QuakeIndex

Earthquake · reviewed by a seismologist

M 2.8md

7km ESE of Willits, CA

· 6.8 km deep · released about 490 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Mendocino County 15 kmLake County 55 kmGlenn County 78 kmColusa County 92 kmSonoma County 101 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 2.8 (md)
Depth
6.8 km below the surface
Felt
14 reports · strongest reported intensity III
Nearest
Mendocino County, 15 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1857 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 14 people have reported feeling it to USGS.

How big was it?

This earthquake released about 490 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 31,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 22,000× the energy of this one
  3. Around the size people start to feel M 3.0 1.9× the energy of this one
  4. This earthquake M 2.8 about 490 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 39.3925, -123.2725. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Mendocino County, CA 15 km (10 mi) ESE of here earthquakes near Mendocino County
Lake County, CA 55 km (34 mi) NW of here earthquakes near Lake County
Glenn County, CA 78 km (49 mi) WSW of here earthquakes near Glenn County
Colusa County, CA 92 km (57 mi) WNW of here earthquakes near Colusa County
Sonoma County, CA 101 km (63 mi) NNW of here earthquakes near Sonoma County
Tehama County, CA 121 km (75 mi) SW of here earthquakes near Tehama County

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

Aftershocks so far

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

  1. 1.9 13km W of Alder Springs, CA
  2. 2.1 13km W of Alder Springs, CA
  3. 2.1 12km W of Alder Springs, CA
  4. 1.8 12km W of Alder Springs, CA
  5. 2.8 12km W of Alder Springs, CA
  6. 2.6 12km WNW of Alder Springs, CA
  7. 3.7 12km W of Alder Springs, CA
  8. 2.0 12km W of Alder Springs, CA
  9. 2.1 12km W of Alder Springs, CA
  10. 2.7 11km W of Alder Springs, CA
  11. 2.1 13km WNW of Alder Springs, CA
  12. 2.5 12km W of Alder Springs, CA
  13. 1.8 2km ESE of Redwood Valley, CA
  14. 1.6 6km W of Laytonville, CA
  15. 2.0 12km WNW of Alder Springs, 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 5.1 on 2016-08-10 — it released about 2,600 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.