Almost all of the active volcanoes on Earth lie beneath miles of seawater at mid-ocean ridges, creating the long chain of volcanic mountains that encircles the Earth like the seam of a baseball. Scientists have long been puzzled by the observation that flows, erupted as white-hot lava at mid-ocean ridges, can be traced for several miles from their vents despite the fact that they erupt into seawater close to its freezing point. Now a group of scientists from academia and government believe they have the answer from lava samples collected using the deep-sea submersible ALVIN.
In the most recent issue of the magazine Nature, scientists from the U.S. Geological Survey (USGS) and an international group of university researchers report that the tops of the lavas chill against cold seawater protecting the molten interior, which moves forward on a thin film of vaporized seawater much like a hydrofoil. The seawater steam also bubbles through the lava and forms large cavities within the flowing, white hot material. Because of the high pressures, these cavities later collapse, producing a "swiss cheese" texture on the surface of the lava flow.
A critical piece of evidence came through very high magnification images of the insides of these cavities, using a sophisticated scanning electron microscope at the USGS in Denver, Colo. The images showed the presence of molten salt and many exotic minerals that could only have formed from vaporized seawater at very high temperatures.
Greenland ice flow likely to speed up: New data assert glaciers move over sediment, which gets more slippery as it gets wetter
17.08.2017 | Swansea University
Climate change: In their old age, trees still accumulate large quantities of carbon
17.08.2017 | Universität Hamburg
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,...
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...
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...
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...
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...
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