QuakeIndex

ice quake · automatic estimate, may change

M 1.9ml

Earthquake near Lazy Mountain, AK

No earthquake was likely felt in Lazy Mountain in the 24 hours to 6:35 am AKST (15:35 UTC). The last one was M 4.4, 105 km (65 mi) ENE, at 11:11 am AKDT on 30 October 2026, estimated intensity II (weak) in town; 54 felt reports to USGS. Every earthquake near Lazy Mountain

No: USGS classifies this as a ice quake, not an earthquake. A magnitude 1.9 ice quake was recorded 17 km (11 mi) east of Lazy Mountain, AK, at 1:50 am AKDT on 11 September 2020 (09:50 UTC), 11 km deep.

USGS: 17 km E of Lazy Mountain, Alaska

81 km (50 mi) ENE of Anchorage, AK

1:50 am AKDT, Sep 11, 2020 · · 11 km deep · released about 21 lb of TNT

Every earthquake near Lazy Mountain Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Anchorage Municipality 59 kmMatanuska-Susitna Borough 87 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
1:50 am AKDT on 11 September 2020 ()
Where
17 km (11 mi) east of Lazy Mountain, AK · earthquakes near Lazy Mountain
Magnitude
M 1.9 (ml)
Depth
11 km below the surface
Felt
no reports yet
Nearest
Anchorage Municipality, 59 km SW
Nearest mapped fault
Castle Mountain fault, 24 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 2254 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 10 km (6 mi) from the epicentre. In Lazy Mountain, 17 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.

Earthquakes near other towns within 30 km: Sutton-Alpine, Butte, Palmer, Farm Loop.

USGS catalogues this as ice quake, 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 2018-01-27 — 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. 6.8 31 km SSW of Glacier View, Alaska · 45 km E of this epicentre
  2. 5.8 14 km NNE of Fishhook, Alaska · 38 km NW of this epicentre
  3. 5.2 48 km S of Glacier View, Alaska · 49 km ESE of this epicentre
  4. 5.0 4 km N of Chickaloon, Alaska · 27 km NNE 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 61.6038, -148.6197. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Anchorage Municipality, AK 59 km (37 mi) SW earthquakes near Anchorage Municipality
Matanuska-Susitna Borough, AK 87 km (54 mi) NNW earthquakes near Matanuska-Susitna Borough

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

Aftershocks so far

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

  1. 1.5 22 km N of Sutton-Alpine, Alaska
  2. 1.5 19 km NNE of Chickaloon, Alaska
  3. 1.5 30 km SE of Knik River, Alaska
  4. 1.6 28 km SE of Chickaloon, Alaska
  5. 1.7 22 km NE of Chickaloon, AK
  6. 1.6 14 km N of Chickaloon, Alaska
  7. 1.6 13 km N of Chickaloon, Alaska
  8. 1.6 25 km NNE of Fishhook, Alaska
  9. 1.6 Southern Alaska
  10. 2.1 19 km ESE of Chickaloon, Alaska
  11. 1.9 23 km NNW of Chickaloon, Alaska
  12. 1.7 11 km SSE of Chickaloon, Alaska
  13. 2.1 17 km E of Chickaloon, Alaska
  14. 1.7 14 km E of Chickaloon, Alaska
  15. 1.5 7 km SSE of Sutton-Alpine, 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.