QuakeIndex

Earthquake · reviewed by a seismologist

M 2.4ml

118 km SSW of False Pass, Alaska

Yes. A magnitude 2.4 earthquake was recorded 118 km SSW of False Pass, Alaska at 07:48 UTC on 2017-06-25, 25 km deep.

· 25 km deep · released about 120 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 2.4 (ml)
Depth
25 km below the surface
Felt
no reports yet
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2740 days ago

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

At this magnitude and depth it was probably too small to be felt, even directly above it. Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.

How big was it?

This earthquake released about 120 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.4 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 130,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 89,000× the energy of this one
  3. Around the size people start to feel M 3.0 7.9× the energy of this one
  4. This earthquake M 2.4 about 120 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.

For this area

The largest earthquake within 50 km since 2016 was M 5.0 on 2016-06-18 — about 7,900 times the energy of this one.

Before 2016, the USGS record lists 62 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.6 146 km ESE of Akutan, Alaska · 34 km SSE of this epicentre
  2. 6.5 81 km ESE of Akutan, Alaska · 48 km W of this epicentre
  3. 6.4 85 km ESE of Akutan, Alaska · 47 km W of this epicentre
  4. 6.2 Unimak Island region, Alaska · 6 km S of this epicentre
  5. 6.2 102 km SSW of False Pass, Alaska · 19 km N of this epicentre

Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.

Where

Epicentre 53.8325, -163.9440. Map © OpenStreetMap contributors.

Aftershocks so far

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

  1. 3.4 94 km S of False Pass, Alaska
  2. 2.1 109 km SSW of False Pass, Alaska
  3. 2.2 95 km S of False Pass, Alaska
  4. 2.2 102 km S of False Pass, Alaska
  5. 2.2 91 km S of False Pass, Alaska
  6. 2.1 114 km SSW of False Pass, Alaska
  7. 2.6 141 km ESE of Akutan, Alaska
  8. 2.3 97 km SSW of False Pass, Alaska
  9. 2.5 88 km SSW of False Pass, Alaska
  10. 2.3 159 km ESE of Akutan, Alaska
  11. 2.3 84 km S of False Pass, Alaska
  12. 2.1 108 km ESE of Akutan, Alaska
  13. 2.3 106 km SSW of False Pass, Alaska
  14. 2.0 110 km SSW of False Pass, Alaska
  15. 3.2 103 km ESE of Akutan, 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.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.