QuakeIndex

Earthquake · reviewed by a seismologist

M 3.7ml

60 km ENE of Ugashik, Alaska

· 122 km deep · released about 5.4 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Lake and Peninsula Borough 42 kmBristol Bay Borough 115 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 3.7 (ml)
Depth
122 km below the surface
Felt
no reports yet
Nearest
Lake and Peninsula Borough, 42 km N
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1137 days ago

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 5.4 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.7 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 32,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 1,400× the energy of this one
  3. Magna, Utah 2020 M 5.7 1,000× the energy of this one
  4. This earthquake M 3.7 about 5.4 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 11× 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.

Where

Epicentre 57.7363, -156.4775. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Lake and Peninsula Borough, AK 42 km (26 mi) S of here earthquakes near Lake and Peninsula Borough
Bristol Bay Borough, AK 115 km (71 mi) SSE of here earthquakes near Bristol Bay Borough

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

Aftershocks so far

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

  1. 1.7 59 km E of Ugashik, Alaska
  2. 2.9 68 km ESE of Egegik, Alaska
  3. 1.8 55 km ENE of Ugashik, Alaska
  4. 2.0 Alaska Peninsula
  5. 2.0 78 km ESE of Egegik, Alaska
  6. 1.5 85 km ENE of Ugashik, Alaska
  7. 2.0 74 km ENE of Ugashik, Alaska
  8. 2.0 81 km ESE of Egegik, Alaska
  9. 2.1 70 km E of Ugashik, Alaska
  10. 2.9 76 km ESE of Egegik, Alaska
  11. 1.6 67 km E of Ugashik, Alaska
  12. 2.1 79 km ESE of Egegik, Alaska
  13. 1.8 80 km ESE of Egegik, Alaska
  14. 2.3 74 km ENE of Ugashik, Alaska
  15. 1.5 52 km ESE of Ugashik, 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.

For this area

The largest earthquake within 50 km in our catalogue was M 4.2 on 2017-10-12 — it released about 5.6 times the energy of this one.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

On USGS

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