Japan commemorates the 13th anniversary of the 2011 earthquake and tsunami, a disaster that caused massive destruction and triggered the Fukushima nuclear meltdown. The country continues to rebuild, but scientists now warn of another potential catastrophe. Seismic activity in the Chishima Trench, off Hokkaido’s coast, suggests the possibility of a powerful earthquake in the near future.
Scientists Detect Troubling Signs Beneath the Ocean
A five-year study of the Chishima Trench, located about 150 kilometers (93 miles) offshore, has revealed alarming findings. Instead of gradually shifting, the tectonic plates beneath the trench appear to be locked together. If they suddenly break free, the energy released could trigger a devastating earthquake.
Researchers from the Japan Agency for Marine-Earth Science and Technology, Tohoku University, and Hokkaido University believe these plates have remained fused since the 17th century. A government study estimates a 7 to 40 percent chance of a magnitude-8.8 earthquake occurring in this trench within the next 30 years.
The Challenge of Predicting Earthquakes
Accurately predicting earthquakes remains difficult, according to experts. Fumiaki Tomita, an assistant professor at Tohoku University’s Research Center for the Prediction of Earthquakes and Volcanic Eruptions, explained the limitations of their research.
“Our task was to observe the current situation of the sea floor displacement off Hokkaido, but that does not allow us to discuss the possibility of an earthquake in the future,” Tomita said.
In 2019, scientists placed GPS monitoring devices on the seabed to track tectonic movements. Their findings confirmed that the plates are not gradually shifting as expected. Instead, they remain stuck. If they slip all at once, the resulting earthquake could be as strong as magnitude-8.8, shaking the region violently.
Remembering the 2011 Great East Japan Earthquake
Japan’s last megaquake, the 2011 Great East Japan Earthquake, remains the most powerful in the country’s history. The magnitude-9.0 earthquake struck 72 kilometers (45 miles) east of Miyagi prefecture, triggering a massive tsunami.
Waves as high as 40 meters (131 feet) surged inland, reaching up to 10 kilometers (6 miles) from the coast. The disaster claimed 19,759 lives, left 2,553 people missing, and led to the Fukushima nuclear plant meltdown—the worst nuclear crisis since Chernobyl.
The Risk of Another Deadly Earthquake
If an earthquake of magnitude-9.3 were to strike the Chishima Trench or the nearby Japan Trench, the consequences could be severe. Government projections estimate:
- 199,000 deaths
- More than 500,000 people displaced
- 220,000 buildings destroyed
- **Economic losses totaling ¥31.3 trillion ($211.
