Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Two-billion-year-old Surprise Found Beneath The Azores

21.11.2002


Geologists may have to revise their ideas about what goes on in the Earth’s interior, following the publication today of new research in the journal ’Nature’. It appears that contrary to previous belief, part of the interior has remained undisturbed for at least two-and-a-half billion years, in spite of the massive forces at work inside the planet.



Like a saucepan of thick syrup being heated on the stove, huge convection currents within the Earth, generated by heat from the core, have stirred up the interior for most of its four-and-a-half billion year history. This has led geologists to believe that the interior is now well mixed. But Dr Simon Turner and Professor Chris Hawkesworth from the Earth Sciences Department at Bristol University, with colleagues at the Open University, have new data that suggest the presence of extremely ancient material beneath the Azores.

The islands of the Azores are volcanoes that sit either side of the Mid-Atlantic Ridge, a huge mountain chain beneath the ocean that formed as hot material from the Earth’’s interior rose to the surface. In some places, such as the Azores, the tops of these mountains form islands. The lavas from the Azores volcanoes appear to have been derived from some of the oldest material yet discovered within the convecting and well stirred part of the Earth.


One of the few ways to obtain information about the processes that go on in the Earth’’s interior is to analyse material that is brought up from these depths. The researchers therefore analysed the ratios of certain elements in the lavas that specifically characterise the source material they were derived from.

Dr Turner said: "The osmium ratios obtained in some of the Azores rocks are among the lowest ever seen in oceanic lavas. This indicates that the region from which the lavas were derived contained material that was left behind when continents were formed about two-and-a-half billion years ago. This depleted material was subsequently recycled back into the interior beneath the volcanic islands, where it has remained ever since."

The fact that such old material could reside in the Earth’’s interior for so long without being recycled will help inform new models about processes that go on inside the Earth.

Cherry Lewis | alfa
Further information:
http://www.bristol.ac.uk

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

Cholesterol-lowering drugs may fight infectious disease

22.08.2017 | Health and Medicine

Meter-sized single-crystal graphene growth becomes possible

22.08.2017 | Materials Sciences

Repairing damaged hearts with self-healing heart cells

22.08.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>