Historical tsunamis · Sep 18, 1984, 5:02 PM UTC
1984 Honshu Island tsunami
Japan
The tsunami of Sep 18, 1984, 5:02 PM UTC originated near Honshu Island (Japan).
Key facts
- Date
- Sep 18, 1984, 5:02 PM UTC
- Cause
- Earthquake
- Magnitude
- M6.9
- Depth
- 48 km
- Maximum documented water height
- 0.13 m
- Observation records
- 12
- Countries affected
- 1
It was triggered by a magnitude 6.9 earthquake at a depth of 48 km.
The highest documented water height was 0.13 m (Mera, Japan).
12 observation sites in 1 countries are recorded.
Map of observation sites
12Each dot is a documented observation site; colour and size show the observed water height. The triangle marks the source.
Observations by country
| Country | Observation records | Maximum documented water height | Deaths | Earliest arrival |
|---|---|---|---|---|
| Japan | 12 | 0.13 m Mera | — | — |
Highest documented water heights
12 / 12Individual documented observations for this event. Heights come from different measurement types and sources; not every location has a measured height.
| Location / station | Observed height | Distance from source | Country |
|---|---|---|---|
| Mera · Chiba | 0.13 m | 184 km | Japan |
| Miyako · Iwate | 0.11 m | 628 km | Japan |
| Yaene, Hachijo Island · Tokyo | 0.11 m | 190 km | Japan |
| Ishinomaki · Miyagi | 0.10 m | 490 km | Japan |
| Ayukawa · Miyagi | 0.09 m | 476 km | Japan |
| Hachinohe · Aomori | 0.09 m | 724 km | Japan |
| Ofunato · Iwate | 0.08 m | 556 km | Japan |
| Tosa-Shimizu · Kochi | 0.06 m | 806 km | Japan |
| Murotomisaki · Kochi | 0.04 m | 685 km | Japan |
| Onahama · Fukushima | 0.04 m | 329 km | Japan |
| Owase · Mie | 0.03 m | 489 km | Japan |
| Tateyama · Chiba | 0.03 m | 186 km | Japan |
More tsunamis
Source: NOAA National Centers for Environmental Information (NCEI), Global Historical Tsunami Database. Confirmed events only. Deaths and damage are database estimates; older records are incomplete. Water heights come from different types of observation.