Beneath its layers of ice, Antarctica holds secrets of continents that preceded the creation of the ice-covered land at the South Pole, according to new research.
Study leader Jörg Ebbing, a geoscientist at Kiel University in Germany, said that the vast continent contains the cores of continents that existed before Antarctica was formed, according to LiveScience.
“This observation leads back to the break-up of the supercontinent Gondwana and the link of Antarctica to the surrounding continents,” Ebbing said.
Scientists believe that at one time, all of the Southern Hemisphere’s continents were part of one vast super continent called Gondwana. Current theory suggests the continents split apart 180 million years ago.
Some of the evidence for that is found in an area known as the Mawson Craton, which has a matching piece of land that is geologically similar in southern Australia.
The new research did not come from digging into the ice that hold Antarctica captive, but through a sophisticated use of the Gravity field and Ocean Circulation Explorer satellite that generated data about gravity and software to look below the ice to see what stories the rock would tell. The satellite orbited the Earth from 2009 through 2013.
“The satellite gravity data can be combined with seismological data to produce more-consistent images of the crust and upper mantle in 3D, which is crucial to understand how plate tectonics and deep mantle dynamics interact,” Ebbing said.
“These gravity images are revolutionizing our ability to study the least understood continent on Earth, Antarctica,” said Fausto Ferraccioli, the science leader of geology and geophysics at the British Antarctic Survey, according to the European Space Agency.
Ferraccioli said that scientists now know the eastern and western halves of Antarctica are very different.
“The new images show us the fundamental difference in the lithosphere beneath East and West Antarctica in agreement with previous seismic findings,” Ferraccioli said, according to Smithsonian.
“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. Some of these regions have clear ties to formerly adjacent continents in the supercontinent Gondwana—such as Australia, India and Africa,” he said.
“In East Antarctica, we see an exciting mosaic of geological features that reveal fundamental similarities and differences between the crust beneath Antarctica and other continents it was joined to until 160 million years ago,” Ferraccioli said, according to Space.com.
What they found was that in addition to areas where once-similar regions are now divided, there are regions called orogens, where pieces of continents collided, causing mountains to form.
In one area where the crust was very thin, researchers found evidence for what’s known as a mantle plume, in which volcanic material from the Earth’s core strains against the Earth’s surface, sometimes causing volcanoes.
“It is exciting to see that direct use of the gravity gradients, which were measured for the first time ever with GOCE, leads to a fresh independent look inside Earth – even below a thick sheet of ice, said ESA scientist Roger Haagmans.
“It also provides context of how continents were possibly connected in the past before they drifted apart owing to plate motion,” he said.
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