QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

23 km N of Lake Pillsbury, CA

· 15 km deep · released about 16 lb of TNT

10 km30 km60 km120 km N Mendocino County 43 kmGlenn County 51 kmLake County 60 kmColusa County 81 kmTehama County 87 kmTrinity County 116 kmButte County 120 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
15 km below the surface
Felt
no reports yet
Nearest
Mendocino County, 43 km WSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 362 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 39.6102, -123.0018. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Mendocino County, CA 43 km (27 mi) ENE of here earthquakes near Mendocino County
Glenn County, CA 51 km (32 mi) W of here earthquakes near Glenn County
Lake County, CA 60 km (37 mi) NNW of here earthquakes near Lake County
Colusa County, CA 81 km (51 mi) NW of here earthquakes near Colusa County
Tehama County, CA 87 km (54 mi) SW of here earthquakes near Tehama County
Trinity County, CA 116 km (72 mi) S of here earthquakes near Trinity County

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

Aftershocks so far

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

  1. 1.5 11 km ESE of Willits, CA
  2. 1.5 10 km NNE of Talmage, CA
  3. 3.8 11 km ESE of Willits, CA
  4. 1.7 9 km ESE of Willits, CA
  5. 4.4 9 km ESE of Willits, CA
  6. 1.9 15 km N of Laytonville, CA
  7. 1.6 13 km NNW of Lake Pillsbury, CA
  8. 1.8 8 km SE of Lake Pillsbury, CA
  9. 1.5 6 km ESE of Lake Pillsbury, CA
  10. 1.6 4 km SSE of Redwood Valley, CA
  11. 1.7 6 km ENE of Brooktrails, CA
  12. 1.5 8 km SE of Lake Pillsbury, CA
  13. 2.1 9 km SSE of Laytonville, CA
  14. 1.7 9 km NE of Talmage, CA
  15. 1.9 10 km NW of Redwood Valley, 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.