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 NASA examines Peru's deadly rainfall
24.03.2017 | NASA/Goddard Space Flight Center

nachricht Steep rise of the Bernese Alps
24.03.2017 | Universität Bern

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Argon is not the 'dope' for metallic hydrogen

24.03.2017 | Materials Sciences

Astronomers find unexpected, dust-obscured star formation in distant galaxy

24.03.2017 | Physics and Astronomy

Gravitational wave kicks monster black hole out of galactic core

24.03.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>