QuakeIndex

Earthquake · reviewed by a seismologist

M 2.0ml

21 km SSE of Karluk, Alaska

Yes. A magnitude 2.0 earthquake was recorded 21 km SSE of Karluk, Alaska at 07:47 UTC on 2024-07-28, 12 km deep.

· 12 km deep · released about 30 lb of TNT

10 km30 km60 km120 km N Kodiak Island Borough 41 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 2.0 (ml)
Depth
12 km below the surface
Felt
no reports yet
Nearest
Kodiak Island Borough, 41 km NNE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 798 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth, people at rest would likely notice it out to about 11 km (7 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 30 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.0 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 500,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 350,000× the energy of this one
  3. Around the size people start to feel M 3.0 32× the energy of this one
  4. This earthquake M 2.0 about 30 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 4.9 on 2019-06-30 — about 22,000 times the energy of this one.

Before 2016, the USGS record lists 22 earthquakes of M5 or more within 50 km; the five largest:

  1. 7.1 4 km ENE of Karluk, Alaska · 22 km NNW of this epicentre
  2. 7.0 26 km SSE of Karluk, Alaska · 7 km SSW of this epicentre
  3. 6.5 24 km SSW of Larsen Bay, Alaska · 8 km SE of this epicentre
  4. 6.4 29 km N of Akhiok, Alaska · 22 km S of this epicentre
  5. 6.0 28 km N of Akhiok, Alaska · 22 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 57.3997, -154.2941. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Kodiak Island Borough, AK 41 km (25 mi) NNE earthquakes near Kodiak Island Borough

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

Aftershocks so far

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

  1. 1.8 19 km NNE of Karluk, Alaska
  2. 2.1 21 km S of Larsen Bay, Alaska
  3. 1.7 26 km NNW of Karluk, Alaska
  4. 1.8 27 km N of Karluk, Alaska
  5. 2.6 13 km NNE of Karluk, Alaska
  6. 1.7 3 km NE of Karluk, Alaska
  7. 1.8 24 km WSW of Karluk, Alaska
  8. 1.7 22 km NE of Karluk, Alaska
  9. 2.2 18 km N of Karluk, Alaska
  10. 2.7 31 km S of Larsen Bay, Alaska
  11. 2.0 31 km W of Old Harbor, Alaska
  12. 1.8 16 km NW of Karluk, Alaska
  13. 1.8 25 km SW of Larsen Bay, Alaska
  14. 1.8 35 km SW of Karluk, Alaska
  15. 1.6 14 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.