May 15, 1868 Tsunami: Shumagin Islands, AK, United States
A tsunami caused by an earthquake began at Shumagin Islands, AK, United States on May 15, 1868. The water rose as high as 6.1 meters. Its effects were recorded at 1 place.
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
- May 15, 1868
- Source
- Shumagin Islands, AK, United States
- Cause
- Earthquake
- Earthquake
- The earthquake
- Maximum water height
- 6.1 m (20.0 ft)
- Runups recorded
- 1
- Tsunami intensity (Soloviev-Imamura)
- 2.5
- Waters
- Ocean
- How certain
- Questionable tsunami
- Source location
- 55.000° N, 161.000° W
The toll
The record gives no deaths, injuries or damage for this tsunami.
What the record says
NCEI’s account, from the sources it cites.
There is a report of a slight earthquake in Unga Island, during which the water in the port on the northern side of the island was agitated. The report states that "the level rose 6 meters," but does not clarify if this is the height of a wave, the height of a runup, or the uplift of land. It is unlikely that it refers to uplift or wave height given the size of the earthquake; possibly, a local landslide caused a runup of 6 meters. Another possibility is that this is a confused report, combining a small local earthquake with a Kodiak runup produced by the great Arica, Peru (now Chile) earthquake of August 14, 1868. (Ref #239)
1868, May 15. There was an earthquake on the Alaskan Peninsula. During this earthquake, the water in the port on the northern side of Ungla Island was very agitated. At some places, the level rose 6 m (20 feet) (Reference #414).
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 |
|---|---|---|---|---|---|---|---|
| Unga Island, AK, AK doubtful | United States | 35 | 6.1 | Eyewitness observation of water height |
More
Every tsunami in 1868The 1800sTsunamis of United StatesThe 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 975.