The 1946 Nankaido earthquake occurred in the Nankai Trough, a highly active, vigorous, subduction zone where large earthquakes have been recorded since the seventh century, with a recurrence time of 100 to 200 years.
The 1946 Nankaido earthquake occurred in the Nankai Trough, a convergent boundary where the Philippine Sea Plate is being subducted beneath the Eurasian Plate. Large earthquakes have been recorded along this zone since the seventh century, with a recurrence time of 100 to 200 years.