Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Geoscientists from the Alfred Wegener Institute are back from an expedition to the Labrador Sea

22.07.2009
Indications for volcanic eruptions in the younger geological history found

Scientists from the Alfred Wegener Institute have researched the geology of the seabed in the Labrador Sea on board of the research vessel Maria S. Merian.

They have studied the so-called Eirik Drift at the southern tip of Greenland, a structure of several hundred kilometres length formed like a ridge. They discovered a submarine mountain (seamount) at the south-western fringe of their area of investigation that indicates volcanic eruptions during the past few million years.

The Eirik Drift rises 2,500 m above the surrounding seabed at the southern tip of Greenland. Sediments have been depositing there for the last ten million years, forming a ridge-like structure. These sediments are ablated by ocean currents in the Greenland Sea and deposited in the Labrador Sea. This is also known to be the case with sand displacements caused by ocean currents, for example on Sylt. Caused by changing climate - the transition from warmer times to our current climate - the current drifted and changed its strength. Additionally, icebergs transport rock material from Greenland onto the seabed. Glaciers planed it off the island, and on breaking apart into icebergs, deposited it all over the ocean. Caused by the constantly expanding and melting ice surface during the geological cycles of glacials and interglacials, this material finds its way into the Eirik Drift, too.

Therefore, the Eirik Drift is an archive for the activity of Greenland's western boundary current and the dynamics of Greenland ice cover. Climate changes and current shifts of the last ten million years can be examined here. First results show that the drift shifted strongly to the North and the West. This event took place about 5.6 million years ago. A sediment drift can be observed for the period prior to that, but velocity and path of the current changed strongly. Researchers will be able to further analyse these data by means of computer models in order to describe these changes in more detail.

The researchers discovered something unexpected during the seismic investigation using a recording cable of 3.000 m length: "Surprisingly, an unknown elevation appeared on the images of the subsurface in the western area of the Eirik Drift, which almost breaks through the sediments to the top of the seabed at two places," reports chief scientist Dr Gabriele Uenzelmann-Neben from the Alfred Wegener Institute for Polar and Marine Research in the Helmholtz Association. "The sedimentary layers are disturbed," the geophysicist continues. This elevation at the seabed, called Mount Maria S. Merian by the researchers, is about 1.500 m high - approximately as high as the Feldberg in the Black Forest. The seamount was formed by volcanism which pushed sediments upwards. Even the youngest sediment packages are affected by this movement.

It can therefore be concluded that this is a young event have occurred during the last few million years. This result changes the picture of the geological development of the outer part of the Labrador Sea. So far it was assumed that the formation of the seafloor in the Labrador Sea (tectonic activity) ended about 45 million years ago. The discovery of the seamount indicates that the seabed at the exit of the Labrador Sea changed in more recent times. A distinct changing seabed has an enormous impact on the circulation paths of deepwater, which maintains ocean currents like the Gulf Stream.

The expedition of RV Maria S. Merian, operated by the Leitstelle Merian/Meteor of the University of Hamburg, began June 17th 2009 in Reykjavik where it also ended July 13th.

Further information on this research project: http://www.awi.de/en/research/research_divisions/geosciences/geophysics/

projects/marine_geophysics_arctic/eirik_drift/?0=

The Alfred Wegener Institute carries out research in the Arctic and Antarctic as well as in the high and mid latitude oceans. The institute coordinates German polar research and provides international science with important infrastructure, e.g. the research icebreaker Polarstern and research stations in the Arctic and Antarctic. The Alfred Wegener Institute is one of 16 research centres within the Helmholtz Association, Germany's largest scientific organization.

Margarete Pauls | idw
Further information:
http://www.awi.de/

More articles from Earth Sciences:

nachricht A close-up look at an uncommon underwater eruption
11.01.2018 | Woods Hole Oceanographic Institution

nachricht Environmental history told by sludge: Global warming lets the dead zones in the Black Sea grow
10.01.2018 | Leibniz-Institut für Ostseeforschung Warnemünde

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Scientists decipher key principle behind reaction of metalloenzymes

So-called pre-distorted states accelerate photochemical reactions too

What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...

Im Focus: The first precise measurement of a single molecule's effective charge

For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.

Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...

Im Focus: Paradigm shift in Paris: Encouraging an holistic view of laser machining

At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.

No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...

Im Focus: Room-temperature multiferroic thin films and their properties

Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.

Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...

Im Focus: A thermometer for the oceans

Measurement of noble gases in Antarctic ice cores

The oceans are the largest global heat reservoir. As a result of man-made global warming, the temperature in the global climate system increases; around 90% of...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

10th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Münster, 10-11 April 2018

08.01.2018 | Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

 
Latest News

Gran Chaco: Biodiversity at High Risk

17.01.2018 | Ecology, The Environment and Conservation

Only an atom thick: Physicists succeed in measuring mechanical properties of 2D monolayer materials

17.01.2018 | Physics and Astronomy

Fraunhofer HHI receives AIS Technology Innovation Award 2018 for 3D Human Body Reconstruction

17.01.2018 | Awards Funding

VideoLinks
B2B-VideoLinks
More VideoLinks >>>