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Posts Tagged ‘megaquakes’

Is this the age of megaquakes?

April 19, 2011 1 comment

msn

Kyodo / Reuters

Buildings tossed together by the tsunami is seen in Miyagi Prefecture, northeastern Japan March 12, 2011. Scientists are asking if another megaquake will strike in the next six years.

By John Roach

First there was the earthquake and tsunami in Sumatra in 2004. Chile was shaken and lashed violently a year ago. Japan is still reeling from the twin disasters on March 11. It seems as if the Earth has woken from a long slumber and is violently re-jiggering its plates. Is there any truth to the notion?

The question of megaquake clustering, which I explored in the days following the 9.0 earthquake and tsunami in Japan, was a hot topic of conversation Thursday at the Seismological Society of America’s annual meeting in Memphis, Tenn., according to various media reports.

There, Charles Bufe, a seismologist retired from the U.S. Geological Survey in Denver, said the spate of recent megaquakes is very similar to a string of seven magnitude 8.5 or greater quakes that struck between 1950 and 1965. The intervening decades, he noted, were quiet.

Bufe and USGS colleague David Perkins analyzed the clustering and concluded that Read more…

The megaquake connection: Are huge earthquakes linked?

March 18, 2011 Comments off

newscientist.com

The recent cluster of huge quakes around the Pacific Ocean has fuelled speculation that they are seismically linked. New Scientist examines the evidence

A wave of activity (Image: Bernd Settnik/EPA/Corbis)

A wave of activity (Image: Bernd Settnik/EPA/Corbis)

AT 2.46 pm local time on Friday last week, Japan shook like never before. The magnitude 9.0 earthquake wrenched the main island of Honshu 2.5 metres closer to the US and nudged the tilt of Earth’s axis by 16 centimetres. At the epicentre, 130 kilometres offshore, the Pacific tectonic plate lurched westwards, and a 10-metre-high tsunami sped towards the coastal city of Sendai and the surrounding region.

The devastation caused by the events is difficult to exaggerate – estimates suggest the number of fatalities could top 10,000. One of the few consolations is that quakes of magnitude 8.5 and above are rare: the Sendai earthquake is in the top 10 of the highest-magnitude quakes of the last 100 years.

Yet three of these – the December 2004 Sumatra quake, the February 2010 Chile quake, and now Sendai – have struck in just over six years. This presents a horrifying possibility: Read more…