Earthquake.now

M3.1 Earthquake near Nelson Lagoon, United States — 04 September 2026

A minor earthquake of magnitude 3.1 was recorded near Nelson Lagoon, United States on , with an epicentre 48 km northwest of Nelson Lagoon, at a focal depth of 216.7 km. It ranked as the 307th strongest of 7941 earthquakes recorded in the United States in the preceding 30 days.

3.1 Minor

Time (UTC): 2026-09-04 01:27:46

Time (your timezone): —

Magnitude: 3.1 (minor)

Focal depth: 216.7 km (intermediate)

Epicentre: 56.2730, -161.8250

Location: 48 km NW of Nelson Lagoon, Alaska

Country: United States

USGS link to NOAA tsunami information: Not linked

Review status: Reviewed

Source: USGS event page

How strong was this earthquake?

Minor earthquakes in this range are felt by people close to the epicentre as a brief jolt or rattle, but they very rarely cause any damage.

A magnitude 3.1 earthquake radiates roughly 674 kg of TNT equivalent in seismic energy.

The USGS assigns this earthquake a significance score of 148, which is below the USGS threshold of more than 600 for its significant-earthquake list. The ranking combines magnitude with available Did You Feel It responses and PAGER alert level; it is not a direct measurement of damage.

What the magnitude scale actually measures →

When it happened locally

That is about 14:40 local solar time at the epicentre, during the afternoon.

This event was deeper than 100% of the 153,430 earthquakes recorded in the United States in our catalogue and stronger than 97% of them.

Where was the epicentre?

The epicentre was located at 56.2730, -161.8250 — 48 km northwest of Nelson Lagoon. The closest other recorded event was a magnitude 3.7 earthquake 26 km north-northeast of here on 03 September 2026.

The nearest other settlements in our records are Cold Bay (152 km south-southwest), Chignik Lake (162 km northeast), Akutan (220 km south-southwest) and False Pass (232 km south-southwest).

Why the 217 km depth matters

At 217 km this was an intermediate-depth earthquake. Energy from events at this depth spreads out before it reaches the surface, which usually means weaker shaking near the epicentre than a shallow quake of the same magnitude, but shaking felt across a wider area.

This catalogue does not ingest eyewitness responses, so it cannot confirm where this earthquake was felt. Based on magnitude alone, an event this size may be noticed locally, especially close to the epicentre. Its intermediate depth normally reduces peak shaking near the epicentre compared with a shallow event of the same magnitude.

Read more on how focal depth changes what you feel →

What does the tsunami information flag mean?

The USGS record does not carry a link to NOAA tsunami information. That field is not an all-clear and does not state whether a tsunami occurred. In this case, a damaging tsunami would be less likely because at M3.1 it falls below the magnitude 6.5 threshold that generally applies before a submarine earthquake displaces enough water to generate a damaging tsunami; its 217 km focal depth is too great to deform the sea floor significantly; it occurred inland rather than beneath the sea floor. For an active coastal alert, use tsunami.gov or your local warning authority.

How earthquakes generate tsunamis, and what the alert levels mean →

Aftershocks and local seismic history

No further earthquakes have been recorded within about 150 km of the epicentre in the 5 hours since this event.

58 earthquakes of magnitude 4 or above have been logged within roughly 200 km of this epicentre in our catalogue. The strongest was a magnitude 7.3 event near Sand Point on 16 July 2025. This M3.1 event released about 2.0 million times less energy than that event.

71 earthquakes have been recorded within 100 km of this epicentre in the past year, 3 of them in the past 30 days.

How long aftershock sequences last, and how large they get →

Where this event sits in the record

This earthquake is part of the September 2026 worldwide record, and of earthquakes in the United States during September 2026. Browse the full monthly archive to compare periods.

Nearest recorded earthquakes to this epicentre

Other recent earthquakes in the United States

All recorded earthquakes in the United States →

Other magnitude 3 earthquakes worldwide

All magnitude 3 earthquakes →

Questions about this earthquake

How strong was the earthquake near Nelson Lagoon?

It measured magnitude 3.1 — a minor earthquake. A magnitude 3.1 earthquake radiates roughly 674 kg of TNT equivalent in seismic energy.

How deep was the earthquake near Nelson Lagoon?

The focus was 217 km below the surface, which counts as intermediate.

Was the Nelson Lagoon earthquake felt at the surface?

At magnitude 3.1 and a focal depth of 217 km, the depth spreads the energy out, so shaking is weaker overhead but reaches further.

When did the earthquake near Nelson Lagoon happen?

04 September 2026 at 01:27 UTC.

Was there a tsunami?

No. The USGS record carries no tsunami-information link for this event.

Have there been aftershocks?

No further earthquakes have been recorded within about 150 km of the epicentre in the 5 hours since this event.

How often do earthquakes happen near Nelson Lagoon?

58 earthquakes of magnitude 4 or above have been logged within roughly 200 km of this epicentre in our catalogue. The strongest was a magnitude 7.3 event near Sand Point on 16 July 2025. This M3.1 event released about 2.0 million times less energy than that event.