QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

22km SW of Arbuckle, CA

· 18 km deep · released about 17 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Colusa County 33 kmYolo County 37 kmNapa County 42 kmSutter County 49 kmLake County 51 kmSonoma County 72 kmSolano County 73 kmGlenn County 82 kmYuba County 89 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
18 km below the surface
Felt
no reports yet
Nearest
Colusa County, 33 km N
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2585 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 17 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 5.8 900,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 640,000× the energy of this one
  3. Around the size people start to feel M 3.0 57× the energy of this one
  4. This earthquake M 1.8 about 17 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 38.8792, -122.2375. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Colusa County, CA 33 km (21 mi) S of here earthquakes near Colusa County
Yolo County, CA 37 km (23 mi) NW of here earthquakes near Yolo County
Napa County, CA 42 km (26 mi) N of here earthquakes near Napa County
Sutter County, CA 49 km (31 mi) WSW of here earthquakes near Sutter County
Lake County, CA 51 km (32 mi) ESE of here earthquakes near Lake County
Sonoma County, CA 72 km (44 mi) ENE of here earthquakes near Sonoma County

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

Aftershocks so far

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

  1. 1.9 3km NW of The Geysers, CA
  2. 1.9 3km NNW of The Geysers, CA
  3. 1.6 3km SE of The Geysers, CA
  4. 1.6 2km NW of The Geysers, CA
  5. 1.9 3km NNW of The Geysers, CA
  6. 1.6 3km NW of The Geysers, CA
  7. 2.0 3km SSE of The Geysers, CA
  8. 1.9 3km WSW of Anderson Springs, CA
  9. 2.1 1km ESE of The Geysers, CA
  10. 1.7 14km E of Angwin, CA
  11. 1.8 14km E of Angwin, CA
  12. 1.9 2km NW of The Geysers, CA
  13. 2.0 4km NNW of The Geysers, CA
  14. 1.7 14km E of Angwin, CA
  15. 1.6 4km SW of Anderson Springs, 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 4.2 on 2018-01-18 — it released about 3,800 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.