AccuWeather.com

By John Marsh, AccuWeather.com Staff Writer

Feb 16, 2012; 2:55 PM ET

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This Nov. 12, 2011 photo shows a view of the crippled Fukushima Daiichi nuclear power plant in Okuma town, Japan. Japan said Friday, Dec. 6, 2012 it will soon require atomic reactors to be shut down after 40 years of use to improve safety following the nuclear crisis set off by the March 11, 2011 tsunami. Concern about aging reactors has been growing because the three units at the Fukushima Dai-ichi plant that went into meltdown after the tsunami were built starting in 1967. (AP Photo/David Guttenfelde)

A 5.2-magnitude earthquake has struck near the eastern coast of Honshu, Japan. This quake occurred at 7:34 a.m local time on Wednesday, Feb. 5.

The quake occurred quickly after the release of a new study revealing that there is an increased earthquake risk for the Fukushima Daiichi Nuclear Power Plant.

The magnitude 9 earthquake that struck Japan on March 11, 2011, has reactivated a seismic fault close to the Fukushima plant, according to a report released by the European Geosciences Union.

"They're on the ring of fire, the area around the Pacific Ocean that has active volcanoes and is quite active in terms of its faultiness," AccuWeather.com Senior Meteorologist Mike Pigott said. "It's always been historically active. There's been a recent concentration of earthquake activity. When you have a big quake like that (referring to last March), you're not just going to see aftershocks for days, weeks or months. They can potentially last for years as the fault tries to re-settle."

Map of Japan's islands indicating the area of study (black box). The purple star marks the epicentre of the March 11 earthquake and the red star the Iwaki epicentre. Fukushima Daiichi is highlighted by a red square. Black triangles indicate active volcanoes. Numbers on the side of the image represent latitude and longitude. Credit: Ping Tong, Dapeng Zhao and Dinghui Yang.

In April 2011, a magnitude 7 earthquake was recorded as the strongest aftershock of the large quake from the previous month with an inland epicenter. The quake struck Iwaki, Japan, which is 60 km (roughly 37 miles) southwest of the Fukushima plant. The Iwaki quake was caused by "fluids moving upwards from the subjecting Pacific plate to the crust," according to the European Geosciences Union.

"Essentially, that's from the plate being submerged in water," said Pigott. "As the plates move, rock begins to melt and water gets hotter and boils. The water then becomes highly pressurized. Then the liquid wants to move upwards, so it moves the plate up. Think of it like a hydraulic piston."

Ping Tong, lead author of the report, said, "Ascending fluids can reduce the friction of part of an active fault and so trigger it to cause a large earthquake. This, together with the stress variations caused by the 11 March event, is what set off the Iwaki tremor."

The report also stated that a tremor could occur in the future and be much closer to the Fukushima plant. Scientists state that ascending fluid levels in the area may indicate that another quake is likely to occur some time in the near future.

Near Iwaki, Japan's seismic network has recorded over 24,000 detected tremors from march through October of 2011. The previous nine years, there had only been 1,300 detected quakes in total.

Scientists contributing to the report have warned that heightened security to withstand large quakes should be provided to the Fukushima plant in the event of another high magnitude earthquake.

Information in this story was provided by the European Geosciences Union.