QuakeIndex

Earthquake · automatic estimate, may change

M 1.6ml

119 km E of McCarthy, Alaska

Yes. A magnitude 1.6 earthquake was recorded 119 km E of McCarthy, Alaska at 05:20 UTC on 2021-10-06, less than 1 km deep. The magnitude and location are an automatic first estimate and may change.

· 0.0 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
0.0 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 1865 days ago

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

At this magnitude and depth, people at rest would likely notice it out to about 11 km (7 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 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.

For this area

The largest earthquake within 50 km since 2016 was M 4.9 on 2021-05-09 — about 89,000 times the energy of this one.

Before 2016, the USGS record lists 10 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.1 109 km E of McCarthy, Alaska · 32 km SSW of this epicentre
  2. 5.7 152 km E of McCarthy, Alaska · 39 km ESE of this epicentre
  3. 5.5 87 km ENE of McCarthy, Alaska · 35 km WNW of this epicentre
  4. 5.4 140 km SSE of Alcan Border, Alaska · 23 km ESE of this epicentre
  5. 5.4 136 km SSE of Alcan Border, Alaska · 32 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 61.5313, -140.6943. Map © OpenStreetMap contributors.

Aftershocks so far

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

  1. 1.5 136 km E of McCarthy, Alaska
  2. 1.6 121 km E of McCarthy, Alaska
  3. 2.0 97 km E of McCarthy, Alaska
  4. 1.6 100 km E of McCarthy, Alaska
  5. 3.0 100 km E of McCarthy, Alaska
  6. 1.5 119 km E of McCarthy, Alaska
  7. 1.6 143 km E of McCarthy, Alaska
  8. 2.8 126 km E of McCarthy, Alaska
  9. 1.9 99 km E of McCarthy, Alaska
  10. 1.7 103 km E of McCarthy, Alaska
  11. 1.5 128 km SSE of Alcan Border, Alaska
  12. 1.5 136 km E of McCarthy, Alaska
  13. 1.9 103 km E of McCarthy, Alaska
  14. 1.6 Southern Alaska
  15. 1.7 121 km E 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.