Researchers have discovered the remains of lost continents, hidden deep under the Antarctic ice, using gravity data from ESA's GOCE Satellite.
The GOCE territory (Gravity field and Ocean Circulation Explorer) has blinded the Earth for more than four years, from 2009 to 2013. Using GOCE's gravitational data set, researchers have gained new insights into Antarctic structure and properties, one of the most important but less understood parts of the Earth.
GOCE analyzes ground masses by measuring changes in Earth's gravitational field. Because the masses of the continents and deep within the Earth are not coherent or evenly distributed, the gravitational force varies from one place to another, and these gravitational anomalies can be used to solve structures deep beneath the surface.
During his four-year mission, GOCE flew at an altitude of just 255 km, more than 500 km closer to Earth observation satellites, and measured the gravity of Earth more precisely than any other mission. This distance also allowed the GOCE satellite to make very accurate measurements of Earth's gravity over the Antarctic, which is a relatively challenging place because of its distance and thick ice sheet.
Satellite gravity data, combined with seismological data, has produced more accurate 3D maps of the deep Antarctic interiors, and has provided researchers with an excellent tool to investigate the structure of the least explored region on earth.
"These gravitational images revolutionize our ability to study the least understood continent on Earth, Antarctica," said co-author Fausto Ferraccioli, Scientific Leader of Geology and Geophysics at the British Antarctic Survey (BAS).
"In East Antarctica we see an interesting mosaic of geological features that reveals fundamental similarities and differences between the crust beneath the Antarctic and other continents to which it has joined 160 million years ago."
The gravity data show that Western Antarctica has a thinner crust and a topcoat than East Antarctica, which is made up of a mosaic of old cratons separated by younger orogens, revealing its ties to Africa, India, Australia, Zealand and South America.
"It is interesting to note that the direct use of gravitational gradients, which were measured for the first time with GOCE, leads to a new independent vision inside the Earth – even under ice thickness," said Roger Haagmans, ESA. "It also provides a context on how the continents could be connected in the past before they deviate from the plaque movement."