QuakeIndex

Earthquake · reviewed by a seismologist

M 4.4mw

9 km ESE of Willits, CA

· 8.5 km deep · released about 64 tons of TNT

10 km30 km60 km120 km N Mendocino County 17 kmLake County 54 kmGlenn County 77 kmColusa County 90 kmSonoma County 100 kmTehama 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 4.4 (mw)
Depth
8.5 km below the surface
Felt
414 reports · strongest reported intensity V
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, 17 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 5 days ago

This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon. 414 people have reported feeling it to USGS.

How big was it?

This earthquake released about 64 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.4 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 2,600× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 120× the energy of this one
  3. Magna, Utah 2020 M 5.7 83× the energy of this one
  4. This earthquake M 4.4 about 64 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 130× 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 39.3922, -123.2513. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Mendocino County, CA 17 km (11 mi) ESE of here earthquakes near Mendocino County
Lake County, CA 54 km (33 mi) NW of here earthquakes near Lake County
Glenn County, CA 77 km (48 mi) WSW of here earthquakes near Glenn County
Colusa County, CA 90 km (56 mi) WNW of here earthquakes near Colusa County
Sonoma County, CA 100 km (62 mi) NNW of here earthquakes near Sonoma County
Tehama County, CA 119 km (74 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

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

  1. 1.8 7 km N of Lake Pillsbury, CA
  2. 1.6 7 km N of Lake Pillsbury, CA
  3. 1.7 9 km NNE of Brooktrails, CA
  4. 1.9 14 km E of Willits, CA
  5. 2.2 12 km SSE of Laytonville, CA
  6. 1.7 3 km SSE of Redwood Valley, CA
  7. 2.1 10 km NNE of Talmage, CA
  8. 2.0 3 km SSE of Redwood Valley, CA
  9. 1.9 10 km NNE of Talmage, CA
  10. 2.3 6 km SSE of Willits, CA
  11. 2.0 13 km W of Alder Springs, CA
  12. 1.8 2 km S of Redwood Valley, CA
  13. 2.1 15 km N of Brooktrails, CA
  14. 2.2 2 km S of Redwood Valley, CA
  15. 1.6 15 km N 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 5.1 on 2016-08-10 — it released about 10 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.