QuakeIndex

Earthquake · reviewed by a seismologist

M 3.2ml

Unimak Island region, Alaska

· 35 km deep · released about 1,900 lb 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 3.2 (ml)
Depth
35 km below the surface
Felt
no reports yet
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1324 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 1,900 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.2 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 180,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 7,900× the energy of this one
  3. Magna, Utah 2020 M 5.7 5,600× the energy of this one
  4. This earthquake M 3.2 about 1,900 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 2× 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 53.8338, -163.3080. Map © OpenStreetMap contributors.

Aftershocks so far

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

  1. 2.7 152 km S of False Pass, Alaska
  2. 2.9 146 km S of False Pass, Alaska
  3. 2.2 Unimak Island region, Alaska
  4. 2.5 111 km SSW of False Pass, Alaska
  5. 2.6 152 km S of False Pass, Alaska
  6. 2.6 155 km S of False Pass, Alaska
  7. 2.9 149 km S of False Pass, Alaska
  8. 2.9 96 km S of False Pass, Alaska
  9. 2.5 68 km S of False Pass, Alaska
  10. 3.7 Unimak Island region, Alaska
  11. 4.6 Unimak Island region, Alaska
  12. 2.7 158 km S of False Pass, Alaska
  13. 2.7 157 km S of False Pass, Alaska
  14. 3.2 156 km S of False Pass, Alaska
  15. 2.6 151 km S of False Pass, 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 5.9 on 2016-10-27 — it released about 11,000 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.