QuakeIndex

Earthquake · reviewed by a seismologist

M 2.9ml

100 km E of McCarthy, Alaska

Yes. A magnitude 2.9 earthquake was recorded 100 km E of McCarthy, Alaska at 02:11 UTC on 2024-07-11, 1.2 km deep.

· 1.2 km deep · released about 680 lb of TNT

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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 2.9 (ml)
Depth
1.2 km below the surface
Felt
no reports yet
Nearest mapped fault
Totschunda fault, 14 km from its surface trace — near is not the same as on
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 784 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

At this magnitude and depth, people at rest would likely notice it out to about 32 km (20 mi) from the epicentre. 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 680 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 22,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 16,000× the energy of this one
  3. Around the size people start to feel M 3.0 1.4× the energy of this one
  4. This earthquake M 2.9 about 680 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 4.9 on 2021-05-09 — about 1,000 times the energy of this one.

Before 2016, the USGS record lists 5 earthquakes of M5 or more within 50 km:

  1. 6.1 109 km E of McCarthy, Alaska · 34 km SSE of this epicentre
  2. 5.5 87 km ENE of McCarthy, Alaska · 15 km WNW of this epicentre
  3. 5.4 140 km SSE of Alcan Border, Alaska · 43 km ESE of this epicentre
  4. 5.3 136 km E of McCarthy, Alaska · 39 km ESE of this epicentre
  5. 5.2 130 km SSE of Alcan Border, Alaska · 47 km E 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 61.5612, -141.0587. Map © OpenStreetMap contributors.

Aftershocks so far

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

  1. 1.5 94 km E of McCarthy, Alaska
  2. 1.5 96 km E of McCarthy, Alaska
  3. 1.9 93 km E of McCarthy, Alaska
  4. 3.5 104 km E of McCarthy, Alaska
  5. 1.9 81 km E of McCarthy, Alaska
  6. 2.0 86 km E of McCarthy, Alaska
  7. 2.6 82 km E of McCarthy, Alaska
  8. 3.2 123 km E of McCarthy, Alaska
  9. 1.6 103 km ESE of McCarthy, Alaska
  10. 3.5 91 km E of McCarthy, Alaska
  11. 1.5 106 km ESE of McCarthy, Alaska
  12. 2.5 106 km E of McCarthy, Alaska
  13. 1.8 71 km E of McCarthy, Alaska
  14. 1.5 91 km E of McCarthy, Alaska
  15. 2.2 129 km ESE of McCarthy, 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.