Dead Satellite Yields Fresh Data About Continents Hidden Beneath Antarctica
Scientists have used data from a satellite that has been dead for five years to create new maps of the geological history of Antarctica. The research condenses 200 million years of geological evolution in a 24-second animation.
The animation shows the tectonic impact of Antarctica splitting from the former landmass of Gondwana, which was one subsection of the supercontinent Pangaea. The shift begins approximately 180 million years ago when the landmass of Antarctica, India, and Australia broke away from Gondwana and moved slowly to positions we recognize them in today.
Dead satellite data still being used five years on
The new data comes from observations from the Gravity field and Ocean Circulation Explorer (GOCE), a European Space Agency (ESA) satellite that was in orbit from 2009 to 2013. The shard-wooing satellite flew at an altitude of just 255 km, almost 500 km closer to earth than a typical observation satellite in order to maximize its sensitivity to gravity.
During its tenure, the satellite mapped Earth’s gravity field before being intentionally destroyed on atmospheric reentry. Since its death, scientists have been poring over its data to create usable maps of Earth’s tectonically active layer that includes the planet’s crust and outer mantle called Earth’s lithosphere.
New look sheds light on history underneath the ice
The completed maps show the remains of former landmasses now trapped within drifting continental plates called cratons. While some of these formations have been well researched the cratons related to Antarctica have been very difficult to examine due to its remote location and the enormous ice sheets that cover its geology.
“These gravity images are revolutionizing our ability to study the least understood continent on Earth, Antarctica,” says co-author of the paper Fausto Ferraccioli, Science Leader of Geology and Geophysics at BAS. “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.”
Research could give insight into future geological behaviors
The data has already shown differences in East and West Antarctica. West Antarctica has a thinner crust and lithosphere compared to that of East Antarctica, which is closer in structure to the Australian and Indian continents. ESA’s GOCE mission scientist Roger Haagmans adds, “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.”
Aside from better understanding the history of the globes geology, the new research provides an interesting perspective on the way Antarctica has behaved over time and perhaps give insight into how Antarctica regions will respond to melting ice.
Germany’s Kiel University and the British Antarctic Survey published their latest GOCE-based findings this week in the journal Scientific Reports.