QuakeIndex

explosion · reviewed by a seismologist

M 1.9ml

Earthquake near Healy, AK

No earthquake was likely felt in Healy in the 24 hours to 4:39 am AKST (13:39 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

No: USGS classifies this as a explosion, not an earthquake. A magnitude 1.9 explosion was recorded 8 km (5 mi) north of Healy, AK, at 4:23 pm AKDT on 21 October 2019 (00:23 UTC), less than 1 km deep.

USGS: 7 km N of Healy, Alaska

4:23 pm AKDT, Oct 21, 2019 · · 0.0 km deep · released about 21 lb of TNT

Every earthquake near Healy Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Denali Borough 60 km
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
4:23 pm AKDT on 21 October 2019 ()
Where
8 km (5 mi) north of Healy, AK · earthquakes near Healy
Magnitude
M 1.9 (ml)
Depth
0.0 km below the surface
Felt
no reports yet
Nearest
Denali Borough, 60 km WSW
Nearest mapped fault
Park Road fault (Northern Foothills fold and thrust belt), 21 km from its surface trace — near is not the same as on
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2563 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 15 km (9 mi) from the epicentre. In Healy, 8 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: Healy 8 km, intensity II. Estimated for each town centre; each link is that town's own record.

USGS catalogues this as explosion, not an earthquake.

How big was it?

This earthquake released about 21 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 710,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 500,000× the energy of this one
  3. Around the size people start to feel M 3.0 45× the energy of this one
  4. This earthquake M 1.9 about 21 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 11,000 times the energy of this one.

Before 2016, the USGS record lists 4 earthquakes of M5 or more within 50 km:

  1. 7.1 Central Alaska · 24 km NE of this epicentre
  2. 6.4 23 km ENE of Ferry, Alaska · 24 km NNE of this epicentre
  3. 6.1 35 km E of Healy, Alaska · 34 km E of this epicentre
  4. 5.0 30 km W of Ferry, Alaska · 41 km WNW 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 63.9271, -148.9382. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Denali Borough, AK 60 km (37 mi) WSW earthquakes near Denali Borough
Fairbanks North Star Borough, AK 144 km (89 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

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

  1. 1.6 9 km NE of McKinley Park, Alaska
  2. 1.5 11 km NNW of Cantwell, Alaska
  3. 2.1 7 km NNE of Healy, Alaska
  4. 1.8 13 km NE of Cantwell, Alaska
  5. 2.1 7 km NNE of Healy, Alaska
  6. 2.8 24 km ENE of McKinley Park, Alaska
  7. 1.6 10 km NE of McKinley Park, Alaska
  8. 2.4 8 km N of Healy, Alaska
  9. 1.7 8 km NNE of Healy, Alaska
  10. 2.2 15 km W of Healy, Alaska
  11. 1.8 16 km WSW of Healy, Alaska
  12. 1.5 13 km WSW of Healy, Alaska
  13. 1.5 7 km N of Healy, Alaska
  14. 1.7 18 km NNE of Cantwell, Alaska
  15. 1.7 18 km W of McKinley Park, 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

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