QuakeIndex

Earthquake · reviewed by a seismologist

M 7.2mww

2023 Sand Point, Alaska Earthquake

· 25 km deep · released about 950 kilotons of TNT

10 km30 km60 km120 km N
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 7.2 (mww)
Depth
25 km below the surface
Felt
165 reports · strongest reported intensity VII
Measured shaking
intensity VII (ShakeMap)
USGS impact alert
green
Tsunami
USGS flagged this event for tsunami evaluation. Follow tsunami.gov for official messages.
Nearest
Aleutians East Borough, 123 km NW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 438 days ago

This was a major earthquake. Serious damage is likely near the epicentre. Follow official information from USGS and local authorities. 165 people have reported feeling it to USGS.

How big was it?

This earthquake released about 950 kilotons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 8.2 would have released about 32 times as much.

  1. Great Alaska earthquake 1964 M 9.2 1,000× the energy of this one
  2. Tōhoku, Japan 2011 M 9.1 710× the energy of this one
  3. San Francisco 1906 M 7.9 11× the energy of this one
  4. This earthquake M 7.2 about 950 kilotons of TNT
  5. Ridgecrest, California 2019 M 7.1 this one released 1.4× more
  6. Loma Prieta, California 1989 M 6.9 this one released 2.8× 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 54.3926, -160.7620. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Aleutians East Borough, AK 123 km (77 mi) SE of here earthquakes near Aleutians East Borough

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

Aftershocks so far

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

  1. 2.9 86 km SSW of Sand Point, Alaska
  2. 3.1 85 km SSW of Sand Point, Alaska
  3. 4.0 Alaska Peninsula
  4. 2.3 123 km S of Sand Point, Alaska
  5. 2.3 110 km S of Sand Point, Alaska
  6. 3.2 82 km SSW of Sand Point, Alaska
  7. 3.0 114 km S of Sand Point, Alaska
  8. 4.2 Alaska Peninsula
  9. 4.0 118 km S of Sand Point, Alaska
  10. 3.4 120 km S of Sand Point, Alaska
  11. 3.1 80 km ESE of King Cove, Alaska
  12. 4.7 91 km SSW of Sand Point, Alaska
  13. 3.4 119 km S of Sand Point, Alaska
  14. 2.2 96 km SSW of Sand Point, Alaska
  15. 2.2 73 km SSW of Sand 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 5.8 on 2018-07-19.

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

On USGS

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