Earthquake · reviewed by a seismologist
M 3.5ml
198 km SE of Perryville, Alaska
- When
- Magnitude
- M 3.5 (ml)
- Depth
- 33 km below the surface
- Felt
- no reports yet
- Measured shaking
- intensity I (ShakeMap)
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 5 hours ago
A magnitude 3.5 earthquake was recorded 198 km SE of Perryville, Alaska at 20:34 UTC on 2026-10-06. This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.
How big was it?
This earthquake released about 2.7 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.5 would have released about 32 times as much.
- Northridge, California 1994 M 6.7 63,000× the energy of this one
- Mineral, Virginia 2011 M 5.8 2,800× the energy of this one
- Magna, Utah 2020 M 5.7 2,000× the energy of this one
- This earthquake M 3.5 about 2.7 tons of TNT
- Around the size people start to feel M 3.0 this one released 5.6× 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 5.6 on 2021-09-16 — about 1,400 times the energy of this one.
Before 2016, the USGS record lists 7 earthquakes of M5 or more within 50 km; the five largest:
- 6.2 189 km SE of Chignik, Alaska · 33 km NE of this epicentre
- 5.9 182 km SE of Perryville, Alaska · 33 km WSW of this epicentre
- 5.6 205 km SE of Chignik, Alaska · 43 km ENE of this epicentre
- 5.5 160 km SE of Perryville, Alaska · 38 km NW of this epicentre
- 5.0 176 km SSE of Chignik, Alaska · 27 km N 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 54.7110, -156.8320. Map © OpenStreetMap contributors.
Aftershocks so far
No further earthquakes have been recorded within 50 km since this one.
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.
Revisions
USGS refines a solution as more stations report. Every change we have seen is listed here.
| What changed | From | To | When |
|---|---|---|---|
| review status | automatic | reviewed | |
| location | 202 km SE of Perryville, Alaska | 198 km SE of Perryville, Alaska | |
| longitude | -156.79 | -156.83 | |
| latitude | 54.68 | 54.71 | |
| depth | 20.8 | 32.8 | |
| measured intensity | not reported | 1 | |
| location | 197 km SE of Perryville, Alaska | 202 km SE of Perryville, Alaska | |
| longitude | -156.85 | -156.79 | |
| latitude | 54.72 | 54.68 | |
| depth | 29.1 | 20.8 | |
| magnitude | 3.4 | 3.5 | |
| location | 191 km SE of Perryville, Alaska | 197 km SE of Perryville, Alaska |
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.