QuakeIndex

Earthquake · reviewed by a seismologist

M 2.9md

8 km S of Somes Bar, CA

· 36 km deep · released about 720 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Del Norte County 66 kmHumboldt County 77 kmTrinity County 78 kmSiskiyou County 83 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 2.9 (md)
Depth
36 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Del Norte County, 66 km NW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 939 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 1 person has reported feeling it to USGS.

How big was it?

This earthquake released about 720 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 21,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 15,000× the energy of this one
  3. Around the size people start to feel M 3.0 1.3× the energy of this one
  4. This earthquake M 2.9 about 720 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.

Where

Epicentre 41.3037, -123.4595. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Del Norte County, CA 66 km (41 mi) SE of here earthquakes near Del Norte County
Humboldt County, CA 77 km (48 mi) NNE of here earthquakes near Humboldt County
Trinity County, CA 78 km (49 mi) NNW of here earthquakes near Trinity County
Siskiyou County, CA 83 km (52 mi) WSW of here earthquakes near Siskiyou County
Shasta County, CA 133 km (83 mi) WNW of here earthquakes near Shasta County

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

Aftershocks so far

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

  1. 1.9 12 km ESE of Willow Creek, CA
  2. 2.2 10 km NNW of Willow Creek, CA
  3. 1.9 16 km E of Willow Creek, CA
  4. 2.4 20 km SE of Klamath, CA
  5. 2.1 17 km ENE of Willow Creek, CA
  6. 2.0 13 km E of Willow Creek, CA
  7. 2.1 27 km ENE of Willow Creek, CA
  8. 2.6 30 km ESE of Somes Bar, CA
  9. 2.5 24 km SSE of Somes Bar, CA
  10. 2.3 13 km E of Weitchpec, CA
  11. 1.9 12 km NE of Westhaven-Moonstone, CA
  12. 2.7 33 km SSE of Somes Bar, CA
  13. 2.4 20 km ENE of Willow Creek, CA
  14. 2.3 21 km E of Willow Creek, CA
  15. 2.4 8 km SSE of Weitchpec, CA

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.

For this area

The largest earthquake within 50 km in our catalogue was M 4.3 on 2023-01-20 — it released about 100 times the energy of this one.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

On USGS

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