QuakeIndex

Earthquake · reviewed by a seismologist

M 3.3ml

4 km E of Covelo, CA

· 6.2 km deep · released about 1.2 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Mendocino County 46 kmGlenn County 72 kmLake County 86 kmTehama County 90 kmTrinity County 95 kmColusa County 108 kmHumboldt County 118 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 3.3 (ml)
Depth
6.2 km below the surface
Felt
7 reports · strongest reported intensity IV
Measured shaking
intensity III (ShakeMap)
Nearest
Mendocino County, 46 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 74 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 7 people have reported feeling it to USGS.

How big was it?

This earthquake released about 1.2 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.3 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 140,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 6,200× the energy of this one
  3. Magna, Utah 2020 M 5.7 4,400× the energy of this one
  4. This earthquake M 3.3 about 1.2 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 2.5× 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.

Where

Epicentre 39.7983, -123.1990. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Mendocino County, CA 46 km (28 mi) NNE of here earthquakes near Mendocino County
Glenn County, CA 72 km (44 mi) WNW of here earthquakes near Glenn County
Lake County, CA 86 km (53 mi) NNW of here earthquakes near Lake County
Tehama County, CA 90 km (56 mi) WSW of here earthquakes near Tehama County
Trinity County, CA 95 km (59 mi) S of here earthquakes near Trinity County
Colusa County, CA 108 km (67 mi) NW of here earthquakes near Colusa County

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. 1.6 11 km ESE of Willits, CA
  2. 2.3 11 km N of Redwood Valley, CA
  3. 2.0 10 km ESE of Willits, CA
  4. 1.8 11 km N of Redwood Valley, CA
  5. 1.9 12 km ESE of Willits, CA
  6. 1.6 11 km N of Redwood Valley, CA
  7. 1.5 11 km N of Redwood Valley, CA
  8. 1.9 12 km NNW of Redwood Valley, CA
  9. 1.5 12 km NNW of Redwood Valley, CA
  10. 2.4 11 km N of Redwood Valley, CA
  11. 5.6 11 km N of Redwood Valley, CA
  12. 1.7 4 km ENE of Covelo, CA
  13. 1.8 9 km ESE of Willits, CA
  14. 1.9 22 km NW of Alder Springs, CA
  15. 1.5 20 km NW of Laytonville, 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 4.4 on 2026-01-13 — it released about 53 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.