QuakeIndex

Earthquake · reviewed by a seismologist

M 2.8ml

3 km NNW of Susitna North, Alaska

· 45 km deep · released about 480 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Matanuska-Susitna Borough 21 kmAnchorage Municipality 117 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 2.8 (ml)
Depth
45 km below the surface
Felt
no reports yet
Nearest
Matanuska-Susitna Borough, 21 km ENE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1387 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 480 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 32,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 22,000× the energy of this one
  3. Around the size people start to feel M 3.0 2× the energy of this one
  4. This earthquake M 2.8 about 480 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.

Where

Epicentre 62.1891, -149.8650. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Matanuska-Susitna Borough, AK 21 km (13 mi) WSW of here earthquakes near Matanuska-Susitna Borough
Anchorage Municipality, AK 117 km (73 mi) NNW of here earthquakes near Anchorage Municipality

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

Aftershocks so far

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

  1. 1.6 Southern Alaska
  2. 1.8 23 km N of Willow, Alaska
  3. 1.9 17 km SSE of Susitna North, Alaska
  4. 1.9 13 km NNE of Houston, Alaska
  5. 1.9 Southern Alaska
  6. 2.1 16 km SSW of Trapper Creek, Alaska
  7. 1.7 25 km SE of Susitna North, Alaska
  8. 2.3 24 km ENE of Susitna North, Alaska
  9. 2.2 11 km NNW of Susitna North, Alaska
  10. 1.8 7 km NNW of Susitna North, Alaska
  11. 1.6 17 km NE of Chase, Alaska
  12. 1.5 17 km SSW of Trapper Creek, Alaska
  13. 1.6 9 km NW of Susitna North, Alaska
  14. 1.6 12 km ENE of Willow, Alaska
  15. 2.3 22 km E of Susitna North, 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 4.6 on 2020-11-26 — it released about 500 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.