Big quake risk said greater at Fukushima

The risk of strong earthquakes at the Fukushima nuclear plant increased after the magnitude-9 tremor that hit Japan last March, scientists report. A study using data from more than 6,000 earthquakes shows the March 11, 2011, tremor caused a seismic fault close to the nuclear plant to reactivate, a release from the European Geosciences Union said Tuesday. "There are a few active faults in the nuclear power plant area, and our results show the existence of similar structural anomalies under both the Iwaki and the Fukushima Daiichi areas," study leader Dapeng Zhao, a geophysics professor at Japan's Tohoku University, said. The number of earthquakes in Iwaki increased greatly after the March earthquake, he said. "Given that a large earthquake occurred in Iwaki not long ago, we think it is possible for a similarly strong earthquake to happen in Fukushima," Zhao said. The researchers say the finding should prompt authorities to strengthen the security of the Fukushima Daiichi nuclear power plant to withstand large earthquakes likely to occur in the region.