Data From a Dead Satellite Reveals Lost Continents Under Antarctica
“These gravity images are revolutionizing our ability to study the least understood continent on Earth—Antarctica.”
Scientists have detected long-lost continents hidden under Antarctica’s ice sheets using data from a satellite that has been dead for five years.
The new research, published in Scientific Reports, sheds light on the murky geological history of Antarctica over the past 200 million years, and condenses it in this 24-second animation. The video reconstructs the tectonic fallout of Antarctica splitting from the bygone landmass of Gondwana, which was one subsection of the supercontinent Pangaea. Beginning around 180 million years ago, the core landmasses of Antarctica, India, and Australia broke off from Gondwana, and slowly shifted to their current locations.
The visualization is based on observations from the Gravity field and Ocean Circulation Explorer (GOCE), a European Space Agency (ESA) satellite that operated in orbit from 2009 to 2013. For those four years, the satellite mapped out Earth’s gravity field with unprecedented precision, before it was deliberately destroyed in atmospheric reentry. Since then scientists have combed over its measurements to create maps of Earth’s lithosphere, the tectonically active layer that includes the planet’s crust and outer mantle.
These maps sketch out the remnants of long-lost landmasses trapped within drifting continental plates called cratons. While some cratons are already well-understood, Antarctica’s lithospheric structure is tough to examine because of its remote location and the enormous ice sheets that obscure its underlying geology.
“These gravity images are revolutionizing our ability to study the least understood continent on Earth—Antarctica,” said study co-author Fausto Ferraccioli, science leader of geology and Geophysics at the British Antarctic Survey, in a statement. “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.”
Using GOCE’s observations, the team was able to spot ancient cratons underneath the ice fields of East Antarctica and link them to the region’s past neighbors, India and Australia. West Antarctica, in contrast, has a thinner lithosphere that lacks these massive cratons.
“The comparisons demonstrate that the combination of seismological, and satellite gravity gradient imaging has significant potential to enhance our knowledge of Earth’s structure,” the study concluded. This is especially true, the researchers added, about “remote frontiers like the Antarctic continent, where even basic knowledge of lithospheric scale features remains incomplete.”
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