QuakeIndex

Earthquake · reviewed by a seismologist

M 4.5mww

47 km NW of Ninilchik, Alaska

· 88 km deep · released about 85 tons of TNT

10 km30 km60 km120 km N Kenai Peninsula Borough 5 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 4.5 (mww)
Depth
88 km below the surface
Felt
31 reports · strongest reported intensity IV
Measured shaking
intensity III (ShakeMap)
Tsunami
USGS flagged this event for tsunami evaluation. Follow tsunami.gov for official messages.
Nearest
Kenai Peninsula Borough, 5 km N
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 719 days ago

This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon. 31 people have reported feeling it to USGS.

How big was it?

This earthquake released about 85 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.5 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 2,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 89× the energy of this one
  3. Magna, Utah 2020 M 5.7 63× the energy of this one
  4. This earthquake M 4.5 about 85 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 180× 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 60.3222, -152.3227. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Kenai Peninsula Borough, AK 5 km (3 mi) S of here earthquakes near Kenai Peninsula Borough

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

Aftershocks so far

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

  1. 1.7 57 km WNW of Happy Valley, Alaska
  2. 1.9 65 km WNW of Happy Valley, Alaska
  3. 1.6 37 km W of Salamatof, Alaska
  4. 1.7 46 km WNW of Anchor Point, Alaska
  5. 2.0 45 km WNW of Ninilchik, Alaska
  6. 2.3 47 km W of Salamatof, Alaska
  7. 1.8 19 km WNW of Ninilchik, Alaska
  8. 1.5 48 km WNW of Happy Valley, Alaska
  9. 1.7 56 km WSW of Salamatof, Alaska
  10. 1.7 63 km W of Happy Valley, Alaska
  11. 1.5 26 km W of Happy Valley, Alaska
  12. 1.5 56 km W of Happy Valley, Alaska
  13. 1.8 62 km WNW of Anchor Point, Alaska
  14. 1.7 76 km W of Salamatof, Alaska
  15. 2.4 63 km WNW of Anchor Point, 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 5.1 on 2022-01-21 — it released about 7.9 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.