Reviewed by USGSAlaska11y ago
M2.7 earthquake 141 km SW of Nikolski, Alaska
Tuesday, August 25, 2015, 07:17:47 UTC · 52.169°N, 170.528°W
A magnitude 2.7 earthquake struck 141 km SW of Nikolski, Alaska on Tuesday, August 25, 2015, 07:17:47 UTC, at a depth of 32.7 km (shallow).
- Magnitude
- 2.7
- Minor · ml
- Depth
- 33 km
- Shallow
- Felt reports
- 0
- Max intensity I
- 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
84 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
33 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 9 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M4.6 on September 10, 2015. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
- 2.7Fox Islands, Aleutian Islands, Alaska11y ago · 20 km NE of this epicenter
- 2.7148 km SW of Nikolski, Alaska11y ago · 7 km W of this epicenter
- 2.8160 km SW of Nikolski, Alaska11y ago · 40 km S of this epicenter
- 4.6101 km SW of Nikolski, Alaska11y ago · 48 km E of this epicenter
- 2.6167 km WSW of Nikolski, Alaska11y ago · 30 km W of this epicenter
- 2.5117 km SW of Nikolski, Alaska11y ago · 25 km NE of this epicenter
- 2.9131 km SW of Nikolski, Alaska11y ago · 13 km N of this epicenter
- 4.5Fox Islands, Aleutian Islands, Alaska11y ago · 22 km N of this epicenter
Regional history
Past M5+ earthquakes within 300 km
USGS lists 760 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.8234 km SSW of Nikolski, AlaskaMarch 7, 1929 · 150 km S of this epicenter
- 7.881 km E of Nikolski, AlaskaJuly 2, 1965 · 215 km NE of this epicenter
- 7.4133 km WNW of Nikolski, AlaskaApril 18, 1916 · 142 km N of this epicenter
- 7.3Fox Islands, Aleutian Islands, AlaskaJune 24, 2011 · 90 km W of this epicenter
- 7.158 km WNW of Atka, AlaskaFebruary 28, 1970 · 300 km W of this epicenter
- 7.135 km SW of Nikolski, AlaskaMarch 11, 1957 · 108 km NE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 13 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1901M7.8
Aleutian Islands: Fox Islands
31 Dec 1901 · 87 km away
Limited damage (under $1M)tsunami
- 1965M6.5
Aleutian Islands: Fox Islands
2 Jul 1965 · 223 km away
Limited damage (under $1M)tsunami
- 1902M7.8
Aleutian Islands: Fox Islands
1 Jan 1902 · 208 km away
- 1907M7.8
Aleutian Islands
2 Sep 1907 · 72 km away
- 1929M7.8
Aleutian Islands: Fox Islands
7 Mar 1929 · 135 km away · intensity V
tsunami
- 1916M7.5
Aleutian Islands: Fox Islands
18 Apr 1916 · 131 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.