QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1ml

6km SE of Laytonville, CA

· 7.7 km deep · released about 1,200 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Mendocino County 23 kmLake County 84 kmGlenn County 89 kmTrinity County 115 kmColusa County 115 kmTehama County 116 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 3.1 (ml)
Depth
7.7 km below the surface
Felt
39 reports · strongest reported intensity IV
Nearest
Mendocino County, 23 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2311 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 39 people have reported feeling it to USGS.

How big was it?

This earthquake released about 1,200 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 290,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 13,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 9,100× the energy of this one
  4. This earthquake M 3.1 about 1,200 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.2× 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 39.6403, -123.4410. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Mendocino County, CA 23 km (14 mi) N of here earthquakes near Mendocino County
Lake County, CA 84 km (52 mi) NW of here earthquakes near Lake County
Glenn County, CA 89 km (55 mi) W of here earthquakes near Glenn County
Trinity County, CA 115 km (72 mi) SSW of here earthquakes near Trinity County
Colusa County, CA 115 km (72 mi) WNW of here earthquakes near Colusa County
Tehama County, CA 116 km (72 mi) WSW of here earthquakes near Tehama County

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

Aftershocks so far

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

  1. 2.1 20km NNW of Lake Pillsbury, CA
  2. 1.6 9km NNW of Redwood Valley, CA
  3. 1.8 9km E of Redwood Valley, CA
  4. 2.0 20km NE of Brooktrails, CA
  5. 1.9 21km NNE of Rockport, CA
  6. 2.2 21km NNE of Rockport, CA
  7. 1.6 8km NNE of Redwood Valley, CA
  8. 1.9 20km NNW of Lake Pillsbury, CA
  9. 1.9 18km NW of Lake Pillsbury, CA
  10. 2.2 20km NNW of Lake Pillsbury, CA
  11. 2.5 6km NNE of Fort Bragg, CA
  12. 1.7 11km SE of Laytonville, CA
  13. 1.7 9km NNW of Redwood Valley, CA
  14. 2.3 8km NNW of Redwood Valley, CA
  15. 1.9 14km N of Rockport, 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 78 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.