Lost Continents Hidden Deep Beneath Antarctica Ice Sheet Discovered From Space

Scientists have discovered the remnants of ancient lost continents hidden deep beneath Antarctica’s ice. Using the European Space Agency’s gravity mapping satellite, researchers were able to peer beneath the ice to map out the terrain below. ESA

Scientists have discovered the remnants of ancient lost continents hidden deep beneath Antarctica's ice. Using the European Space Agency's gravity mapping satellite, researchers were able to peer beneath the ice to map out the terrain below.

The findings, published in Scientific Reports, reveal a long-lost landscape littered with cratons—large, stable blocks of the Earth's crust that are remnants of ancient continents. They are part of the lithosphere—which consists of the crust and upper mantle—and are generally found in the center of modern continental plates. Studying these features allow researchers to understand the history of the Earth—and its future.

The ESA's Gravity Field and steady-state Ocean Circulation Explorer (GOCE) satellite was launched in 2009 to measure the pull of Earth's gravity. However, during its last year of operation, it was flown at an altitude of just 158 miles—meaning it could take extremely accurate measurements of localized gravity gradients. Using this data, the team was able to build up a patchwork 3D image of the lithosphere beneath Antarctica—including the cratons.

The European Space Agency’s Gravity Field and steady-state Ocean Circulation Explorer satellite mapped this bedrock topography of Antarctica. Kiel University/BAS

"Cratons are the ancient parts of the lithosphere and form the oldest cores of the continents. Understanding their structure and longevity hold key answers to unveil Earth's early history and how the solid Earth affects Earth evolution, linking ultimately to climate and the future of the Earth," Jörg Ebbing, from Kiel University, in Germany, told Newsweek. "Antarctica is in many respects still a blank spot, and despite new seismological results, we did not expect to see that the ancient part of East Antarctica is so heterogeneous."

He said with seismological research, it is easy to observe the difference between East and West Antarctica. "Our data seem to suggest that East Antarctica is not one craton but an amalgamation of cratonic parts," Ebbing noted. "This observation leads back to the breakup of the supercontinent Gondwana and the link of Antarctica to the surrounding continents."

Because Antarctica is covered in ice, taking direct samples of rocks is not possible. Instead, scientists have to work out how it might have moved over Earth's history by looking at its former neighboring continents—Australia and South America, for example. The latest findings indicate West Antarctica has a thinner crust and lithosphere than East Antarctica, which seems to be made up of old cratons and looks a bit like Australia and India.

"The new images show us the fundamental difference in the lithosphere beneath East and West Antarctica in agreement with previous seismic findings," co-author Fausto Ferraccioli, of the British Antarctic Survey, told Newsweek. "We also found a greater degree of complexity in the interior of East Antarctica than is apparent from current seismic views, suggesting that this part of the continent is a mosaic of old cratons and orogens (regions where continents collide). Some of these regions have clear ties to formerly adjacent continents in the supercontinent Gondwana—such as Australia, India and Africa."

Ferraccioli said they can use these findings to study the tectonic processes that affected Antarctica. "I expect this is going to help us understand the links between Antarctica and the rest of the continents better and also improve our knowledge of the influence of the lithosphere on the overlying ice sheets from a different gravity-derived perspective," he explained.

The latest findings are part of a bigger initiative to model Earth and gain a better understanding of the plate tectonics that shaped our planet. By gathering data on Antarctica's lithosphere, researchers will be able to better understand the structure of the frozen continent, allowing them to better comprehend how it might respond to climate change in the coming centuries.

"Also linked to this we will be producing new 3D models for Antarctica—including the development of new thermal models that are important to better constrain the heat delivered from the solid Earth to the base of the Antarctic ice sheet," Ferraccioli said.

This story has been updated to include comments from Fausto Ferraccioli, of the British Antarctic Survey​.