QuakeIndex

Earthquake · reviewed by a seismologist

M 3.8mw

11km ESE of Willits, CA

· 7.5 km deep · released about 7.3 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Mendocino County 19 kmLake County 52 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 3.8 (mw)
Depth
7.5 km below the surface
Felt
142 reports · strongest reported intensity IV
Measured shaking
intensity V (ShakeMap)
USGS impact alert
green
Nearest
Mendocino County, 19 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2098 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 142 people have reported feeling it to USGS.

How big was it?

This earthquake released about 7.3 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.8 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 23,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 1,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 730× the energy of this one
  4. This earthquake M 3.8 about 7.3 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 15× 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 39.3658, -123.2443. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Mendocino County, CA 19 km (12 mi) ESE of here earthquakes near Mendocino County
Lake County, CA 52 km (32 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 89 km (55 mi) WNW of here earthquakes near Colusa County
Sonoma County, CA 97 km (61 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

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

  1. 4.4 13km W of Lakeport, CA
  2. 1.6 14km SSE of Covelo, CA
  3. 1.6 8km WSW of Covelo, CA
  4. 1.9 10km ESE of Willits, CA
  5. 2.8 13km W of Lakeport, CA
  6. 2.1 6km NW of Lake Pillsbury, CA
  7. 2.9 16km W of Ukiah, CA
  8. 1.5 6km E of Redwood Valley, CA
  9. 2.3 7km SSE of Boonville, CA
  10. 1.6 2km SW of Redwood Valley, CA
  11. 1.6 10km NNE of Brooktrails, CA
  12. 1.9 11km E of Boonville, CA
  13. 2.2 10km SE of Willits, CA
  14. 1.6 18km NE of Upper Lake, CA
  15. 1.5 5km SSW of Boonville, 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 89 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.