【2】 Previous Nankai Earthquakes

The Nankai Earthquake Repeats!

   Historically, the Nankai Earthquake occurs every 100 to 150 years. The most recent occurrence was in 1946. The scale of this earthquake was quite small, meaning there is still a great deal of stress left to be released. As a result, there is a strong likelihood the fault-line will not wait the usual 100 years, and the next earthquake can be expected in the first half of this century.
   The Nankai Earthquake has occurred almost concurrently with the nearby Tonankai Earthquake. There is a strong connection between the two seismic events. As a rule, the Nankai Earthquake features both large tremors and a tsunami. However, the 1605 Keicho-era Nankai Earthquake was small, yet still caused a very damaging Tsunami.

The 1946 Nankai Earthquake

   The previous Nankai Earthquake occurred on December 21st 1946 at 4:19am. The epicenter was on the sea floor 50km off the coast of Cape Shiono in Wakayama, and caused massive damage throughout Kochi and western Japan. The earthquake was of magnitude 8.0.
   Kochi suffered large tremors, and coastal areas were inundated by waves of 4~6 meters. Sadly, 679 people lost their lives, and 1836 were injured. 4846 buildings collapsed or were washed away.