QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

5km SSW of Redwood Valley, CA

· 0.2 km deep · released about 16 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Mendocino County 29 kmLake County 44 kmSonoma County 82 kmGlenn County 83 kmColusa County 86 kmNapa County 112 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 1.8 (md)
Depth
0.2 km below the surface
Felt
no reports yet
Nearest
Mendocino County, 29 km NW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2032 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

How big was it?

This earthquake released about 16 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 930,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 660,000× the energy of this one
  3. Around the size people start to feel M 3.0 59× the energy of this one
  4. This earthquake M 1.8 about 16 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 39.2242, -123.2310. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Mendocino County, CA 29 km (18 mi) SE of here earthquakes near Mendocino County
Lake County, CA 44 km (27 mi) WNW of here earthquakes near Lake County
Sonoma County, CA 82 km (51 mi) NNW of here earthquakes near Sonoma County
Glenn County, CA 83 km (51 mi) WSW of here earthquakes near Glenn County
Colusa County, CA 86 km (53 mi) W of here earthquakes near Colusa County
Napa County, CA 112 km (69 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

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

  1. 1.8 20km NNW of Boonville, CA
  2. 1.7 7km E of Willits, CA
  3. 1.9 13km SE of Talmage, CA
  4. 2.8 13km SE of Talmage, CA
  5. 2.8 13km SE of Talmage, CA
  6. 1.6 10km SE of Laytonville, CA
  7. 2.4 10km SE of Willits, CA
  8. 1.6 20km SSW of Willits, CA
  9. 2.8 21km SSW of Willits, CA
  10. 4.0 21km SSW of Willits, CA
  11. 1.5 22km E of Navarro Head, CA
  12. 2.0 13km WNW of Lake Pillsbury, CA
  13. 2.7 13km W of Lake Pillsbury, CA
  14. 1.9 10km ESE of Willits, 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 80,000 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.