain over millions of years, via curved shear belts and fault zones demarcating discrete tectonic blocks. Such segmentation arguably fostered localized uplift and subsidence patterns, influencing sediment deposition regimes and geomorphological evolution throughout the continent’s interior.
Perhaps most strikingly, this in-depth investigation emphasizes the enduring influence of early Mesozoic tectonics on shaping Antarctica’s geological framework, long after the initial stages of Gondwana’s breakup. By identifying a singular large-scale rotational extension event as a formative agent, this model unites seemingly disparate observations—from subglacial basin geometry to mountain range uplift—into a cohesive tectonic narrative. This unified perspective provides a valuable blueprint for reinterpreting the continent’s evolutionary trajectory and contextualizing its role within global plate tectonics.
The pioneering interdisciplinary approach harnessed to unravel this subglacial province integrates geophysical imaging, structural geology, and tectonic reconstruction techniques. Detailed gravity anomaly mapping and seismic reflection profiles provide unprecedented subsurface illumination, enabling researchers to differentiate subtle deformation patterns beneath kilometers of ice. The resulting dataset affords unparalleled clarity into the three-dimensional architecture of East Antarctica’s crust, setting a benchmark for future Antarctic geoscience research.
In conclusion, this discovery of a fan-shaped rotational extension province unveils an overlooked GPS of tectonic activity underpinning the East Antarctic lithosphere. It highlights the dynamic and evolving nature of continental interiors, traditionally considered tectonically inert. As our understanding deepens, so too does the appreciation for how ancient geological forces continue to wield influence over ice dynamics, mountain formation, and continental fragmentation—processes that shape Earth both past and present.
The identification of this rotational extension province opens new avenues for refining plate reconstructions involving Antarctica and Australia. It simultaneously challenges simplifications inherent in previous models, advocating for nuanced treatments of intraplate deformation zones. This progression promises enhanced geological models capable of incorporating the intricate interplay of forces molding Earth’s least accessible continental frontier.
Ultimately, these insights carry profound ramifications for predicting Antarctica’s future amid climate change. Given the pivotal role tectonic features play in modulating ice sheet sensitivity and stability, understanding their genesis and evolution becomes crucial for anticipating responses to accelerating global warming. This research thus exemplifies the vital synergy between geological sciences and cryospheric studies essential for informed stewardship of polar environments.
Subject of Research: The formation and tectonic evolution of a fan-shaped subglacial basin province in East Antarctica driven by rotational extension.
Article Title: A fan-shaped subglacial basin province in East Antarctica formed by rotational extension.
Article References:
Armadillo, E., Rizzello, D., Balbi, P. et al. A fan-shaped subglacial basin province in East Antarctica formed by rotational extension. Nat. Geosci. (2026). https://doi.org/10.1038/s41561-026-01991-6
Image Credits: AI Generated
DOI: https://doi.org/10.1038/s41561-026-01991-6
Keywords: East Antarctica, rotational extension, subglacial basins, tectonic deformation, Gondwana breakup, ice sheet dynamics, Transantarctic Mountains, Gamburtsev Mountains, intraplate deformation, East Antarctic Ice Sheet, plate reconstructions, lithospheric segmentation, continental rifting, conjugate margins
A new study shows that atmospheric rivers may be responsible for up to 90% of Antarctica’s annual precipitation.A new study shows that atmospheric rivers may be responsible for up to 90% of Antarctica’s annual precipitation.
Deep below Antarctica, clues to an ancient puzzle with cosmic origins have remained trapped in the southernmost continent’s ice for tens of thousands of years—until now.
Researchers have unearthed new evidence of the presence of iron-60, a rare radioactive isotope of iron linked to stellar explosions, captured in Antarctic ice estimated to be up to 80,000 years old.
Because this rare iron isotope cannot form naturally on Earth under most circumstances, its origin is likely traced to the deaths of massive stars, in cataclysmic cosmic events that eject rare-Earth isotopes like iron-60 during supernova explosions.
