QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

3km NW of Redwood Valley, CA

· 4.1 km deep · released about 16 lb of TNT

10 km30 km60 km120 km N Mendocino County 25 kmLake County 46 kmGlenn County 79 kmColusa County 86 kmSonoma County 88 kmNapa 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 1.8 (md)
Depth
4.1 km below the surface
Felt
no reports yet
Nearest
Mendocino County, 25 km NW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2963 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 5.8 970,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 680,000× the energy of this one
  3. Around the size people start to feel M 3.0 61× 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 39.2837, -123.2230. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Mendocino County, CA 25 km (16 mi) SE of here earthquakes near Mendocino County
Lake County, CA 46 km (28 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 86 km (53 mi) W of here earthquakes near Colusa County
Sonoma County, CA 88 km (55 mi) NNW of here earthquakes near Sonoma County
Napa County, CA 116 km (72 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

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

  1. 1.6 10km SSE of Laytonville, CA
  2. 1.9 7km NE of Brooktrails, CA
  3. 2.2 6km ESE of Willits, CA
  4. 3.8 6km ENE of Willits, CA
  5. 1.5 14km SSE of Talmage, CA
  6. 1.8 12km SE of Laytonville, CA
  7. 2.0 8km W of Upper Lake, CA
  8. 1.8 3km NW of Lake Pillsbury, CA
  9. 2.2 4km SW of Talmage, CA
  10. 2.1 6km SE of Redwood Valley, CA
  11. 1.9 8km SSE of Lake Pillsbury, CA
  12. 1.5 15km SW of Lakeport, CA
  13. 1.7 15km NE of Nice, CA
  14. 1.8 8km NNW of Redwood Valley, CA
  15. 2.1 14km NNE of Lake Pillsbury, 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 83,000 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.