QuakeIndex

Earthquake · automatic estimate, may change

M 2.5ml

60 km SSE of Perryville, Alaska

· 28 km deep · released about 170 lb of TNT

10 km30 km60 km120 km N
Distance rings around the epicentre, with the nearest towns at their true direction. Not a shaking map — see the USGS ShakeMap for that.
When
Magnitude
M 2.5 (ml)
Depth
28 km below the surface
Felt
no reports yet
Status
Automatic — a machine’s first estimate, which may change

USGS · last changed by USGS · we first saw it 59 minutes ago

A magnitude 2.5 earthquake was recorded 60 km SSE of Perryville, Alaska at 15:03 UTC on 2026-10-04. 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 170 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 89,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 63,000× the energy of this one
  3. Around the size people start to feel M 3.0 5.6× the energy of this one
  4. This earthquake M 2.5 about 170 lb of TNT

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 7.8 on 2020-07-22 — about 89,000,000 times the energy of this one.

Before 2016, the USGS record lists 6 earthquakes of M5 or more within 50 km; the five largest:

  1. 8.2 1938 Semidi Islands, Alaska Earthquake · 45 km SE of this epicentre
  2. 6.6 104 km SSE of Perryville, Alaska · 45 km S of this epicentre
  3. 6.2 64 km SSE of Perryville, Alaska · 4 km SSE of this epicentre
  4. 6.2 74 km SE of Perryville, Alaska · 22 km ESE of this epicentre
  5. 5.8 43 km SSE of Perryville, Alaska · 18 km NW 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 55.4180, -158.7590. 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.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.