Earthquake · automatic estimate, may change
M 3.0ml
Earthquake near Healy, AK
No earthquake was likely felt in Healy in the 24 hours to 2:21 am AKST (11:21 UTC). The last one was M 2.7, 23 km (14 mi) NNE, at 4:13 pm AKST on 3 November 2026, estimated intensity II (weak) in town. Every earthquake near Healy
This page: a magnitude 3.0 earthquake was recorded 9 km (6 mi) east of Healy, AK, at 8:16 pm AKDT on 16 May 2021 (04:16 UTC), 103 km deep. 1 person has reported feeling it to USGS. The magnitude and location are an automatic first estimate and may change.
USGS: 9 km E of Healy, Alaska
- When
- 8:16 pm AKDT on 16 May 2021 ()
- Where
- 9 km (6 mi) east of Healy, AK · earthquakes near Healy
- Magnitude
- M 3.0 (ml)
- Depth
- 103 km below the surface
- Felt
- 1 report · strongest reported intensity II
- Nearest
- Denali Borough, 65 km WSW
- Nearest mapped fault
- Park Road fault (Northern Foothills fold and thrust belt), 12 km from its surface trace — near is not the same as on
- Status
- Automatic — a machine’s first estimate, which may change
USGS · last changed by USGS · we first saw it 1938 days ago
Earthquake alerts for Healy, AK
Get a notification in this browser when USGS records an earthquake near Healy, AK. No account or email needed.
Alerts are on for .
Not a warning. An alert comes after USGS publishes a quake, usually minutes after the shaking. For early warning use ShakeAlert, through your phone's Wireless Emergency Alerts or the MyShake app.
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. In Healy, 9 km away, the estimate is intensity I (not felt). 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 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.
- Northridge, California 1994 M 6.7 350,000× the energy of this one
- Mineral, Virginia 2011 M 5.8 16,000× the energy of this one
- Magna, Utah 2020 M 5.7 11,000× the energy of this one
- 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 4.6 on 2018-01-19 — about 250 times the energy of this one.
Before 2016, the USGS record lists 3 earthquakes of M5 or more within 50 km:
- 7.1 Central Alaska · 24 km NNE of this epicentre
- 6.4 23 km ENE of Ferry, Alaska · 28 km N of this epicentre
- 6.1 35 km E of Healy, Alaska · 26 km E 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 63.8705, -148.7786. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Denali Borough, AK | 65 km (40 mi) | WSW | earthquakes near Denali Borough |
| Fairbanks North Star Borough, AK | 142 km (88 mi) | NE | earthquakes near Fairbanks North Star Borough |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
58 earthquakes have been recorded within 50 km since this one.
- 1.5 25 km ENE of Cantwell, Alaska
- 2.2 10 km WNW of Denali Park, Alaska
- 1.5 Central Alaska
- 1.6 21 km ENE of Denali Park, Alaska
- 2.1 31 km ENE of Cantwell, Alaska
- 2.3 9 km WSW of Healy, Alaska
- 2.1 13 km N of Cantwell, Alaska
- 1.5 8 km WSW of Healy, Alaska
- 1.5 12 km ESE of Healy, Alaska
- 1.7 5 km SW of Healy, Alaska
- 2.0 2 km NNW of Healy, Alaska
- 1.5 5 km NNE of Healy, Alaska
- 1.8 3 km ENE of Healy, Alaska
- 1.5 34 km E of Clear, Alaska, Alaska
- 1.6 15 km W of Healy, 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
- 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.