QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6ml

171 km W of Adak, Alaska

· 11 km deep · released about 7.6 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 1.6 (ml)
Depth
11 km below the surface
Felt
no reports yet
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 949 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 7.6 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,000,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,400,000× the energy of this one
  3. Around the size people start to feel M 3.0 130× the energy of this one
  4. This earthquake M 1.6 about 7.6 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 51.7171, -179.1023. Map © OpenStreetMap contributors.

Aftershocks so far

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

  1. 1.9 165 km W of Adak, Alaska
  2. 2.4 180 km W of Adak, Alaska
  3. 2.0 197 km WSW of Adak, Alaska
  4. 2.3 204 km W of Adak, Alaska
  5. 2.3 142 km W of Adak, Alaska
  6. 2.3 176 km WSW of Adak, Alaska
  7. 2.2 169 km WSW of Adak, Alaska
  8. 2.7 192 km WSW of Adak, Alaska
  9. 2.0 181 km WSW of Adak, Alaska
  10. 1.7 141 km WSW of Adak, Alaska
  11. 2.1 209 km WSW of Adak, Alaska
  12. 2.1 177 km W of Adak, Alaska
  13. 2.2 199 km WSW of Adak, Alaska
  14. 1.9 186 km WSW of Adak, Alaska
  15. 2.0 204 km WSW of Adak, 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 6.2 on 2017-05-08 — it released about 7,900,000 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.