43 km E of Port Heiden, Alaska

Yes. A magnitude 2.8 earthquake was recorded 43 km E of Port Heiden, Alaska at 15:33 UTC on 2020-01-22, 100 km deep. The magnitude and location are an automatic first estimate and may change.

2020-01-22 15:33 UTC · 100 km deep · released about 480 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: 2020-01-22 15:33 UTC
Magnitude: M 2.8 (ml)
Depth: 100 km below the surface
Felt: no reports yet
Status: Automatic — a machine’s first estimate, which may change

USGS · last changed by USGS 2406 days ago · we first saw it 2406 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 480 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.8 would have released about 32 times as much.

Mineral, Virginia 2011 M 5.8 32,000× the energy of this one
Magna, Utah 2020 M 5.7 22,000× the energy of this one
Around the size people start to feel M 3.0 2× the energy of this one
This earthquake M 2.8 about 480 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 6.2 on 2016-04-02 — about 130,000 times the energy of this one.

Before 2016, the USGS record lists one earthquake of M5 or more within 50 km:

5.1 68 km S of Ugashik, Alaska · 41 km ESE of this epicentre Jun 5, 1984

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

Map loads when it scrolls into view

Aftershocks so far

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

2.3 33 km SE of Port Heiden, Alaska 03:40 UTC
2.1 57 km NE of Chignik, Alaska 00:21 UTC
2.9 53 km E of Port Heiden, Alaska 13:40 UTC
1.8 59 km E of Port Heiden, Alaska 12:45 UTC
2.0 74 km NE of Chignik, Alaska 20:46 UTC
1.7 45 km ESE of Port Heiden, Alaska 18:12 UTC
2.5 38 km SSW of Ugashik, Alaska 13:31 UTC
1.9 70 km NE of Chignik, Alaska 12:58 UTC
2.2 73 km ENE of Chignik, Alaska 03:32 UTC
2.5 63 km NE of Chignik, Alaska 21:21 UTC
1.5 50 km E of Port Heiden, Alaska 08:28 UTC
2.2 61 km ENE of Chignik, Alaska 04:44 UTC
2.3 46 km SSW of Ugashik, Alaska 04:09 UTC
1.8 61 km E of Port Heiden, Alaska 00:39 UTC
1.6 74 km ESE of Port Heiden, Alaska 18:18 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 05:27 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.