QuakeIndex

Earthquake · reviewed by a seismologist

M 2.7ml

Earthquake near Kalifornsky, AK

No earthquake was likely felt in Kalifornsky in the 24 hours to 11:21 am AKST (20:21 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 2.7 earthquake was recorded 29 km (18 mi) south-southeast of Kalifornsky, AK, at 9:12 am AKDT on 28 April 2018 (17:12 UTC), 65 km deep.

USGS: 17 km ESE of Clam Gulch, Alaska

9:12 am AKDT, Apr 28, 2018 · · 65 km deep · released about 340 lb of TNT

10 km30 km60 km120 km N Kenai Peninsula Borough 71 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
9:12 am AKDT on 28 April 2018 ()
Where
29 km (18 mi) south-southeast of Kalifornsky, AK · earthquakes near Kalifornsky
Magnitude
M 2.7 (ml)
Depth
65 km below the surface
Felt
no reports yet
Nearest
Kenai Peninsula Borough, 71 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1187 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, 29 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: Cohoe.

How big was it?

This earthquake released about 340 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 45,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 32,000× the energy of this one
  3. Around the size people start to feel M 3.0 2.8× the energy of this one
  4. This earthquake M 2.7 about 340 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

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

Before 2016, the USGS record lists 6 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.0 31 km S of Funny River, Alaska · 25 km ENE of this epicentre
  2. 6.0 6 km SSE of Fox River, Alaska · 43 km SSE of this epicentre
  3. 5.9 13 km N of Fox River, Alaska · 23 km SSE of this epicentre
  4. 5.5 13 km NW of Happy Valley, Alaska · 49 km WSW of this epicentre
  5. 5.2 17 km WNW of Clam Gulch, Alaska · 35 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 60.1770, -151.0957. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Kenai Peninsula Borough, AK 71 km (44 mi) WNW earthquakes near Kenai Peninsula Borough
Anchorage Municipality, AK 148 km (92 mi) NE earthquakes near Anchorage Municipality

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

Aftershocks so far

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

  1. 1.6 12 km SW of Salamatof, Alaska
  2. 2.2 12 km NE of Ridgeway, Alaska
  3. 1.8 4 km SSW of Salamatof, Alaska
  4. 1.6 4 km SE of Clam Gulch, Alaska
  5. 3.0 22 km N of Fox River, Alaska
  6. 1.6 7 km WSW of Soldotna, Alaska
  7. 1.5 2 km NE of Ninilchik, Alaska
  8. 2.1 14 km SE of Fox River, Alaska
  9. 1.9 16 km ESE of Kasilof, Alaska
  10. 2.3 11 km NNW of Fritz Creek, Alaska
  11. 2.6 15 km ESE of Ninilchik, Alaska
  12. 1.5 17 km WNW of Kalifornsky, Alaska
  13. 1.6 14 km SE of Kasilof, Alaska
  14. 1.5 Kenai Peninsula, Alaska
  15. 1.7 12 km W of Fox River, 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.