"Identical to the Great East Japan Earthquake" Japan Warned of Large-Scale Earthquake

Warnings are emerging in Japan of a large-scale earthquake that could cause around 200,000 deaths. It has been pointed out that this is not merely a consequence of trauma from the Great East Japan Earthquake, but is actually based on research findings. This research predicts the worst-case scenario that could occur if a large-scale earthquake strikes.

In a paper published this year, a joint research team from Tohoku University, Hokkaido University, and JAMSTEC (equivalent to Korea's Institute of Ocean Science and Technology) proposed a theory of large-scale earthquake cycles. The research findings were published in 'Communications Earth & Environment,' a sister journal of the prestigious scientific journal Nature. The research team confirmed records indicating that a massive earthquake with a magnitude of 8.8 to 9.2 occurred between 1611 and 1630, and that a tsunami reached 4 km inland at that time.

The basis for such large-scale earthquakes is the fact that the Pacific Plate collides with the Sanriku coast of Japan at a rate of 8 cm per year. Calculating the amount this plate has moved over the past 400 years shows an accumulated deformation of approximately 30 meters. Considering that the fault slipped by about 25 meters during the past magnitude 8.8 earthquake, it is evident that the currently accumulated energy is substantial.

Results from drilling investigations in Lake Harutori, a freshwater lake located inland on Hokkaido Island, also support the periodicity of large-scale earthquakes and tsunamis. Analysis of drilled sediments revealed multiple layers of yellowish marine sediments on the lakebed. These are traces of seawater pushed into the freshwater lake and deposited, providing clear evidence that large-scale tsunamis have occurred periodically in the past.

Areas where earthquakes should occur but have not for a long time are called 'locked fault segments' or 'seismic gaps'. Such areas should not be taken lightly, as energy continues to accumulate, increasing the probability of even larger earthquakes in the future. In fact, during the Great East Japan Earthquake, a supermassive earthquake occurred in a seismic gap that had not experienced an earthquake for a long time.

The Japanese government's disaster prevention philosophy is to predict the worst-case disaster scenario and formulate policies accordingly. This is not intended to frighten the public, but rather a proactive measure to minimize damage in the event of a disaster. For example, without any preparation, 200,000 deaths are expected, but with thorough preparation, the number of deaths can be reduced to 30,000. Specifically, they are setting concrete goals and preparing, such as stocking warm clothing to ensure zero deaths from cold exposure during a winter earthquake.