128 km S of Unalaska, Alaska

Yes. A magnitude 2.3 earthquake was recorded 128 km S of Unalaska, Alaska, at 12:16 pm AKDT on 26 July 2016 (20:16 UTC), 15 km deep.

2016-07-26 20:16 UTC · 15 km deep · released about 85 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: 2016-07-26 20:16 UTC
Magnitude: M 2.3 (ml)
Depth: 15 km below the surface
Felt: no reports yet
Status: Reviewed by a seismologist

USGS · last changed by USGS 1200 days ago · we first saw it 1200 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 12 km (7 mi) from the epicentre. 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 85 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.3 would have released about 32 times as much.

Mineral, Virginia 2011 M 5.8 180,000× the energy of this one
Magna, Utah 2020 M 5.7 130,000× the energy of this one
Around the size people start to feel M 3.0 11× the energy of this one
This earthquake M 2.3 about 85 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 5.4 on 2016-07-26 — about 45,000 times the energy of this one.

Before 2016, the USGS record lists 45 earthquakes of M5 or more within 50 km; the five largest:

6.5 127 km E of Nikolski, Alaska · 19 km W of this epicentre Oct 13, 2009
6.4 118 km E of Nikolski, Alaska · 28 km W of this epicentre Mar 15, 1957
6.4 123 km ESE of Nikolski, Alaska · 30 km WSW of this epicentre Oct 13, 2009
6.3 136 km ESE of Nikolski, Alaska · 16 km SW of this epicentre Jan 12, 1952
6.3 Fox Islands, Aleutian Islands, Alaska · 36 km WSW of this epicentre Jun 4, 1958

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

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Aftershocks so far

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

2.4 130 km S of Unalaska, Alaska 00:22 UTC
2.3 136 km S of Unalaska, Alaska 18:27 UTC
2.2 139 km S of Unalaska, Alaska 04:13 UTC
1.9 132 km S of Unalaska, Alaska 01:32 UTC
2.3 134 km S of Unalaska, Alaska 16:00 UTC
1.7 129 km S of Unalaska, Alaska 15:29 UTC
2.5 128 km S of Unalaska, Alaska 03:15 UTC
1.9 119 km S of Unalaska, Alaska 07:27 UTC
2.1 124 km ESE of Nikolski, Alaska 04:39 UTC
2.0 Fox Islands, Aleutian Islands, Alaska 14:48 UTC
2.3 125 km S of Unalaska, Alaska 14:33 UTC
2.1 129 km ESE of Nikolski, Alaska 12:53 UTC
2.2 132 km ESE of Nikolski, Alaska 12:44 UTC
2.0 126 km S of Unalaska, Alaska 12:35 UTC
3.2 Fox Islands, Aleutian Islands, Alaska 10:59 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 11:07 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.