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How Earthquakes Can Be Predicted: Researchers Reveal New Means
ScienceDaily (Dec. 1, 2010) — Researchers at the Hebrew University of Jerusalem who have been examining what happens in a "model earthquake" in their laboratory have discovered that basic assumptions about friction that have been accepted for hundreds of years are just wrong. Their findings provide a new means for replicating how earth ruptures develop and possibly enabling prediction of coming severe earthquakes.
See Also:
Earth & Climate
•Earthquakes
•Natural Disasters
•Tsunamis
•Earth Science
•Geology
•Near-Earth Object Impacts
Reference
•Elastic-rebound theory of earthquakes
•Alpine Fault
•North Anatolian Fault
•Earthquake liquefaction
"The findings have a wide variety of implications for materials science and engineering and could help researchers understand how earthquakes occur and how severely they may develop along a fault line," said Jay Fineberg, the Max Born Professor of Natural Philosophy at the Racah Institute of Physics at the Hebrew University.
The work by Fineberg, his graduate student Oded Ben-David and fellow researcher Gil Cohen, has been published in an article in Science.
For centuries, physicists have thought that the amount of force needed to push an object in order to make it slide across a surface is determined by a number called the coefficient of friction, which is the ratio between the forces pushing sideways and pushing down (basically, how much the object
Moon's Far Side Hoisted by Tides?
The mystery came into focus in the 1960s, when earthlings got their first good look at the moon's far side. Right away it was clear something was different: The far side is about six kilometers (3.7 miles) higher than the near side and it's a vast field of craters. There are none of the broad, dark, low-lying basins seen on the near side.
"Since then, we've come to understand that that area is high because the crust is thicker," explained Ian Garrick-Bethell, who recently moved from Brown University to the University of California at Santa Cruz.
The crust of the moon, like the crust of the Earth, is composed of less dense stuff than the rocks below it, so it "floats" on the surface, rather like an iceberg floats atop denser ocean water. The bigger the iceberg -- or in this case crust -- the greater the height it stands above water.
"No one's had a really good explanation for this crust," said Garrick-Bethell. So he and his colleagues looked back to the time when the moon was a blob of molten rock with a new, thickening crust to see how the simple tidal effects of the Earth affect the process.
Not too surprisingly, they found that the gravitational tug of the Earth would have caused the molten moon to bulge around the middle. That constant tug from Earth would have caused flexing and heating of the moon's crust and then-molten mantle.
Life on Mars Could Stem From Earth
If life on Mars is ever found, it may turn out to be less alien than you might expect. the artual is about stars and the other things in space. some people can also name stars with a card and u have to pay like is a car pay ment. news.discovery.com/space/mars-dna-earth-....html#mkcpgn=rssnws1
