QuakeIndex

Earthquake · automatic estimate, may change

M 2.6ml

190 km SE of Chignik, Alaska

· 47 km deep · released about 240 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 2.6 (ml)
Depth
47 km below the surface
Felt
no reports yet
Status
Automatic — a machine’s first estimate, which may change

USGS · last changed by USGS · we first saw it 1794 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 240 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 63,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 45,000× the energy of this one
  3. Around the size people start to feel M 3.0 4× the energy of this one
  4. This earthquake M 2.6 about 240 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 54.9992, -156.4255. Map © OpenStreetMap contributors.

Aftershocks so far

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

  1. 2.9 156 km SE of Chignik, Alaska
  2. 2.9 201 km SE of Perryville, Alaska
  3. 3.2 210 km SE of Chignik, Alaska
  4. 4.3 162 km SE of Chignik, Alaska
  5. 3.8 165 km SE of Chignik, Alaska
  6. 3.2 160 km SE of Chignik, Alaska
  7. 3.6 160 km SE of Chignik, Alaska
  8. 3.0 195 km SE of Perryville, Alaska
  9. 3.3 197 km SE of Perryville, Alaska
  10. 3.3 193 km SE of Perryville, Alaska
  11. 2.5 151 km SE of Chignik, Alaska
  12. 3.2 204 km SE of Perryville, Alaska
  13. 2.5 156 km SE of Chignik, Alaska
  14. 3.0 203 km SE of Chignik, Alaska
  15. 2.5 174 km SE of Chignik, 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 5.4 on 2021-07-29 — it released about 16,000 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.