Ice flows like an enormous glacier, shaped by the terrain beneath
Bajo kilómetros de hielo antártico, un equipo internacional liderado por el geofísico Egidio Armadillo ha revelado una provincia geológica en forma de abanico compuesta por treinta cuencas interconectadas, oculta durante millones de años bajo el este del continente blanco. Esta arquitectura subterránea, probablemente anterior a la fragmentación de Gondwana, no es solo un vestigio del pasado: sigue moldeando el flujo del hielo que cubre la Antártida hoy, y con él, el destino de los niveles del mar en un planeta que se calienta. La Tierra guarda memorias largas, y a veces las revela justo cuando más las necesitamos.
- Una estructura geológica del tamaño de un continente ha permanecido invisible bajo el hielo antártico durante millones de años, y su descubrimiento reescribe lo que sabíamos sobre la historia tectónica del planeta.
- La provincia de cuencas en abanico sugiere que una zona de debilidad cortical antigua pudo haber desencadenado la separación entre la Antártida y Australia, un proceso que rediseñó la geografía del mundo.
- El equipo combinó radar, gravimetría, datos sísmicos y modelos de rebote isostático para reconstruir el paisaje subglacial, una hazaña técnica que convierte datos invisibles en mapas de un mundo enterrado.
- El hallazgo no es solo arqueología geológica: la topografía oculta controla cómo fluye el hielo sobre ella, y ese flujo determina cuánto subirá el mar si el calentamiento global acelera el deshielo antártico.
Bajo la capa de hielo de la Antártida oriental existe un mundo que la ciencia apenas comienza a descifrar. Un equipo internacional liderado por el geofísico Egidio Armadillo, de la Universidad de Génova, ha identificado una gigantesca provincia geológica compuesta por unas treinta cuencas interconectadas que se despliegan como un abanico desde un punto cercano al Polo Sur. Los resultados fueron publicados en Nature Geoscience.
Para llegar a este descubrimiento, los investigadores combinaron datos de radar, gravedad, magnetismo y sísmica, y los integraron con modelos de rebote isostático —el proceso por el cual la corteza terrestre se eleva al liberarse del peso del hielo— para reconstruir cómo sería el continente sin su cubierta glaciar. Lo que encontraron fue inesperado: una geometría radial que responde a un mecanismo de extensión rotacional, el mismo proceso por el que la corteza se abre desde un punto de pivote, como las varillas de un abanico.
Esta estructura probablemente se formó antes de que Gondwana, el antiguo supercontinente, comenzara a fragmentarse hace cientos de millones de años. Los científicos creen que la provincia pudo haber creado una zona de debilidad en la corteza que contribuyó a la eventual separación entre la Antártida y Australia. La misma arquitectura también habría dado forma a algunas de las cadenas montañosas más imponentes del continente, como las Montañas Gamburtsev.
Pero el hallazgo trasciende la historia geológica remota. El hielo antártico no es estático: fluye lentamente sobre el lecho rocoso, y la forma de ese terreno oculto influye directamente en su dinámica. Comprender mejor esa topografía subglacial permite afinar las proyecciones sobre cómo evolucionará la capa de hielo antártica y cuánto podría contribuir al aumento del nivel del mar en un contexto de cambio climático acelerado.
Beneath the Antarctic ice sheet lies a world that scientists are only beginning to map. A team of international researchers has now identified a colossal geological structure hidden under East Antarctica—a formation that remained buried for millions of years and may hold crucial clues about how our planet's continents came apart and how its ice behaves today.
The discovery was made by a group led by geophysicist Egidio Armadillo of the University of Genoa, with findings published in Nature Geoscience. Using a combination of radar, gravity measurements, magnetic data, and seismic studies, the team reconstructed what East Antarctica would look like if all its ice vanished. In doing so, they detected something unexpected: a massive geological province composed of roughly thirty interconnected basins fanning outward across the continent like an open hand. The researchers named it the Eastern Antarctic Fan-shaped Basin Province.
The geometry is striking. Many of the subglacial basins appear to radiate outward from a single point near the South Pole, arranged in a pattern that matches a geological process called rotational extension—the way the Earth's crust spreads outward from a pivot point, much as a fan opens. This mechanism likely shaped not only the basins themselves but also some of Antarctica's most dramatic hidden mountain ranges, including the Gamburtsev Mountains and portions of the Transantarctic range.
The structure probably formed before Gondwana, the ancient supercontinent that once held most of Earth's landmasses, began to break apart hundreds of millions of years ago. Scientists believe the fan-shaped province created a zone of weakness in the Earth's crust that may have contributed to the eventual separation of Antarctica from Australia. But this ancient architecture continues to matter. The ice sheet above does not sit still—it flows slowly like an enormous glacier, and its movement is shaped by the bedrock beneath. The shape of that hidden terrain influences how the ice moves, which in turn affects predictions about how Antarctic ice will behave as the climate changes and sea levels rise.
The research emerged from an effort to understand the subglacial landscape more precisely. The team incorporated a concept called isostatic rebound—the way land rises when it no longer bears the weight of massive ice. By layering this principle onto their radar and seismic data, they created maps that revealed the surprising fan pattern. The discovery opens a window onto a landscape that has been sealed under ice for millions of years, a landscape that continues to influence the behavior of one of Earth's most consequential ice sheets.
Notable Quotes
The ice does not remain immobile but flows slowly like an enormous glacier, and its movement is conditioned by the shape of the rocky bed beneath it— Research findings on Antarctic ice dynamics
The Hearth Conversation Another angle on the story
Why does the shape of the bedrock matter so much if it's buried under kilometers of ice?
Because ice doesn't just sit there—it flows. The shape of the ground underneath acts like a channel, directing where the ice moves and how fast. If you want to predict what happens to Antarctic ice as the climate warms, you need to know the terrain it's sliding across.
So this fan shape they discovered—is that unusual?
Very. Most geological structures don't arrange themselves in this radial pattern. What they found suggests a single, ancient tectonic event that pulled the crust outward from one point, like spokes on a wheel. That's not random geology.
And this connects to Gondwana breaking apart?
Yes. The weakness created by this fan-shaped structure may have been where the crust finally gave way when Gondwana fragmented. It's like finding the fault line that let continents drift apart.
How did they see all this if it's under ice?
They didn't see it directly. They used radar that penetrates ice, gravity measurements that detect density changes in rock, and seismic waves. Then they modeled what the land would look like if the ice weight were removed. The pattern emerged from that reconstruction.
Does this change what we know about Antarctica's future?
It refines it. The more precisely we understand what's underneath, the better our models can predict how ice will flow and how much sea level might rise. It's not a complete answer, but it's a crucial piece.