Enhanced views of Earth tectonics
Scientists from Germany’s Kiel University and British Antarctic Survey (BAS) have used data from the European Space Agency (ESA), Gravity field and steady-state Ocean Circulation Explorer (GOCE) mission to unveil key geological features of the Earth’s lithosphere – the rigid outer layer that includes the crust and the upper mantle.
Published this week in the journal Scientific Reports the study is a step forward in the quest to image the structure and setting of different continents using satellite gravity data, including Antarctica, the least understood piece of the whole plate tectonic puzzle. Satellite gravity provides a new tool to link the remote and ice-covered continent with the rest of the Earth. This improves our understanding of Antarctica’s deep structure, which is particularly important, as the properties of its lithosphere can also influence the overlying ice sheets.
GOCE measures differences in horizontal and vertical components of the gravity field – known as gradients. These gradients can be complex to interpret and so the authors combined these to produce simpler ‘curvature images’ that reveal large-scale tectonic features of the Earth more clearly.
Lead author, Prof. Jörg Ebbing from the Kiel University said:
“Our new satellite gravity gradient images improve our knowledge of Earth’s deep structure. The satellite gravity data can be combined with seismological data to produce more consistent images of the crust and upper mantle in 3D. This is crucial to understanding how plate tectonics and deep mantle dynamics interact”.
Fausto Ferraccioli, Science Leader of Geology and Geophysics at the British Antarctic Survey and co-author of the study, said,
“Satellite gravity is revolutionizing our ability to study the lithosphere of the entire Earth, including its least understood continent, Antarctica. In East Antarctica, for example, we now begin to see a more complex mosaic of ancient lithosphere provinces. GOCE shows us fundamental similarities but also unexpected differences between its lithosphere and other continents, to which it was joined until 160 million years ago”.
The new study presents a view of the Earth’s continental crust and upper mantle not previously achievable using global seismic models alone. The authors noted that, despite their similar seismic characteristics, there are contrasts in the gravity signatures for ancient parts of the lithosphere (known as cratons), indicating differences in their deep structure and composition. These features are important. Because they form the oldest cores of the lithosphere, they hold key records of Earth’s early history.
ENDS
Issued by the Press Office at British Antarctic Survey:
Layla Batchellier, Press Officer, British Antarctic Survey, tel: +44 (0)1223 221506, email: laytch@bas.ac.uk
Athena Dinar, Senior PR & Communications Manager, British Antarctic Survey, tel: +44 (0)1223 221 441; mobile: +44 (0)7909 008516; email: amdi@bas.ac.uk
Claudia Eulitz, Press Officer, Kiel University, tel: +49 431 880-7110, e-mail: ceulitz@uv.uni-kiel.de
Honora Rider, Communication Department, European Space Agency (ESTEC), tel: +31 71 5655206;
e-mail: Honora.Rider@esa.int
Citation: Ebbing, J., Haas, P., Ferraccioli, F., Pappa, F., Szwillus W., and Bouman J. Earth tectonics as seen by GOCE – Enhanced satellite gravity gradient imaging. Scientific Reports, DOI: 10.1038/s41598-018-34733-9.
More detail about GOCE+Antarctica – Dynamic Antarctic Lithosphere:
https://www.bas.ac.uk/project/goceantarctica/
More detail about 3D+Earth – A Dynamic Living Planet:
https://www.3dearth.uni-kiel.de/en
British Antarctic Survey (BAS), an institute of the Natural Environment Research Council (NERC), delivers and enables world-leading interdisciplinary research in the Polar Regions. Its skilled science and support staff based in Cambridge, Antarctica and the Arctic, work together to deliver research that uses the Polar Regions to advance our understanding of Earth as a sustainable planet. Through its extensive logistic capability and know-how BAS facilitates access for the British and international science community to the UK polar research operation. Numerous national and international collaborations, combined with an excellent infrastructure help sustain a world leading position for the UK in Antarctic affairs. For more information visit www.bas.ac.uk
NERC is part of UK Research and Innovation
Kiel University (also referred to as the CAU) uses research, teaching and the transfer of science to address the great challenges of our time in health, environmental and cultural change, nutrition and energy. In doing so, it ensures peace and preserves livelihoods for future generations. The CAU uses responsible actions to make sure that scientific discoveries are transferred into all sectors of our society by interdisciplinary thought – regardless of short-lived trends – where they are incorporated into political, economic and social decisions aimed at securing peace and prosperity.
More information at www.uni-kiel.de/en
