QuakeIndex

Earthquake · reviewed by a seismologist

M 3.2ml

54 km SSE of Old Harbor, Alaska

Yes. A magnitude 3.2 earthquake was recorded 54 km SSE of Old Harbor, Alaska, at 3:22 pm AKDT on 1 April 2024 (23:22 UTC), 43 km deep.

· 43 km deep · released about 1,900 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Kodiak Island Borough 120 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 3.2 (ml)
Depth
43 km below the surface
Felt
no reports yet
Nearest
Kodiak Island Borough, 120 km NNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 884 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, people at rest would likely notice it out to about 20 km (12 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 1,900 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.2 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 180,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 7,900× the energy of this one
  3. Magna, Utah 2020 M 5.7 5,600× the energy of this one
  4. This earthquake M 3.2 about 1,900 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 2× 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 5.4 on 2017-05-11 — about 2,000 times the energy of this one.

Before 2016, the USGS record lists 53 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.9 47 km S of Old Harbor, Alaska · 15 km WNW of this epicentre
  2. 6.8 100 km SSE of Old Harbor, Alaska · 46 km S of this epicentre
  3. 6.6 88 km SSE of Old Harbor, Alaska · 34 km SSE of this epicentre
  4. 6.6 94 km SSE of Old Harbor, Alaska · 41 km SSE of this epicentre
  5. 6.5 85 km SSE of Old Harbor, Alaska · 31 km S 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 56.7339, -153.0513. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Kodiak Island Borough, AK 120 km (74 mi) NNW earthquakes near Kodiak Island Borough

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

Aftershocks so far

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

  1. 1.9 30 km SE of Old Harbor, Alaska
  2. 1.8 11 km SE of Old Harbor, Alaska
  3. 2.3 61 km SE of Akhiok, Alaska
  4. 2.5 35 km SSE of Old Harbor, Alaska
  5. 2.0 35 km SE of Old Harbor, Alaska
  6. 2.1 26 km S of Old Harbor, Alaska
  7. 3.4 51 km SSE of Old Harbor, Alaska
  8. 2.2 26 km S of Old Harbor, Alaska
  9. 3.3 95 km SSE of Old Harbor, Alaska
  10. 2.6 42 km SE of Old Harbor, Alaska
  11. 2.6 67 km S of Old Harbor, Alaska
  12. 2.5 46 km S of Old Harbor, Alaska
  13. 2.9 85 km S of Old Harbor, Alaska
  14. 2.0 44 km S of Old Harbor, Alaska
  15. 2.9 102 km SSE of Old Harbor, 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.