Reviewed by USGSAlaska89y ago
M5.9 earthquake 124 km SSW of Akhiok, Alaska
Friday, November 11, 1938, 08:30:54 UTC · 55.920°N, 154.986°W
A magnitude 5.9 earthquake struck 124 km SSW of Akhiok, Alaska on Friday, November 11, 1938, 08:30:54 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M6.6 on November 11, 1938.
- Magnitude
- 5.9
- Moderate · mw
- Depth
- 15 km
- Shallow
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- —
- No ShakeMap
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquakeDashed circle: 75 km aftershock search area
In context
How big was it, and why here?
Energy released
11 kilotons of TNT
That is about the energy of the Hiroshima bomb. It released about 23 times the energy of a magnitude 5.0.
Tectonic setting
91 km
from the nearest mapped plate boundary, between the North American and Pacific plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
15 km
Shallow earthquakes (under 70 km) produce the strongest surface shaking for their size, so they are the ones most likely to cause damage near the epicenter.
Did You Feel It?
Where it was felt
No “Did You Feel It?” reports have been published for this event yet. If you felt it, you can add your report on the USGS website.
I felt it — report to USGS ↗USGS PAGER estimate
Who was exposed to shaking
USGS publishes PAGER impact estimates for significant earthquakes, usually within an hour. No PAGER estimate is available for this event.
After the main event
Aftershocks within 75 km
USGS lists 1 M2.5+ earthquake within 75 km in the following 30 days; the largest was M6.1 on November 11, 1938. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 66 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.21938 Semidi Islands, Alaska EarthquakeNovember 10, 1938 · 217 km W of this epicenter
- 7.9Kodiak Island region, AlaskaOctober 9, 1900 · 294 km NE of this epicenter
- 7.14 km ENE of Karluk, AlaskaNovember 7, 1912 · 189 km N of this epicenter
- 7.0113 km ESE of Chignik, AlaskaMay 4, 1923 · 112 km W of this epicenter
- 6.8Event 48 Novarupta-Mount Katmai area, Alaska PeninsulaJune 10, 1912 · 262 km N of this epicenter
- 6.6128 km SE of Chignik, AlaskaJuly 28, 1934 · 114 km W of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 9 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1900M8.3
Kodiak Island
9 Oct 1900 · 160 km away · intensity VIII
Limited damage (under $1M)
- 1788M8.0
Unga Island
21 Jul 1788 · 171 km away · intensity VII
Limited damage (under $1M)tsunami
- 1792
Kodiak Island
1792 · 219 km away · intensity VII
Limited damage (under $1M)tsunami
- 1938M8.2
Alaska
10 Nov 1938 · 218 km away · intensity VI
tsunami
- 1906M7.6
Aleutian Islands
23 Dec 1906 · 123 km away
- 1912M7.5
Alaska Peninsula
7 Nov 1912 · 176 km away · intensity V
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.