Fortunately, this radioactive cosmic messenger, which has a half-life of around 2.6 million years, can be preserved following such large-scale cosmic events, becoming entombed in deep-sea sediments and in ice covering the surface of Antarctica.
The result is what scientists liken to the ancient cosmic “fingerprints” of past stellar cataclysms that can be traced all the way to Earth. The discovery was reported in a paper published in Physical Review Letters.
Despite being one of the least-mapped surfaces in the entire Solar System by some estimates, over the last 35-million years, the accumulation of ice on Antarctica’s surface has slowly preserved a veritable “time capsule” of information about our planet’s geological past.
Accessing this deep geological history is as simple as drilling cores deep into Antarctica’s ice, which formed the basis of research led by German astrophysicist Dominik Koll, a researcher with the Helmholtz-Zentrum Dresden-Rossendorf, a Dresden-based research laboratory, which began in 2019.
However, the initial discoveries that prompted this research required no drilling at all—initial examination of fresh snow in Antarctica had already revealed the presence of iron-60, prompting a deeper search for past accumulations of this rare-Earth isotope.
Based on ice core analysis, additional signatures associated with stellar explosions have now been discovered deeper in our planet’s icy Antarctic archives, dating back to periods between around 40,000 and 81,000 years ago.
Koll and his colleagues relied on samples collected in association with a research effort called the European Project for Ice Coring in Antarctica, or EPICA, in which portions of the ice cores were melted to reveal the presence of iron-60, which they counted atom-for-atom.
As they had hoped to find, a greater number of iron-60 atoms was present than would be expected based solely on background sources, meaning the rest is almost certainly of cosmic origin.
Intriguingly, the fact that far lower concentrations of iron-60 appeared to be present in ice from Earth’s long distant past, when compared to samples like those from fresh snow obtained by Koll and his team beginning in 2019, suggest that the region of space our Solar System is currently traversing, known as the Local Interstellar Cloud (LIC), is effectively “a cosmic archive for supernova-produced [iron-60].”
Based on this, Koll and his colleagues report that the imprinted iron-60 profile over time points to strong evidence for changes in the local interstellar environment over the last 80,000 years, as represented in the EPICA ice samples.
Presently, astronomers are uncertain about the origins of the LIC, although the new findings suggest it has undergone significant changes over the last 100,000 years or so.
One thing that seems evident, based on the changes in the abundance of iron-60 throughout time, is that the LIC appears to have regions that possess more of it than others—very likely leftover from past stellar explosions.
Fundamentally, Koll and his colleagues say their recent findings align well with a supernova origin for the samples they uncovered, offering a unique opportunity to probe the ongoing mysteries of the LIC using relatively easily accessible ice cores from our planet’s southern continent.
The team’s findings were reported in a recent paper, “Local Interstellar Cloud structure imprinted in Antarctic ice by supernova 60Fe,” which appeared in Physical Review Letters.
Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. A longtime reporter on science, defense, and technology with a focus on space and astronomy, he can be reached at micah@thedebrief.org. Follow him on X @MicahHanks, and at micahhanks.com.
Antarctica has been impacted by three major events, which researchers have identified as a “perfect storm” that could finally initiate major melting on the icy continent, with major implications for exacerbating climate change.
According to new University of Southampton research, these events have begun a spiral that could move the global oceans from a hedge against climate change, to one of its primary drivers.
In a recent paper published in Science Advances, the team behind the study used satellite data to identify the root causes of record-low sea ice in the Antarctic and the potential future effects on the global climate.
While other parts of the world have been feeling the effects of global climate change for some time, it was only about a decade ago, in 2015, that Antarctic sea levels stopped rising and began retreating. The reason for this sudden reversal perplexed scientists until the University of Southampton team finally identified a series of Southern Ocean events that snowballed into a major climate concern, as they pulled up warm, salty water from below the surface.
