Reviewed by USGSAlaska5y ago
M2.7 earthquake 134 km SSE of Sand Point, Alaska
Monday, July 5, 2021, 02:22:14 UTC · 54.235°N, 159.652°W
A magnitude 2.7 earthquake struck 134 km SSE of Sand Point, Alaska on Monday, July 5, 2021, 02:22:14 UTC, at a depth of 29.6 km (shallow).
- Magnitude
- 2.7
- Minor · ml
- Depth
- 30 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: 50 km aftershock search area
In context
How big was it, and why here?
Energy released
169 kg of TNT
That is about 1/88,990 of the Hiroshima bomb. A magnitude 5.0 releases about 2,818 times more energy.
Tectonic setting
45 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
30 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 50 km
USGS lists 15 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M4.0 on July 6, 2021. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
- 3.3107 km SSE of Sand Point, Alaska5y ago · 29 km N of this epicenter
- 2.6107 km SSE of Sand Point, Alaska5y ago · 27 km N of this epicenter
- 3.095 km SSE of Sand Point, Alaska5y ago · 40 km N of this epicenter
- 2.6115 km SSE of Sand Point, Alaska5y ago · 21 km N of this epicenter
- 2.8123 km SSE of Sand Point, Alaska5y ago · 11 km N of this epicenter
- 2.791 km SSE of Sand Point, Alaska5y ago · 43 km N of this epicenter
- 2.794 km SSE of Sand Point, Alaska5y ago · 40 km N of this epicenter
- 3.3100 km SSE of Sand Point, Alaska5y ago · 34 km N of this epicenter
Regional history
Past M5+ earthquakes within 300 km
USGS lists 351 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 · 224 km W of this epicenter
- 8.21938 Semidi Islands, Alaska EarthquakeNovember 10, 1938 · 141 km NE of this epicenter
- 7.82020 Perryville, Alaska EarthquakeJuly 22, 2020 · 115 km NE of this epicenter
- 7.62020 Sand Point, Alaska EarthquakeOctober 19, 2020 · 41 km N of this epicenter
- 7.454 km SE of Sand Point, AlaskaMay 31, 1917 · 86 km N of this epicenter
- 7.190 km SE of King Cove, AlaskaMay 14, 1948 · 105 km NW of this epicenter
- 7.0113 km ESE of Chignik, AlaskaMay 4, 1923 · 256 km NE 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, which together caused about 168 recorded deaths. The most severe:
- 1946M8.6
Unimak Island
1 Apr 1946 · 224 km away · intensity VI
168 deaths$26 million damagetsunami
- 2020M7.8
Alaska
22 Jul 2020 · 115 km away · intensity VII
Limited damage (under $1M)tsunami
- 1938M8.2
Alaska
10 Nov 1938 · 161 km away · intensity VI
tsunami
- 2021M8.2
Alaska Peninsula
29 Jul 2021 · 168 km away · intensity VIII
tsunami
- 1788M8.0
Alaska Peninsula
6 Aug 1788 · 122 km away
tsunami
- 2020M7.6
Alaska
19 Oct 2020 · 41 km away · intensity IX
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.