Historical tsunamis · Aug 8, 1993, 8:34 AM UTC
1993 Guam, Mariana Islands tsunami
USA Territory
The tsunami of Aug 8, 1993, 8:34 AM UTC originated near Guam, Mariana Islands (USA Territory).
Key facts
- Date
- Aug 8, 1993, 8:34 AM UTC
- Cause
- Earthquake
- Magnitude
- M7.8
- Depth
- 59 km
- Maximum documented water height
- 2.40 m
- Injuries
- 48
- Damage
- US$ 250 million
- Observation records
- 50
- Countries affected
- 5
It was triggered by a magnitude 7.8 earthquake at a depth of 59 km.
The highest documented water height was 2.40 m (Talofofo River, Guam, USA Territory).
50 observation sites in 5 countries are recorded.
Damage is estimated at US$ 250 million.
Map of observation sites
50Each dot is a documented observation site; colour and size show the observed water height. The triangle marks the source.
Tsunami arrival times
Documented arrival times from the NOAA/NCEI database, showing the earliest recorded location per country. Coverage is incomplete: a country without an entry was not necessarily spared.
- 0:00 hEarthquake (origin) · Aug 8, 1993, 8:34 AM UTC
- 0:05 hUSA Territory · Apra Harbor, Guam · 0.08 m
1 places with a documented arrival time
Observations by country
| Country | Observation records | Maximum documented water height | Deaths | Earliest arrival |
|---|---|---|---|---|
| USA Territory | 5 | 2.40 m Talofofo River, Guam | — | 0:05 h |
 Japan | 33 | 0.46 m Aburatsu | — | — |
 Taiwan | 2 | 0.15 m Hualien | — | — |
 United States | 9 | 0.14 m Shemya Island, Ak | — | — |
| Marshall Islands, Rep. Of | 1 | 0.07 m Kwajalein, Marshall Islands | — | — |
Highest documented water heights
15 / 50Individual 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 |
|---|---|---|---|
| Talofofo River, Guam · Gu | 2.40 m | 39 km | USA Territory |
| Ylig Bay, Guam · Gu | 1.80 m | 46 km | USA Territory |
| Aburatsu · Miyazaki | 0.46 m | 2,474 km | Japan |
| Mera · Chiba | 0.43 m | 2,481 km | Japan |
| Murotomisaki · Kochi | 0.43 m | 2,493 km | Japan |
| Tosa-Shimizu · Kochi | 0.38 m | 2,502 km | Japan |
| Chichijima Island · Bonin Is, Tokyo | 0.34 m | 1,586 km | Japan |
| Omaezaki · Shizuoka | 0.30 m | 2,486 km | Japan |
| Kushimoto · Wakayama | 0.24 m | 2,446 km | Japan |
| Owase · Mie | 0.23 m | 2,494 km | Japan |
| Ayukawa · Miyagi | 0.22 m | 2,824 km | Japan |
| Uragami · Wakayama | 0.21 m | 2,450 km | Japan |
| Shimizu · Shizuoka | 0.20 m | 2,522 km | Japan |
| Hanasaki · Hokkaido | 0.19 m | 3,359 km | Japan |
| Kochi · Kochi | 0.19 m | 2,548 km | Japan |
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.