QuakeIndex

Earthquake · reviewed by a seismologist

M 3.5ml

Earthquake near Kalifornsky, AK

No earthquake was likely felt in Kalifornsky in the 24 hours to 7:03 am AKST (16:03 UTC). The last one was M 4.3, 31 km (20 mi) SE, at 2:30 am AKST on 1 November 2026, estimated intensity II (weak) in town; 115 felt reports to USGS. Every earthquake near Kalifornsky

This page: a magnitude 3.5 earthquake was recorded 46 km (29 mi) south-southwest of Kalifornsky, AK, at 6:24 am AKDT on 10 August 2023 (14:24 UTC), 65 km deep. 14 people have reported feeling it to USGS.

USGS: 8 km ESE of Ninilchik, Alaska

6:24 am AKDT, Aug 10, 2023 · · 65 km deep · released about 2.7 tons of TNT

Every earthquake near Kalifornsky Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Kenai Peninsula Borough 59 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
6:24 am AKDT on 10 August 2023 ()
Where
46 km (29 mi) south-southwest of Kalifornsky, AK · earthquakes near Kalifornsky
Magnitude
M 3.5 (ml)
Depth
65 km below the surface
Felt
14 reports · strongest reported intensity III
Nearest
Kenai Peninsula Borough, 59 km NW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1123 days ago

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 Kalifornsky, 46 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.

How big was it?

This earthquake released about 2.7 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.5 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 63,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 2,800× the energy of this one
  3. Magna, Utah 2020 M 5.7 2,000× the energy of this one
  4. This earthquake M 3.5 about 2.7 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 5.6× more

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 5.3 on 2017-05-07 — about 500 times the energy of this one.

Before 2016, the USGS record lists 8 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.2 16 km WNW of Happy Valley, Alaska · 26 km W of this epicentre
  2. 6.0 6 km SSE of Fox River, Alaska · 41 km SE of this epicentre
  3. 5.9 13 km N of Fox River, Alaska · 31 km E of this epicentre
  4. 5.8 23 km WNW of Happy Valley, Alaska · 33 km W of this epicentre
  5. 5.6 7 km SE of Fritz Creek, Alaska · 42 km SSE 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 60.0201, -151.5254. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Kenai Peninsula Borough, AK 59 km (36 mi) NW earthquakes near Kenai Peninsula Borough

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

Aftershocks so far

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

  1. 1.7 5 km ENE of Kasilof, Alaska
  2. 1.5 16 km NNW of Ninilchik, Alaska
  3. 1.8 7 km NW of Nikolaevsk, Alaska
  4. 1.5 11 km W of Clam Gulch, Alaska
  5. 1.7 6 km ESE of Ninilchik, Alaska
  6. 1.5 17 km SSE of Clam Gulch, Alaska
  7. 1.5 17 km NW of Happy Valley, Alaska
  8. 1.5 9 km W of Ninilchik, Alaska
  9. 1.6 13 km NNE of Nikolaevsk, Alaska
  10. 1.7 6 km WNW of Ninilchik, Alaska
  11. 1.7 19 km WNW of Kalifornsky, Alaska
  12. 1.5 Kenai Peninsula, Alaska
  13. 1.8 17 km ESE of Kasilof, Alaska
  14. 2.0 17 km NW of Ninilchik, Alaska
  15. 1.9 10 km SSE of Kasilof, 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.