QuakeIndex

Earthquake · reviewed by a seismologist

M 4.1mw

19km NW of Covelo, CA

· 7.4 km deep · released about 20 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Mendocino County 51 kmTrinity County 88 kmGlenn County 93 kmHumboldt County 100 kmTehama County 105 kmLake County 105 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 4.1 (mw)
Depth
7.4 km below the surface
Felt
21 reports · strongest reported intensity IV
Measured shaking
intensity IV (ShakeMap)
USGS impact alert
green
Nearest
Mendocino County, 51 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1717 days ago

This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon. 21 people have reported feeling it to USGS.

How big was it?

This earthquake released about 20 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 8,500× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 380× the energy of this one
  3. Magna, Utah 2020 M 5.7 270× the energy of this one
  4. This earthquake M 4.1 about 20 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 42× 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 39.8938, -123.4245. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Mendocino County, CA 51 km (32 mi) N of here earthquakes near Mendocino County
Trinity County, CA 88 km (55 mi) SSW of here earthquakes near Trinity County
Glenn County, CA 93 km (58 mi) WNW of here earthquakes near Glenn County
Humboldt County, CA 100 km (62 mi) SSE of here earthquakes near Humboldt County
Tehama County, CA 105 km (65 mi) WSW of here earthquakes near Tehama County
Lake County, CA 105 km (65 mi) NNW of here earthquakes near Lake County

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

Aftershocks so far

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

  1. 1.9 23km NE of Redway, CA
  2. 1.7 9km W of Covelo, CA
  3. 1.9 6km E of Covelo, CA
  4. 2.0 23km NW of Alder Springs, CA
  5. 2.3 5km E of Covelo, CA
  6. 1.7 5km E of Covelo, CA
  7. 2.1 7km W of Redway, CA
  8. 1.9 5km ENE of Covelo, CA
  9. 1.8 6km E of Covelo, CA
  10. 2.0 5km ENE of Covelo, CA
  11. 1.9 5km ENE of Covelo, CA
  12. 1.7 6km E of Covelo, CA
  13. 2.9 6km E of Covelo, CA
  14. 1.8 8km SSE of Laytonville, CA
  15. 1.8 7km ENE of Covelo, 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 2017-12-14 — it released about 1.9 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.