Earthquake · reviewed by a seismologist
M 4.3mwr
100 km N of Yakutat, Alaska
Yes. A magnitude 4.3 earthquake was recorded 100 km N of Yakutat, Alaska at 01:56 UTC on 2025-12-07, 5.0 km deep.
- When
- Magnitude
- M 4.3 (mwr)
- Depth
- 5.0 km below the surface
- Felt
- no reports yet
- Measured shaking
- intensity V (ShakeMap)
- USGS impact alert
- green
- Tsunami
- USGS flagged this event for tsunami evaluation. Follow tsunami.gov for official messages.
- Nearest
- Yakutat City and Borough, 65 km SW
- Nearest mapped fault
- Fairweather fault system, 16 km from its surface trace — near is not the same as on
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 254 days ago
This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon.
At this magnitude and depth, people at rest would likely notice it out to about 121 km (75 mi) from the epicentre. Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.
How big was it?
This earthquake released about 43 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.3 would have released about 32 times as much.
- Northridge, California 1994 M 6.7 4,000× the energy of this one
- Mineral, Virginia 2011 M 5.8 180× the energy of this one
- Magna, Utah 2020 M 5.7 130× the energy of this one
- This earthquake M 4.3 about 43 tons of TNT
- Around the size people start to feel M 3.0 this one released 89× more
Energy from the Gutenberg–Richter relation (log10E = 1.5M + 4.8), rounded to two figures; bar length is magnitude, which is already a logarithm of energy. Magnitudes of past earthquakes from the USGS catalogue.
For this area
The largest earthquake within 50 km since 2016 was M 7.0 on 2025-12-06 — about 11,000 times the energy of this one.
Before 2016, the USGS record lists 4 earthquakes of M5 or more within 50 km:
- 6.0 90 km NNW of Yakutat, Alaska · 43 km WSW of this epicentre
- 5.4 65 km NNE of Yakutat, Alaska · 41 km SSE of this epicentre
- 5.0 66 km NNE of Yakutat, Alaska · 40 km SSE of this epicentre
- 5.0 92 km NNW of Yakutat, Alaska · 41 km WSW of this epicentre
Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.
Where
Epicentre 60.4444, -139.6120. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Yakutat City and Borough, AK | 65 km (40 mi) | SW | earthquakes near Yakutat City and Borough |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
60 earthquakes have been recorded within 50 km since this one.
- 2.5 111 km N of Yakutat, Alaska
- 2.5 105 km N of Yakutat, Alaska
- 2.5 115 km N of Yakutat, Alaska
- 3.3 97 km N of Yakutat, Alaska
- 2.6 104 km N of Yakutat, Alaska
- 2.8 101 km N of Yakutat, Alaska
- 3.3 115 km N of Yakutat, Alaska
- 2.7 112 km N of Yakutat, Alaska
- 3.9 120 km N of Yakutat, Alaska
- 2.3 101 km N of Yakutat, Alaska
- 3.0 98 km N of Yakutat, Alaska
- 3.1 103 km N of Yakutat, Alaska
- 3.6 111 km N of Yakutat, Alaska
- 3.4 98 km N of Yakutat, Alaska
- 3.1 115 km N of Yakutat, Alaska
Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of . QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.
On USGS
- The official USGS event page — the source of record for every value above
- Did you feel it? Report it to USGS — reports go to USGS, not to us
- ShakeMap for this event, when USGS has produced one
QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.