By 2023, this chain of events had destroyed enough ice to cover Greenland, pushing the lows ever further.
“Antarctic sea ice in the Southern Ocean helps drive the planet’s ocean overturning circulation,” said lead author Dr. Aditya Narayanan, an oceanographer from the University of Southampton. “However, since 2015, the region has undergone a huge transformation, with extreme ice loss around the continent.”
“What started as a slow build-up of deep-sea heat under the Antarctic sea ice was followed by a violent mixing of water, ending in a vicious cycle where it’s too warm to let ice recover,” Dr. Narayanan says. “It’s concerning because massive loss of sea ice destabilizes the world’s ocean current systems, warming our planet far quicker than expected.”
The team used an advanced ice-measuring program that combined two approaches to identify three specific events responsible for the cascading ice loss.
“We use a combination of satellite observations and computer models — both of which are part of long-running international efforts,” Dr. Narayanan told The Debrief in an email. “The satellite data come from the National Snow and Ice Data Center (NSIDC), which compiles and distributes global sea ice records.”
“These measurements rely on instruments such as the Advanced Microwave Scanning Radiometer 2 (AMSR2), operated by the Japan Aerospace Exploration Agency (JAXA),” Dr. Narayanan added. “These sensors can ‘see’ through clouds and darkness, allowing us to track sea ice year-round.”
The Southampton team then ran this data through the Southern Ocean State Estimate, an advanced computer model created at the Scripps Institution of Oceanography.
“This is not just a standalone simulation—it combines the laws of physics with real-world observations, such as temperature, salinity, and sea ice data,” Dr. Narayanan said. You can think of it as a model that is constantly guided by observations, so it stays close to what is actually happening in the ocean.”
The issues began around 2013, when strong winds raised Circumpolar Deep Water, a warm, salty solution from the deep. Then, in 2015, stronger winds mixed that water directly into the surface layer, producing the rapid ice loss observed at the time, concentrated in the east. By 2018, surface water had reached a threshold at which so much warm, salty water had surfaced that ice formation became difficult, reinforcing the cycle.
The team discovered that this oceanic ice loss is primarily occurring in the East Antarctic, where the deepwater upsurge is primarily occurring. The West is not in the clear, though, as intense cloud cover over the subtropics has now heated the ocean, leading to major ice melt between 2016 and 2019.
“More recent observations, including near-real-time data from the National Snow and Ice Data Center(NSIDC), show that parts of West Antarctica, especially near the Antarctic Peninsula, are again experiencing low sea ice in certain seasons,” Dr. Narayanan told The Debrief. “Without carrying out a specific study, it is difficult to pinpoint a single cause for these recent changes.”
“Most likely, they reflect a combination of atmospheric conditions, such as clouds and winds, and heat being delivered by the ocean,” Narayanan said.
“This isn’t just a regional problem, Antarctic sea ice acts as Earth’s mirror, reflecting solar radiation back into space,” said co-author Dr. Alessandro Silvano, also from the University of Southampton. “Its loss could destabilize the currents that store heat and carbon in the ocean, accelerating global warming, and also destabilize ice shelves that prevent glaciers from sliding into the sea, raising global sea levels.”
The researchers warn that anthropogenic climate change is fueling the warm winds driving these events in the Antarctic.
“Were these trends to persist, the planet could experience a ‘prolonged low sea-ice state,’” said co-author Professor Alberto Naveira Garabato from the University of Southampton.
“If the low sea-ice coverage prevails into 2030 and beyond, the ocean may transition from a stabilizer of the world’s climate to a powerful new driver of global warming,” Garabato added.
The paper, “Compound Drivers of Antarctic Sea Ice Loss and Southern Ocean Destratification,” appeared in Science Advances on May 8, 2026.
Ryan Whalen covers science and technology for The Debrief. He holds an MA in History and a Master of Library and Information Science with a certificate in Data Science. He can be contacted at ryan@thedebrief.org, and follow him on Twitter @mdntwvlf.
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