QuakeIndex

Earthquake · reviewed by a seismologist

M 1.9ml

50 km E of Chase, Alaska

Yes. A magnitude 1.9 earthquake was recorded 50 km E of Chase, Alaska, at 5:09 am AKDT on 19 September 2019 (13:09 UTC), 47 km deep.

· 47 km deep · released about 21 lb of TNT

10 km30 km60 km120 km N Matanuska-Susitna Borough 35 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
Magnitude
M 1.9 (ml)
Depth
47 km below the surface
Felt
no reports yet
Nearest
Matanuska-Susitna Borough, 35 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2584 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause 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 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 2016-04-26 — about 11,000 times the energy of this one.

Before 2016, the USGS record lists 5 earthquakes of M5 or more within 50 km:

  1. 5.8 37 km ENE of Susitna North, Alaska · 26 km S of this epicentre
  2. 5.4 54 km NE of Chase, Alaska · 41 km NNW of this epicentre
  3. 5.1 25 km ENE of Susitna North, Alaska · 33 km SSW of this epicentre
  4. 5.1 49 km NE of Chase, Alaska · 37 km NNW of this epicentre
  5. 5.0 70 km ENE of Chase, Alaska · 25 km NE 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 62.5259, -149.1391. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Matanuska-Susitna Borough, AK 35 km (21 mi) SSW earthquakes near Matanuska-Susitna Borough

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

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

  1. 1.6 34 km ENE of Susitna North, Alaska
  2. 1.5 22 km E of Susitna North, Alaska
  3. 1.6 39 km NE of Chase, Alaska
  4. 2.6 71 km S of Cantwell, Alaska
  5. 2.3 9 km E of Susitna North, Alaska
  6. 2.2 53 km NE of Susitna North, Alaska
  7. 1.5 55 km ENE of Susitna North, Alaska
  8. 1.6 29 km NE of Chase, Alaska
  9. 1.5 60 km NE of Chase, Alaska
  10. 1.7 65 km S of Cantwell, Alaska
  11. 1.6 63 km SSE of Cantwell, Alaska
  12. 1.9 64 km NE of Chase, Alaska
  13. 1.7 44 km N of Sutton-Alpine, Alaska
  14. 2.5 30 km NE of Susitna North, Alaska
  15. 1.7 38 km NE of Chase, 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.