QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1ml

Earthquake near Seward, AK

No earthquake was likely felt in Seward in the 24 hours to 2:30 pm AKST (23:30 UTC). The last one was M 4.3, 83 km (52 mi) W, at 2:30 am AKST on 1 November 2026, estimated intensity II (weak) in town; 115 felt reports to USGS. Every earthquake near Seward

This page: a magnitude 2.1 earthquake was recorded 8 km (5 mi) west-southwest of Seward, AK, at 2:31 pm AKDT on 25 October 2023 (22:31 UTC), 3.9 km deep.

USGS: 7 km W of Lowell Point, Alaska

2:31 pm AKDT, Oct 25, 2023 · · 3.9 km deep · released about 43 lb of TNT

Every earthquake near Seward 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
2:31 pm AKDT on 25 October 2023 ()
Where
8 km (5 mi) west-southwest of Seward, AK · earthquakes near Seward
Magnitude
M 2.1 (ml)
Depth
3.9 km below the surface
Felt
no reports yet
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1098 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 17 km (11 mi) from the epicentre. In Seward, 8 km away, the estimate is intensity II (weak). 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.

Likely felt in: Seward 8 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 43 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 350,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 250,000× the energy of this one
  3. Around the size people start to feel M 3.0 22× the energy of this one
  4. This earthquake M 2.1 about 43 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

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

Before 2016, the USGS record lists 6 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.6 3 km SW of Bear Creek, Alaska · 11 km NE of this epicentre
  2. 6.3 37 km SSE of Lowell Point, Alaska · 40 km SSE of this epicentre
  3. 5.9 33 km SSE of Lowell Point, Alaska · 37 km SE of this epicentre
  4. 5.8 33 km ESE of Bear Creek, Alaska · 43 km E of this epicentre
  5. 5.4 12 km ESE of Lowell Point, Alaska · 19 km ESE 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 60.0705, -149.5695. Map © OpenStreetMap contributors.

Aftershocks so far

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

  1. 2.4 20 km S of Cooper Landing, Alaska
  2. 2.0 24 km WSW of Lowell Point, Alaska
  3. 1.6 24 km WNW of Bear Creek, Alaska
  4. 1.5 5 km ENE of Cooper Landing, Alaska
  5. 1.6 35 km S of Lowell Point, Alaska
  6. 1.8 17 km WSW of Cooper Landing, Alaska
  7. 1.9 22 km SW of Lowell Point, Alaska
  8. 1.7 6 km WNW of Seward, Alaska
  9. 1.5 6 km NW of Bear Creek, Alaska
  10. 1.7 15 km SE of Lowell Point, Alaska
  11. 1.5 8 km SE of Lowell Point, Alaska
  12. 1.6 23 km SSW of Cooper Landing, Alaska
  13. 1.7 18 km SW of Lowell Point, Alaska
  14. 1.7 44 km SSW of Lowell Point, Alaska
  15. 1.5 11 km WSW of Moose Pass, 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.