QuakeIndex

Earthquake · reviewed by a seismologist

M 4.2mw

11km ESE of Willits, CA

· 8.2 km deep · released about 32 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Mendocino County 19 kmLake County 51 kmGlenn County 77 kmColusa County 89 kmSonoma County 97 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 4.2 (mw)
Depth
8.2 km below the surface
Felt
313 reports · strongest reported intensity IV
Measured shaking
intensity V (ShakeMap)
USGS impact alert
green
Tsunami
USGS flagged this event for tsunami evaluation. Follow tsunami.gov for official messages.
Nearest
Mendocino County, 19 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 257 days ago

This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon. 313 people have reported feeling it to USGS.

How big was it?

This earthquake released about 32 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.2 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 5,200× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 230× the energy of this one
  3. Magna, Utah 2020 M 5.7 170× the energy of this one
  4. This earthquake M 4.2 about 32 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 68× 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 39.3605, -123.2458. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Mendocino County, CA 19 km (12 mi) ESE of here earthquakes near Mendocino County
Lake County, CA 51 km (32 mi) WNW of here earthquakes near Lake County
Glenn County, CA 77 km (48 mi) WSW of here earthquakes near Glenn County
Colusa County, CA 89 km (55 mi) WNW of here earthquakes near Colusa County
Sonoma County, CA 97 km (60 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. 1.7 10km ESE of Willits, CA
  2. 1.6 11km NNW of Redwood Valley, CA
  3. 1.9 11km ESE of Willits, CA
  4. 1.6 11km ESE of Willits, CA
  5. 1.6 11km NNW of Redwood Valley, CA
  6. 2.0 10km NNW of Redwood Valley, CA
  7. 3.5 10km NNW of Redwood Valley, CA
  8. 2.6 11km NNW of Redwood Valley, CA
  9. 1.6 8km W of Redwood Valley, CA
  10. 2.1 17km S of Talmage, CA
  11. 2.3 15km NE of Upper Lake, CA
  12. 1.7 18km S of Talmage, CA
  13. 1.5 11km NNW of Redwood Valley, CA
  14. 1.6 11km NNW of Redwood Valley, CA
  15. 1.8 10km ESE of Willits, 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 20 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.