A Major Disaster Is Imminent! A Massive Tsunami Up to 30 Meters High Could Send 200-Ton Boulders Flying… “Shocking Projected Damage” from the Ryukyu Trench Earthquake

Accumulating “Strain”

A series of eerie earthquakes has been occurring—

On May 20, a magnitude 5.9 earthquake struck off the coast of the main island of Okinawa, and strong shaking (Seismic Intensity 5+) was recorded on Yoron Island in Kagoshima Prefecture.On June 8, a magnitude 8.2 earthquake off the coast of Mindanao Island in the southern Philippines triggered a tsunami approximately 30 cm high that struck Miyazaki Port in Miyazaki Prefecture.

The government has identified two “high-risk zones” in the waters near Japan where the occurrence of another massive earthquake is considered imminent. Hiroki Kamata, an authority on earth sciences and professor emeritus at Kyoto University, explains (comments below are by Professor Kamata).

Damage Could Exceed That of the Great East Japan Earthquake

“These are the Kuril-Japan Trench off the coasts of Hokkaido and Tohoku, and the Nankai Trough, which extends from the Tokai region to the coast of Kyushu (see figure below). In both areas, it is believed that massive earthquakes with magnitudes exceeding M9—on par with or greater than the Great East Japan Earthquake—could occur.”

First, I would like to discuss the threat posed by the Kuril-Japan Trench, where earthquakes have been occurring frequently since the end of last year.

“Mega-earthquakes have occurred along the Kuril-Japan Trench at intervals of about 400 years. The last one, an earthquake of approximately magnitude 8.8, occurred between the 1610s and 1630s during the Edo period, triggering a tsunami nearly 30 meters high that reached 4 kilometers inland.According to a research group including Tohoku University, ‘strain’ is accumulating at a rate of 8 cm per year along the boundary between the North American Plate and the Pacific Plate. Considering this has been ongoing for 400 years, the accumulated ‘strain’ amounts to 32 meters. Since the plates may shift when they can no longer withstand the pressure, it would not be surprising if a massive earthquake were to occur at any time.”

According to projections released by the Cabinet Office, an earthquake in the Kuril Trench could result in up to 100,000 fatalities, while one in the Japan Trench could result in 199,000 fatalities.

The tsunami will arrive in 2 to 3 minutes

Next is the Nankai Trough mega-earthquake, for which the government estimates a probability of occurrence within the next 30 years of 60–90% or higher (20–50% according to a different calculation method).

“The tsunami striking the Pacific coast could reach a maximum height of 34 meters and, in some areas, hit the coast as early as 2 to 3 minutes after the quake occurs.The areas experiencing severe shaking of Seismic Intensity 7 will span nearly 150 municipalities across 10 prefectures, with approximately 2.35 million buildings completely destroyed or burned down. The death toll is estimated to be nearly 300,000. It is estimated that 68 million people—roughly half of Japan’s total population—will be affected.”

Mr. Kamata’s warnings about the potential for massive earthquakes are not limited to the Kuril-Japan Trench and the Nankai Trough. The Ryukyu Trench, which stretches 1,000 km from southern Kyushu to eastern Taiwan, also poses a significant danger.

“The Ryukyu Trench is also an epicenter for massive M9-class earthquakes. Although the exact recurrence interval is unknown due to a lack of data, it appears that massive tsunamis occur repeatedly—once every few hundred years—based on seafloor sediments and other evidence.

In 1771, during the mid-Edo period, a massive tsunami about 30 meters high, originating from the Ryukyu Trench, struck the Yaeyama Islands in Okinawa Prefecture, resulting in 12,000 deaths and missing persons. On Ishigaki Island, the central island of the Yaeyama archipelago, it is said that some villages were completely wiped out.Even today, numerous massive boulders weighing over 200 metric tons lie scattered along the east coast of Ishigaki Island. Known as “tsunami stones,” they are believed to have been carried up from the seafloor by past earthquakes in the Ryukyu Trench.”

In April 1924, a magnitude 7.7 earthquake occurred off the eastern coast of Taiwan. Eighteen people were killed, and more than 1,100 were injured. According to the government’s Earthquake Research Committee, there is a more than 90 percent probability that an earthquake of approximately magnitude 7 will occur near Yonaguni Island in Okinawa Prefecture within the next 30 years.

“The Ryukyu Trench is located at the boundary between the Eurasian Plate and the Philippine Sea Plate, just like the Nankai Trough. Although this is still in the research phase, it has been pointed out that there is a possibility it could trigger a massive trench-type earthquake in conjunction with the Nankai Trough. The damage would be incalculable.Furthermore, the area around the Okinawa Trough, located west of the Ryukyu Trench, is home to numerous active volcanoes, such as Iwo Jima. There is also a risk that volcanic activity could intensify if triggered by an earthquake.”

These three major trenches could be called “earthquake hotbeds.” The danger is imminent in each of them.

From the June 26–July 3, 2026, combined issue of *FRIDAY*