QuakeIndex

Earthquake · reviewed by a seismologist

M 2.5ml

238 km SSE of Chiniak, Alaska

· 12 km deep · released about 170 lb of TNT

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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 2.5 (ml)
Depth
12 km below the surface
Felt
no reports yet
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2043 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 170 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 89,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 63,000× the energy of this one
  3. Around the size people start to feel M 3.0 5.6× the energy of this one
  4. This earthquake M 2.5 about 170 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 55.7172, -150.4751. Map © OpenStreetMap contributors.

Aftershocks so far

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

  1. 3.1 218 km SE of Chiniak, Alaska
  2. 2.8 224 km SE of Chiniak, Alaska
  3. 3.2 241 km SE of Chiniak, Alaska
  4. 3.7 247 km SE of Chiniak, Alaska
  5. 3.6 233 km SE of Chiniak, Alaska
  6. 2.7 229 km SE of Chiniak, Alaska
  7. 3.1 228 km SE of Chiniak, Alaska
  8. 1.7 227 km SE of Chiniak, Alaska
  9. 2.6 234 km SE of Chiniak, Alaska
  10. 3.7 223 km SE of Chiniak, Alaska
  11. 2.6 240 km SE of Chiniak, Alaska
  12. 2.7 226 km SE of Chiniak, Alaska
  13. 2.8 217 km SE of Chiniak, Alaska
  14. 3.3 241 km SSE of Chiniak, Alaska
  15. 2.6 226 km SE of Chiniak, 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 5.0 on 2018-01-26 — it released about 5,600 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.