QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1ml

161 km SW of Nikolski, Alaska

· 35 km deep · released about 43 lb of TNT

Felt it? Tell USGS Check my area
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 2.1 (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 577 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

How big was it?

This earthquake released about 43 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 350,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 250,000× the energy of this one
  3. Around the size people start to feel M 3.0 22× the energy of this one
  4. This earthquake M 2.1 about 43 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 52.0144, -170.6871. Map © OpenStreetMap contributors.

Aftershocks so far

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

  1. 2.6 126 km SW of Nikolski, Alaska
  2. 2.8 182 km SW of Nikolski, Alaska
  3. 3.2 139 km WSW of Nikolski, Alaska
  4. 2.9 184 km SW of Nikolski, Alaska
  5. 3.6 132 km SW of Nikolski, Alaska
  6. 4.0 133 km SW of Nikolski, Alaska
  7. 2.7 177 km SW of Nikolski, Alaska
  8. 2.8 144 km SW of Nikolski, Alaska
  9. 2.5 133 km SW of Nikolski, Alaska
  10. 2.8 130 km SW of Nikolski, Alaska
  11. 3.8 130 km SW of Nikolski, Alaska
  12. 3.2 192 km SW of Nikolski, Alaska
  13. 3.3 175 km WSW of Nikolski, Alaska
  14. 3.1 139 km WSW of Nikolski, Alaska
  15. 2.7 168 km SW of Nikolski, 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 6.0 on 2024-05-19 — it released about 710,000 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.