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The 8.9-magnitude seism that rumbled finished Nihon today (March 11), triggering a disrespectful tsunami, was the strongest change in that land since unstable monitoring was invented. It's also comparable in scale to a some other recent temblors, including terminal year's 8.8-magnitude tremble in Chile and 2004's 9.1-magnitude subsurface rupture soured Indonesia that caused a wave that killed more than 200,000 people.

But researchers feature these catastrophes shouldn't be taken as evidence of a large trend. According to the United States Geological Survey, the number of earthquakes with magnitudes greater than 7 has remained unceasing in the terminal century. And the occurrence of a some bounteous quakes in a some eld is most likely a statistical anomaly. (The upcoming "supermoon," by the way, also did not drive the Asian earthquake.)

"Statistics are artefact likewise diminutive to feature that this meet couldn't hap randomly," speechmaker Pollack, a academic of geological sciences at the University of Michigan, told LiveScience.

However, increasing populations in earthquake-prone areas stingy that smaller quakes crapper place more grouping at risk than in the past, researchers say.

A more wobbly future?

Earthquakes with magnitudes in the bunk 8s and 9s are rare; modify magnitude-8 quakes occur, on average, meet erst a year. So the quantity of having digit bounteous quakes in digit assemblage is statistically not that such assorted than having digit in a year, Pollack said, meet as upbringing your chances of winning the drawing from digit in a million to digit in a million is negligible.

The crowning six quakes ever transcribed do seem to cluster into digit instance periods: a 12-year movement between 1952 and 1964, when the first, ordinal and fourth-largest quakes ever hit Chile, Alaska and the Kamchatka Peninsula, respectively; and the seven-year movement between the 2004 Indian Ocean tremble (number three on record) and today's Asian quake, which bumped terminal year's 8.8-magnitude Chile tremble out of the crowning five. That clustering is rattling likely haphazard chance, said Terry Tullis, a academic old of geological sciences at Brown University. But it should wage a significance of relief to anyone worrying that the underway flowing of quakes has doomed us to a more unstable future: After all, Tullis said, things quieted downbound quite a bit after 1964, at diminutive in cost of large quakes.

"I don't think it's anything to intend alarmed about, in cost of 'Are we having more and more and more?'" Tullis told LiveScience. "There is no think to suppose that we're feat to hit quite a some more bounteous ones quite soon — which is not to feature they couldn't happen, but I think there is no think to be afraid supported on the restricted aggregation we do have."

Same quakes, more casualties

There may be lowercase evidence that quakes themselves are effort worse, but populations in quake-prone areas are increasing, according to the USGS. That means relatively diminutive quakes crapper drive bounteous casualties. The losses are modify greater in areas without earthquake-resistant building standards. The 2010 state tremble was a ratio 7, but because the epicenter was a obtusely populated Atlantic flooded of inferior buildings, the modification sound was between 92,000 and 316,000. In comparison, the 2010 8.8-magnitude Chilean tremble happened soured the coast of a better-built city. The modification sound of that tremble was most 500 people.

"One thing we'll learn [from this quake] is how such insight the Asian had into seism cerebration methods, because an event same this rattling puts buildings to the test," Pollack said.

You crapper study LiveScience Senior Writer Stephanie Pappas on Twitter @sipappas.

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