QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

4km E of Covelo, CA

· 6.6 km deep · released about 37 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Mendocino County 45 kmGlenn County 71 kmLake County 85 kmTehama County 90 kmTrinity County 95 kmColusa County 107 kmHumboldt County 119 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 2.1 (md)
Depth
6.6 km below the surface
Felt
no reports yet
Nearest
Mendocino County, 45 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1375 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

How big was it?

This earthquake released about 37 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 410,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 290,000× the energy of this one
  3. Around the size people start to feel M 3.0 26× the energy of this one
  4. This earthquake M 2.1 about 37 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 39.7913, -123.1950. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Mendocino County, CA 45 km (28 mi) NNE of here earthquakes near Mendocino County
Glenn County, CA 71 km (44 mi) WNW of here earthquakes near Glenn County
Lake County, CA 85 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 107 km (66 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

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

  1. 2.1 40km NE of Covelo, CA
  2. 1.8 7km ENE of Brooktrails, CA
  3. 1.8 12km ESE of Laytonville, CA
  4. 2.9 27km NNW of Laytonville, CA
  5. 1.8 11km ESE of Willits, CA
  6. 2.0 27km NNW of Laytonville, CA
  7. 2.3 27km NNW of Laytonville, CA
  8. 2.0 8km SSE of Laytonville, CA
  9. 2.0 4km NE of Lake Pillsbury, CA
  10. 2.0 40km NE of Covelo, CA
  11. 2.4 11km W of Lake Pillsbury, CA
  12. 1.7 2km E of Willits, CA
  13. 1.7 11km N of Brooktrails, CA
  14. 2.4 2km ENE of Willits, CA
  15. 2.5 15km W of Brooktrails, 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 2019-04-29 — it released about 2,500 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.