QuakeIndex

Earthquake · reviewed by a seismologist

M 2.9ml

4km SSE of Redwood Valley, CA

· 4.6 km deep · released about 680 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Mendocino County 32 kmLake County 40 kmGlenn County 79 kmColusa County 82 kmSonoma County 82 kmNapa County 109 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 2.9 (ml)
Depth
4.6 km below the surface
Felt
232 reports · strongest reported intensity IV
Nearest
Mendocino County, 32 km NW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1884 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 232 people have reported feeling it to USGS.

How big was it?

This earthquake released about 680 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 22,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 16,000× the energy of this one
  3. Around the size people start to feel M 3.0 1.4× the energy of this one
  4. This earthquake M 2.9 about 680 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 39.2322, -123.1817. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Mendocino County, CA 32 km (20 mi) SE of here earthquakes near Mendocino County
Lake County, CA 40 km (25 mi) WNW of here earthquakes near Lake County
Glenn County, CA 79 km (49 mi) WSW of here earthquakes near Glenn County
Colusa County, CA 82 km (51 mi) W of here earthquakes near Colusa County
Sonoma County, CA 82 km (51 mi) NNW of here earthquakes near Sonoma County
Napa County, CA 109 km (68 mi) NW of here earthquakes near Napa County

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

Aftershocks so far

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

  1. 1.8 6km N of Lake Pillsbury, CA
  2. 1.8 16km NE of Upper Lake, CA
  3. 1.9 14km SE of Lake Pillsbury, CA
  4. 1.5 10km SE of Willits, CA
  5. 1.9 10km SE of Willits, CA
  6. 1.9 5km SSE of Redwood Valley, CA
  7. 1.9 6km SSE of Redwood Valley, CA
  8. 1.5 16km E of Navarro Head, CA
  9. 1.9 8km NNW of Redwood Valley, CA
  10. 2.0 12km WNW of Lake Pillsbury, CA
  11. 1.9 4km NNW of Lake Pillsbury, CA
  12. 1.8 6km E of Willits, CA
  13. 1.8 9km NNW of Redwood Valley, CA
  14. 2.2 7km E of Willits, CA
  15. 1.7 10km SW of Ukiah, 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 1,900 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.