QuakeIndex

Earthquake · reviewed by a seismologist

M 2.6ml

128 km SSE of Ugashik, Alaska

Yes. A magnitude 2.6 earthquake was recorded 128 km SSE of Ugashik, Alaska at 00:18 UTC on 2019-02-01, 52 km deep.

· 52 km deep · released about 240 lb of TNT

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 2.6 (ml)
Depth
52 km below the surface
Felt
no reports yet
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2002 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 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 240 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 63,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 45,000× the energy of this one
  3. Around the size people start to feel M 3.0 4× the energy of this one
  4. This earthquake M 2.6 about 240 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 4.5 on 2017-03-28 — about 710 times the energy of this one.

Before 2016, the USGS record lists 14 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.8 117 km SSE of Ugashik, Alaska · 13 km WNW of this epicentre
  2. 6.4 104 km SSE of Ugashik, Alaska · 32 km WNW of this epicentre
  3. 6.3 112 km E of Chignik, Alaska · 47 km SSW of this epicentre
  4. 6.1 132 km E of Chignik, Alaska · 40 km S of this epicentre
  5. 5.4 115 km SSE of Ugashik, Alaska · 13 km NW 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 56.5523, -156.2235. Map © OpenStreetMap contributors.

Aftershocks so far

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

  1. 2.2 110 km WSW of Akhiok, Alaska
  2. 2.0 112 km W of Akhiok, Alaska
  3. 2.9 137 km WSW of Akhiok, Alaska
  4. 2.1 114 km ENE of Chignik, Alaska
  5. 2.4 128 km E of Chignik, Alaska
  6. 2.7 97 km SE of Ugashik, Alaska
  7. 2.9 119 km E of Chignik, Alaska
  8. 2.2 125 km E of Chignik, Alaska
  9. 2.2 114 km SE of Ugashik, Alaska
  10. 2.4 109 km E of Chignik, Alaska
  11. 2.6 100 km W of Akhiok, Alaska
  12. 1.9 125 km SSE of Ugashik, Alaska
  13. 1.8 117 km ENE of Chignik, Alaska
  14. 2.2 135 km SW of Akhiok, Alaska
  15. 1.5 93 km SE of Ugashik, 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.