Earthquake near Susitna North, AK

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 36 km (22 mi) from the epicentre. In Susitna North, 22 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: Susitna North 22 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 950 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.0 would have released about 32 times as much.

1. Northridge, California 1994 M 6.7 350,000× the energy of this one
2. Mineral, Virginia 2011 M 5.8 16,000× the energy of this one
3. Magna, Utah 2020 M 5.7 11,000× the energy of this one
4. This earthquake M 3.0 about 950 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 2023-01-16 — about 180 times the energy of this one.

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

1. 5.9 23 km NE of Willow, Alaska · 25 km SW of this epicentre Jan 1, 1975
2. 5.8 37 km ENE of Susitna North, Alaska · 26 km NNE of this epicentre Jul 3, 1929
3. 5.8 14 km NNE of Fishhook, Alaska · 32 km SE of this epicentre Aug 14, 1984
4. 5.4 25 km NNW of Willow, Alaska · 38 km WSW of this epicentre May 10, 1962
5. 5.1 21 km SSE of Susitna North, Alaska · 17 km SW of this epicentre Dec 30, 1974

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 62.0920, -149.4570. Map © OpenStreetMap contributors.

Nearby places

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

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

1. 2.3 12 km SSE of Susitna North, Alaska 07:30 UTC
2. 3.0 31 km ESE of Susitna North, Alaska 13:08 UTC
3. 1.9 26 km SE of Susitna North, Alaska 21:26 UTC
4. 1.7 12 km N of Meadow Lakes, Alaska 13:47 UTC
5. 1.9 9 km E of Susitna North, Alaska 05:55 UTC
6. 2.1 18 km NNE of Fishhook, Alaska 02:35 UTC
7. 1.8 17 km ENE of Willow, Alaska 20:05 UTC
8. 2.0 18 km E of Chase, Alaska 03:04 UTC
9. 1.8 18 km NNE of Fishhook, Alaska 02:00 UTC
10. 1.8 18 km NNE of Fishhook, Alaska 08:58 UTC
11. 1.9 11 km NNE of Houston, Alaska 17:37 UTC
12. 1.7 17 km NNE of Fishhook, Alaska 15:34 UTC
13. 2.1 45 km ENE of Susitna North, Alaska 19:18 UTC
14. 1.8 9 km S of Susitna North, Alaska 15:30 UTC
15. 2.1 15 km ENE of Susitna North, Alaska 08:06 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 12:37 UTC. QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.

On USGS

• The official USGS event page — the source of record for every value above
• Did you feel it? Report it to USGS — reports go to USGS, not to us
• ShakeMap for this event, when USGS has produced one

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