Dead satellite reveals lost continents.
Recent scientific discoveries have revealed continents from long ago hidden beneath Antarctica’s ice sheets using data from a satellite that has been inoperative for about five years.
This new research reveals a better understanding of the geological history of Antarctica over the last 200 million years. The data reveals that roughly 180 million years ago the main landmasses of Antarctica, India, and Australia separated from Gondwana. This separation resulted in a slow shift to their current locations.
The satellite used concerning these discoveries is known as the Gravity Field and Ocean Circulation Explorer (GOCE). GOCE was a European Space Agency (ESA) satellite that was in orbit from 2009 to 2013. During the four years of operation, GOCE mapped the gravity field on Earth with unmatched accuracy before being purposefully destroyed when re-entering the atmosphere. Since its destruction, scientists have studied the data of GOCE and have used it to create maps of the lithosphere of the Earth. The lithosphere is the tectonically active layer that contains the crust and outer mantle of the Earth.
These maps are used to sketch long-lost masses of land trapped within drifting continental plates known as cratons. Cratons have typically been hard to examine in the lithospheric structure of Antarctica because of the isolated location and huge ice sheets that obscure the underlying geology of Antarctica. The observations GOCE has provided has solved this problem significantly.
Using GOCE, scientists were able to locate ancient cratons below the ice fields of Eastern Antarctica and link them to the past neighbors in the region, India, and Australia. GOCE also revealed that Western Antarctica has a much thinner lithosphere, therefore lacking similar cratons.
The findings of GOCE are significant because they reveal that a combination of seismological and satellite gravity gradient imaging has great potential regarding increasing our understanding of the structure of the Earth. This is particularly true in previously hard to map regions such as Antarctica.