Discovery of Ancient Subglacial Rivers Reveals Hidden Antarctic Landscape



Antarctica, the desolate land of ice and snow that we know today, was once a thriving ecosystem filled with rivers, forests, and abundant life. In a groundbreaking study, scientists have managed to unveil a hidden ancient landscape buried beneath the massive ice sheet of the continent. Using satellite observations and ice-penetrating radar, researchers have discovered a vast landscape in East Antarctica’s Wilkes Land region, bordering the Indian Ocean. This landscape spans an area comparable to Belgium or the state of Maryland and is believed to have formed at least 14 million years ago, and possibly even earlier, when Antarctica transitioned into an icy wasteland.

Stewart Jamieson, a glaciology professor at Durham University and co-leader of the study, describes the unearthed landscape as a “snapshot of the past.” While it is challenging to visualize the exact appearance of this lost world before it was engulfed by ice, scientists believe that it was considerably warmer. Depending on the timeframe, the climate could have ranged from the present-day Patagonian climate to something akin to a tropical environment. Scientists have even discovered ancient palm tree pollen not far from the study site, further supporting the notion of a once-lush environment. Although the fossil record is incomplete, it is reasonable to assume that this ancient landscape was teeming with wildlife.

The ice above this ancient landscape measures approximately 2.2-3 km in thickness, making the underlying land even less known than the surface of Mars. To uncover the mysteries hidden within, researchers propose drilling through the ice to retrieve core samples of sediments from below. Similar studies conducted in Greenland, dating back 2 million years, have already provided valuable insights into ancient flora and fauna. By employing satellite observations of the ice surface, which can occasionally mimic the contours of the buried landscape, in combination with ice-penetrating radar data collected from a plane flying over the site, scientists have managed to reveal hidden landscapes beneath Antarctica’s ice in previous studies. However, the newly discovered landscape in Wilkes Land is the first of its kind.

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Neil Ross, a professor of polar science and environmental geophysics at Newcastle University and co-leader of the study, emphasizes that the landscape underwent extensive modifications due to various processes influenced by rivers, tectonics, and glaciation over a remarkably long geological period. Roughly 34 million years ago, before Antarctica succumbed to its frozen state, the landscape and flora would have resembled the cold temperate rainforests found in Tasmania, New Zealand, and South America’s Patagonia region. Antarctica was once part of the Gondwana supercontinent, which also included present-day Africa, South America, Australia, the Indian subcontinent, and the Arabian Peninsula. It eventually separated and became isolated through a geological process known as plate tectonics.

According to Jamieson, when Antarctica’s climate was warmer, rivers flowed across the newly identified landscape, eventually reaching a continental coastline that formed as other land masses broke away. As the climate cooled, small glaciers developed near the rivers, contributing to the deepening of valleys through glacial erosion. Eventually, the climate cooled even further, resulting in the growth of an ice sheet that covered the entire continent, obliterating any preexisting glaciers. This marked a significant change in conditions between the base of the ice and the landscape, as the environment became exceptionally cold. Consequently, the landscape was no longer susceptible to erosion. Instead, it remained preserved for an astonishing 34 million years.

The discovery of this ancient landscape provides valuable insights into Earth’s history and the environmental changes it has undergone. By studying these hidden landscapes and the remnants of ancient flora and fauna, scientists can piece together the puzzle of our planet’s past. The complexities of Antarctica’s geological history are gradually being unraveled, shedding light on the extraordinary transformations that have shaped our world over millions of years.

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