1605 Keichō earthquake
| Local date | 3 February 1605 |
|---|---|
| Local time | 20:00 |
| Magnitude | 7.9 Ms |
| Epicenter | 33°30′N 138°30′E / 33.5°N 138.5°E |
| Fault | Nankai megathrust |
| Areas affected | Japan: Chūbu region, Kansai region, Shikoku, Kyushu |
| Tsunami | Yes |
| Casualties | Thousands |
The 1605 Keichō earthquake (Japanese: 慶長地震) occurred at about 20:00 local time on 3 February. It had an estimated magnitude of 7.9 on the surface-wave magnitude scale and triggered a devastating tsunami that resulted in thousands of deaths in the Nankai and Tōkai regions of Japan. It is uncertain whether there were two separate earthquakes separated by a short time interval or a single event. It is referred to as a tsunami earthquake, in that the size of the tsunami greatly exceeds that expected from the magnitude of the earthquake.