QuakeIndex

Earthquake · automatic estimate, may change

M 3.1ml

30 km NNE of Karluk, Alaska

Yes. A magnitude 3.1 earthquake was recorded 30 km NNE of Karluk, Alaska at 15:13 UTC on 2025-10-26, 55 km deep. The magnitude and location are an automatic first estimate and may change.

· 55 km deep · released about 1,300 lb of TNT

10 km30 km60 km120 km N Kodiak Island Borough 26 km
Distance rings around the epicentre, with the nearest towns at their true direction and later quakes as coloured dots. Not a shaking map — see the USGS ShakeMap for that.
When
Magnitude
M 3.1 (ml)
Depth
55 km below the surface
Felt
no reports yet
Nearest
Kodiak Island Borough, 26 km ESE
Status
Automatic — a machine’s first estimate, which may change

USGS · last changed by USGS · we first saw it 301 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

At this magnitude and depth it was probably too small to be felt, even directly above it. 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 1,300 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 250,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 11,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 7,900× the energy of this one
  4. This earthquake M 3.1 about 1,300 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.4× 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 5.0 on 2023-06-18 — about 710 times the energy of this one.

Before 2016, the USGS record lists 9 earthquakes of M5 or more within 50 km; the five largest:

  1. 7.1 4 km ENE of Karluk, Alaska · 27 km SSW of this epicentre
  2. 6.0 15 km S of Larsen Bay, Alaska · 50 km SSE of this epicentre
  3. 5.8 29 km NNE of Karluk, Alaska · 5 km ESE of this epicentre
  4. 5.7 6 km NE of Larsen Bay, Alaska · 35 km SE of this epicentre
  5. 5.6 24 km N of Larsen Bay, Alaska · 19 km ESE 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 57.8264, -154.2990. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Kodiak Island Borough, AK 26 km (16 mi) ESE earthquakes near Kodiak Island Borough

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

56 earthquakes have been recorded within 50 km since this one.

  1. 2.7 63 km N of Larsen Bay, Alaska
  2. 1.9 27 km NNW of Karluk, Alaska
  3. 2.2 9 km SW of Karluk, Alaska
  4. 2.0 57 km NNW of Karluk, Alaska
  5. 1.9 14 km WNW of Karluk, Alaska
  6. 1.9 19 km NE of Karluk, Alaska
  7. 1.8 22 km NNE of Karluk, Alaska
  8. 1.6 18 km N of Larsen Bay, Alaska
  9. 1.8 13 km WSW of Larsen Bay, Alaska
  10. 1.6 70 km NNE of Karluk, Alaska
  11. 1.7 33 km N of Karluk, Alaska
  12. 2.0 20 km NW of Karluk, Alaska
  13. 1.7 40 km NW of Karluk, Alaska
  14. 2.2 22 km NNW of Larsen Bay, Alaska
  15. 2.1 16 km NNW of Karluk, 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

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