August 10, 1968 Tsunami: N. Moluccas Islands, Indonesia
A tsunami caused by a magnitude 7.6 earthquake began at N. Moluccas Islands, Indonesia on August 10, 1968 at 02:07:04 UTC. The water rose as high as 0.4 meters. Its effects were recorded at 22 places.
Where the waves reached
The source (white) and every runup with a place, colored by the water height recorded there. A ring is a runup NCEI marks doubtful.
- Under 1 m
- 1 to 3 m
- 3 to 10 m
- 10 to 30 m
- 30 m and more
- Height not recorded
Travel times
How long the first wave took to reach each part of the ocean, one line for each hour up to 24, estimated from the source and the depth of the sea.
The travel times are computed in your browser, which needs JavaScript.
- 1 to 4 hours
- 5 to 6 hours
- 7 to 14 hours
- 15 hours and more
Computed in your browser the way NOAA’s own travel time maps are: the wave travels at the square root of gravity times the depth, over NOAA’s ETOPO1 depths averaged to a 10 arc-minute grid. Checked against NOAA NCEI’s maps for 21 tsunamis over the first 24 hours, these lines fall within 10 minutes of NCEI’s at half the points compared and within 52 minutes at 9 in 10. They give when the first wave could arrive, not how high it is; bays, harbors and island chains finer than the grid can see it later. Not for use in a warning: see tsunami.gov.
The tsunami
- Date
- August 10, 1968, 02:07:04 UTC
- Source
- N. Moluccas Islands, Indonesia
- Cause
- Earthquake
- Earthquake
- Magnitude 7.6, 25 km deep
- Maximum water height
- 0.4 m (1.3 ft)
- Runups recorded
- 22
- Tsunami intensity (Soloviev-Imamura)
- 1
- Tsunami magnitude (Iida)
- -1.3
- Waters
- Ocean
- How certain
- Definite tsunami
- Source location
- 1.400° N, 126.200° E
The toll
- Damage
- Limited (under about $1 million) with the earthquake or eruption that caused it
Where the literature gives no number, NCEI records a description on a scale of 1 to 4, printed here in its words. Damage is in millions of US dollars of the year of the event, not adjusted for inflation.
What the record says
NCEI’s account, from the sources it cites.
Reference #414:
August 10, 1968, 10:07 [local time], 2h07m03 UTC, 1.5 N., 126.2 E., depth 25 km; magnitude 7.8 MS, validity 4. There was a strong earthquake with source in the Maluku Sea. Slight damage was done at Manado. A tsunami arose. It was registered by tide gauges on the south coast of Japan, with a mean height of up to 14 cm and a maximal height of 40 cm at some capes. At this time the tide gauges on the eastern coast registered a swell 25-40 cm high, caused by a passing typhoon, and for this reason it is difficult to trace the tsunami on the records. The tsunami can hardly be detected on the records of the special automatic recorders set up on the islands of Enosliima (Miyagi Prefecture) and Oshima (off the Izu Peninsula), as well as of the portable tide gauge, temporarily in operation on Iwojima Island (Nampo Islands).
Every runup
Nearest the source first. Heights are above sea level at the time; a tide gauge reads half the wave’s full height.
| Where | Country | Km from source | Water height, m | Inland, m | Measured by | First wave, UTC | Deaths |
|---|---|---|---|---|---|---|---|
| Naze | Japan | 3,007 | 0.05 | Tide gauge (half the maximum wave height) | |||
| Iwojima Island (Nampo Islands) | Japan | 3,052 | Tide gauge (half the maximum wave height) | ||||
| Nishinoomote | Japan | 3,286 | 0.03 | Tide gauge (half the maximum wave height) | |||
| Aburatsu | Japan | 3,386 | 0.03 | Tide gauge (half the maximum wave height) | day 10, 06:40 | ||
| Hososhima | Japan | 3,483 | 0.02 | Tide gauge (half the maximum wave height) | |||
| Kamaegyoko | Japan | 3,527 | 0.08 | Tide gauge (half the maximum wave height) | |||
| Kamae | Japan | 3,528 | 0.1 | Tide gauge (half the maximum wave height) | day 10, 07:10 | ||
| Tosa-Shimizu | Japan | 3,545 | 0.09 | Tide gauge (half the maximum wave height) | day 10, 07:05 | ||
| Murotomisaki | Japan | 3,624 | 0.08 | Tide gauge (half the maximum wave height) | day 10, 07:02 | ||
| Kochi | Japan | 3,641 | Tide gauge (half the maximum wave height) | ||||
| Kushimoto | Japan | 3,688 | 0.1 | Tide gauge (half the maximum wave height) | day 10, 07:02 | ||
| Shirahama | Japan | 3,699 | 0.03 | Tide gauge (half the maximum wave height) | |||
| Uragami | Japan | 3,700 | 0.2 | Tide gauge (half the maximum wave height) | |||
| Owase | Japan | 3,765 | 0.1 | Tide gauge (half the maximum wave height) | day 10, 07:28 | ||
| Owase | Japan | 3,765 | 0.11 | Tide gauge (half the maximum wave height) | |||
| Toba | Japan | 3,825 | 0.03 | Tide gauge (half the maximum wave height) | |||
| Omaezaki | Japan | 3,883 | 0.11 | Tide gauge (half the maximum wave height) | |||
| Nagashima | Japan | 3,885 | 0.08 | Tide gauge (half the maximum wave height) | day 10, 07:40 | ||
| Minami-Izu | Japan | 3,906 | 0.09 | Tide gauge (half the maximum wave height) | |||
| Oshima | Japan | 3,933 | Tide gauge (half the maximum wave height) | ||||
| Enoshima | Japan | 4,388 | Tide gauge (half the maximum wave height) | ||||
| Urakami | Japan | 4,811 | 0.2 | Tide gauge (half the maximum wave height) | day 10, 07:12 |
More
Every tsunami in 1968The 1900sTsunamis of IndonesiaThe earthquakeThis day in weather historyAlerts in force
Sources
Tsunami events and runups from NOAA’s National Centers for Environmental Information, Global Historical Hazard Database, cited as NCEI/WDS, doi:10.7289/V5PN93H7. Public domain. Read 2026-09-24. NCEI tsunami event 2006.