Experts: Japan still faces risk of aftershocks ten years after 3/11

People across Japan observed a moment of silence at 2:46 PM -- the exact time a magnitude 9.0 earthquake struck off the coast of Miyagi Prefecture on March 11, 2011.

A decade has passed since the disaster, but experts advising the Japanese government say the country still faces the risk of aftershocks.

Attendance at the government's annual memorial ceremony for victims of the disaster was limited due to the coronavirus pandemic. But Emperor Naruhito and Empress Masako were among those who took part. It was their first time attending since the Emperor ascended the throne in 2019. Last year's event was canceled due to the spread of the coronavirus.

"It is a matter of great importance, I believe, that we all keep ourselves united, and everlastingly maintain the will to stand by the afflicted people so that the progress of the reconstruction will steadily bear fruit," the Emperor said. "I, together with the Empress, would like to continue to listen to the voices of those in the afflicted regions."

Omi Chiharu gave a speech on behalf of survivors from Iwate Prefecture, one of the hardest-hit areas: "It's been 10 years since the disaster, yet the sadness we felt will never fade. We will protect the home we love and move toward the future."

People in Japan are mourning those who were killed 10 years ago, when a massive earthquake and tsunami struck northeastern Japan and triggered a nuclear catastrophe. A national memorial ceremony has been held in Tokyo.
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The earthquake triggered a tsunami that was over 10-meters high in parts and swept away hundreds of buildings. More than 15,900 people were killed and over 2,500 remain unaccounted for. 3,775 have since died of related causes.

The tsunami also knocked out electricity at Tokyo Electric Power Company's Fukushima Daiichi Nuclear Plant, causing one of the worst nuclear disasters in history. Radioactive substances contaminated the surrounding areas, and more than 35,000 people are unable to return home to this day.

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Preparing for the next disaster

On Tuesday, the government's Earthquake Research Committee published an assessment of seismic activity near the epicenter of the March 11 quake.

Experts says they recorded more than 5,300 tremors of magnitude 4 or greater in the area during the first year after the earthquake. In the year since last March, they logged 208. This marks a significant decline, but they say it is still more than the pre-disaster average for the area.

Last month, a magnitude 7.3 earthquake struck off the coast of Fukushima Prefecture, leaving about 150 people injured. Seismologists say it was a March 11 aftershock.

A M7.3 quake struck northeastern Japan on February 13.
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The committee says GPS monitoring shows that tectonic movements caused by the 2011 quake continue in much of Tohoku and eastern Japan. This means the regions will face the risk of large earthquakes or tsunamis for years to come.

"People should remember that they can't avoid the risk of a massive earthquake if they live in Japan," said Committee Chairperson Hirata Naoshi, an expert on disaster prevention measures. "We must keep calling on people to be prepared."