科学家担忧日本会发生更多大地震

"They are thinking of the possibility you could have a magnitude eight, which makes sense. The largest aftershocks of an earthquake over the years around the world we've observed tend to be about one magnitude unit less than the main shock, more likely within months, but it could be years."

“他们在考虑发生八级地震的可能性，这也是有道理的。我们所观测到的世界上地震发生后强度最大的余震通常要比主震小一级，一般是在几个月内发生，但也可能是在几年后。”

Professor Sagiya of Nagoya University says the March 11 quake also “activated” inland faults.

名古屋大学的鹭谷威教授说，3-11大地震还“激活”了内陆的断层。

"They may be not as large as magnitude eight, but because they occur just beneath our cities, our house, they can be quite disastrous," said Sagiya.

“它们可能不会有八级那么大，但是因为地震就在我们城市、房屋下面发生，这些地震将会是灾难性的。”

Professor Stein - a former editor of the Journal of Geophysical Research - agrees that as a result of the March 11 temblor - the fourth most powerful ever recorded - the quake risk has increased for Japan, one of the world’s most seismically active places.

西北大学的斯坦认为，鉴于3-11大地震是有记载以来的第四大地震，日本发生更多地震的危险增加。日本是世界上发生地震最频繁的国家。

"We sometimes use this analogy of a kid's game called 'booby trap' where you have a bunch of little blocks and there's a spring piston and it pushes on them. And, once you disturb one piece then you increase the possibility that the other pieces are going to be pushed and slip also," said Stein. "So if you think of Japan in that way you can realize that once you've had a huge earthquake of this sort there's a chance that a lot of faults could have smaller earthquakes."

他说，“我们有时候把地震和小孩子们玩的一种叫做‘陷阱’的游戏做比较。你有一些小砖块和一个活塞弹簧，弹簧挤着砖块。如果你推动一块砖，那么其它砖块被挤压和交错的机会也就增加了。因此如果你把日本想象成那样的话，你就会发现在这么大一场地震发生后，其它断层上发生很多较小地震的可能性就会存在。”

Seismologists caution the public that their work is still an inexact science. They note improvements for indicating where a big quake approximately will occur, but not when.

地震学家提醒公众，他们的研究仍然无法十分精确。他们表示，在预测大地震有可能发生的位置方面有了一些进步，但他们仍然不能预测地震发生的时间。

They also acknowledge that this year’s huge magnitude 9.0 was not anticipated, looking at the historical data.

地震学家还承认，通过研究历史数据他们并没有预期日本今年会发生这次大地震。

That was also the case with the December 2004 earthquake off western Indonesia, which measured magnitude 9.3.

同样，2004年12月印度尼西亚以西海域发生的9.3级大地震也没有被预测到。

That prompted seismologists and geologists to re-examine the world’s subduction zones, areas where oceanic plates slide beneath either a continental plate or another oceanic plate.

这就使地震学家和地质学家重新对世界隐没带进行研究。隐没带是指一个大洋板块沉入到一个大陆板块或另一个大洋板块而形成的聚合板块边缘区域。

Some of the researchers, analyzing fresh data, are now challenging the conventional thinking and willing to state that most, if not all, of the world’s subduction zones (more than a dozen are recognized) are able to generate quakes equal to or exceeding magnitude 9.0.

一些学者通过对新数据的分析后对传统理论提出挑战。他们指出，世界上绝大多数隐没带都可以产生九级或九级以上的地震。