All the stocks rallied on the sales beats before easing off their gains in the U.S. indexes after news of a second large earthquake in Japan caused markets to sell off late Thursday morning.

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"It seems to reason that a large earthquake in one location could provide the extra force needed in another nearby location, to stretch that rubber band to the breaking point, thus triggering another earthquake, " Miller said.

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The March 11 earthquake and tsunami destroyed large parts of Japan's north-eastern coast, causing a nuclear crisis at the Fukushima power plant.

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It began as a low rumble, I thought it was a train or large machine on the road at first, but when the whole house began to shake I realised it could only be an earthquake or perhaps a large plane crash.

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Often, the people injured in a disaster are literally color-coded by medical workers with colored tags, says Carl Ramsay, chair of emergency medicine at Lenox Hill Hospital in Manhattan, who has cared for people after an earthquake, airplane crashes, and large-scale fires.

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The large Japanese automaker suffered the effects of the massive earthquake-cum-tsunami of early 2011, which disrupted its production and reduced its market share.

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The great Chicago fire in 1871 and the San Francisco earthquake and fire in 1906 were tides of destruction rolling for days across large, unfocused landscapes.

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Eastern Canada has a relatively low rate of earthquake activity, according to Natural Resources Canada, but there have been large earthquakes before, with about four exceeding magnitude 4 per year.

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The 9.0 earthquake that struck two years ago appears to have severely damaged the foundations of the plant - creating large cracks in the underground walls that are supposed to keep the plant water tight.

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