Reviewed by USGSAlaska1y ago
M3.2 earthquake 35 km WNW of Cold Bay, Alaska
Saturday, August 30, 2025, 06:35:43 UTC · 55.267°N, 163.257°W
A magnitude 3.2 earthquake struck 35 km WNW of Cold Bay, Alaska on Saturday, August 30, 2025, 06:35:43 UTC, at a depth of 198.2 km (intermediate).
- Magnitude
- 3.2
- Minor · ml
- Depth
- 198 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 earthquakeDashed circle: 50 km aftershock search area
In context
How big was it, and why here?
Energy released
951 kg of TNT
That is about 1/15,825 of the Hiroshima bomb. A magnitude 5.0 releases about 501 times more energy.
Tectonic setting
216 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
198 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 50 km
USGS lists 1 M2.5+ earthquake within 50 km in the following 30 days; the largest was M2.6 on September 2, 2025. 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 396 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.6The 1946 Unimak Island, Alaska EarthquakeApril 1, 1946 · 199 km S of this epicenter
- 7.82020 Perryville, Alaska EarthquakeJuly 22, 2020 · 297 km E of this epicenter
- 7.62020 Sand Point, Alaska EarthquakeOctober 19, 2020 · 243 km E of this epicenter
- 7.454 km SE of Sand Point, AlaskaMay 31, 1917 · 217 km E of this epicenter
- 7.32025 Sand Point, Alaska EarthquakeJuly 16, 2025 · 194 km SE of this epicenter
- 7.22023 Sand Point, Alaska EarthquakeJuly 16, 2023 · 187 km SE of this epicenter
- 7.190 km SE of King Cove, AlaskaMay 14, 1948 · 153 km SE of this epicenter
- 7.139 km S of Akutan, AlaskaMarch 22, 1957 · 232 km SW of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 11 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 169 recorded deaths. The most severe:
- 1946M8.6
Unimak Island
1 Apr 1946 · 199 km away · intensity VI
168 deaths$26 million damagetsunami
- 2023M7.2
Alaska Peninsula
16 Jul 2023 · 183 km away · intensity VI
1 deathtsunami
- 2020M7.8
Alaska
22 Jul 2020 · 297 km away · intensity VII
Limited damage (under $1M)tsunami
- 1788M8.0
Alaska Peninsula
6 Aug 1788 · 146 km away
tsunami
- 2020M7.6
Alaska
19 Oct 2020 · 243 km away · intensity IX
tsunami
- 1948M7.5
Alaska Peninsula
14 May 1948 · 168 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.