Reviewed by USGS121y ago
M8.3 earthquake 1906 Western Aleutian Islands (Hawadax/Rat Islands) Earthquake
Friday, August 17, 1906, 00:11:10 UTC · 51.853°N, 178.180°E
A magnitude 8.3 earthquake struck 1906 Western Aleutian Islands (Hawadax/Rat Islands) Earthquake on Friday, August 17, 1906, 00:11:10 UTC, at a depth of 110.0 km (intermediate). No earthquake of this size or larger appears within 300 km in the USGS catalog since 1900.
- Magnitude
- 8.3
- Great · mw
- Depth
- 110 km
- Intermediate
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- —
- No ShakeMap
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquake
In context
How big was it, and why here?
Energy released
43 megatons of TNT
That is about 2,823 times the Hiroshima bomb. It released about 89,125 times the energy of a magnitude 5.0.
Tectonic setting
131 km
from the nearest mapped plate boundary, between the North American and Pacific plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: intermediate
110 km
Intermediate-depth earthquakes usually break inside a plate that is sinking into the mantle. Shaking spreads over a wide area but is gentler at the epicenter than a shallow quake of the same size.
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 400 km
USGS has not published any M2.5+ earthquake within 400 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 3 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 2 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1906M8.3
Aleutian Islands: Rat Islands
17 Aug 1906 · 0 km away
- 1905M7.9
Andreanof Islands
14 Feb 1905 · 259 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.