QuakeIndex

Earthquake · reviewed by a seismologist

M 5.5mw

26 km SSE of King Salmon, Alaska

· 204 km deep · released about 2.7 kilotons of TNT

10 km30 km60 km120 km N Lake and Peninsula Borough 41 kmBristol Bay Borough 42 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 5.5 (mw)
Depth
204 km below the surface
Felt
10 reports · strongest reported intensity III
Measured shaking
intensity IV (ShakeMap)
USGS impact alert
green
Tsunami
USGS flagged this event for tsunami evaluation. Follow tsunami.gov for official messages.
Nearest
Lake and Peninsula Borough, 41 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1152 days ago

This was a moderate earthquake. Shaking at this size can damage poorly built structures close to the epicentre. 10 people have reported feeling it to USGS.

How big was it?

This earthquake released about 2.7 kilotons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 6.5 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 63× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 2.8× the energy of this one
  3. Magna, Utah 2020 M 5.7 2× the energy of this one
  4. This earthquake M 5.5 about 2.7 kilotons of TNT
  5. Around the size people start to feel M 3.0 this one released 5,600× 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 58.4734, -156.4569. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Lake and Peninsula Borough, AK 41 km (25 mi) N of here earthquakes near Lake and Peninsula Borough
Bristol Bay Borough, AK 42 km (26 mi) SE of here earthquakes near Bristol Bay Borough
Dillingham Census Area, AK 158 km (98 mi) SE of here earthquakes near Dillingham Census Area

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. 1.9 61 km SE of King Salmon, Alaska
  2. 2.2 65 km SSE of King Salmon, Alaska
  3. 2.9 22 km SE of King Salmon, Alaska
  4. 2.0 54 km SE of King Salmon, Alaska
  5. 2.3 68 km SE of King Salmon, Alaska
  6. 2.5 67 km SE of King Salmon, Alaska
  7. 2.7 60 km SE of King Salmon, Alaska
  8. 2.0 50 km SSE of King Salmon, Alaska
  9. 2.3 27 km SSE of King Salmon, Alaska
  10. 1.9 52 km SE of King Salmon, Alaska
  11. 1.7 54 km SE of King Salmon, Alaska
  12. 1.9 54 km SE of King Salmon, Alaska
  13. 2.0 59 km SSE of King Salmon, Alaska
  14. 2.0 56 km SE of King Salmon, Alaska
  15. 2.3 40 km ENE of Egegik, 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 4.1 on 2016-05-31.

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

On USGS

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