[1] The earthquake measured between 8.1 and 8.4 on the moment magnitude scale, and was felt from Northern Honshū to Kyūshū.

It occurred almost two years after the 1944 Tōnankai earthquake, which ruptured the adjacent part of the Nankai megathrust.

Large earthquakes have been recorded along this zone since the 7th century, with a recurrence time of 100 to 200 years.

Scientists propose that this seamount might work as a barrier inhibiting brittle seismogenic rupture.

[4] The earthquake caused extensive damage, destroying 36,000 homes in southern Honshū alone.