Halfway to the center of the Earth, at the boundary between the core and the mantle, lies a massive folded slab of rock that once formed the ocean floor and sank beneath North America some 50 million years ago. A team of seismologists led by scientists at the University of California, Santa Cruz, detected the slab by analyzing seismic waves reflected from the deepest layer of the mantle beneath an area off the west coast of Central America.
"If you imagine cold honey pouring onto a plate, you would see ripples and folds as it piles up and spreads out, and thats what we think we are seeing at the base of the mantle," said Alex Hutko, a graduate student in Earth sciences at UCSC and first author of a paper describing the new findings in the May 18 issue of the journal Nature.
The discovery sheds new light on the processes that drive the movement of Earths tectonic plates. The planets outermost layer, or lithosphere, is broken into large, rigid plates composed of the crust and the outer layer of the mantle. New plate material is created at mid-oceanic ridges, where the ocean floor spreads apart, and old plate material is consumed in subduction zones, where one plate dives beneath another. But the fate of subducted lithosphere has been uncertain.
Tim Stephens | EurekAlert!
Mountain glaciers shrinking across the West
23.10.2017 | University of Washington
Climate change weakens Walker circulation
20.10.2017 | MARUM - Zentrum für Marine Umweltwissenschaften an der Universität Bremen
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...
23.10.2017 | Event News
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