Tsunami ravages Japanese coast

As daylight breaks, survivors of a tsunami in Japan find that more than 20,000 of their friends and family have perished overnight.

The tsunami resulted from a disturbance in the Japan Trench, 120 miles east of Japan’s main island of Honshu. This deep underwater gorge is located where the Pacific tectonic plate is pushing under the Asian plate. A large earthquake at the fault caused a massive displacement of water.

In Kamaishi and along the Sanriku coast of Honshu, people were celebrating a yearly festival. Many felt the far-off quake, later estimated at a magnitude of 7.6, but most safely ignored the gentle rolling of the ground. However, about 20 minutes later, the harbor waters receded suddenly and, 15 minutes after that, an enormous tsunami crashed into the town’s coastline.

Waves may have reached as high as 115 feet in some places. Entire villages all along the coast were washed away during the evening. Fishermen who were working at sea and people living several miles inland, though, had no clue about the destruction until the following morning, when they arrived at the shore to find miles of the coast lined with wreckage and corpses. The final death toll was estimated at between 22,000 and 27,000 people.

This section of the Japanese coast seems vulnerable to such disasters. On March 3, 1933, 75-foot waves resulting from an 8.9-magnitude quake killed 3,000 people. Accounts also tell of destructive waves in 869 and 1611.

Approximately one third of all major earthquakes produce damaging tsunamis.