QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

9 km SSW of Arbuckle, CA

· 14 km deep · released about 14 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Colusa County 30 kmYolo County 33 kmSutter County 34 kmNapa County 53 kmLake County 60 kmYuba County 73 kmSolano County 76 kmGlenn County 79 kmSacramento County 84 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
14 km below the surface
Felt
no reports yet
Nearest
Colusa County, 30 km NNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 606 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 14 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 1,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 790,000× the energy of this one
  3. Around the size people start to feel M 3.0 70× the energy of this one
  4. This earthquake M 1.8 about 14 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 38.9405, -122.0815. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Colusa County, CA 30 km (18 mi) SSE of here earthquakes near Colusa County
Yolo County, CA 33 km (20 mi) NNW of here earthquakes near Yolo County
Sutter County, CA 34 km (21 mi) WSW of here earthquakes near Sutter County
Napa County, CA 53 km (33 mi) NNE of here earthquakes near Napa County
Lake County, CA 60 km (37 mi) ESE of here earthquakes near Lake County
Yuba County, CA 73 km (46 mi) WSW of here earthquakes near Yuba County

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

Aftershocks so far

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

  1. 2.1 13 km SE of Middletown, CA
  2. 2.2 9 km SSW of South Yuba City, CA
  3. 2.3 9 km E of Lower Lake, CA
  4. 2.1 7 km E of Lower Lake, CA
  5. 2.1 7 km E of Lower Lake, CA
  6. 3.1 9 km ENE of Colusa, CA
  7. 2.6 12 km SE of Middletown, CA
  8. 1.7 20 km W of Winters, CA
  9. 1.6 18 km WNW of Winters, CA
  10. 2.0 13 km ESE of Angwin, CA
  11. 2.9 20 km W of Winters, CA
  12. 1.8 13 km ESE of Angwin, CA
  13. 1.7 11 km ESE of Hidden Valley Lake, CA
  14. 2.0 10 km ENE of Hidden Valley Lake, CA
  15. 1.5 10 km ENE of Hidden Valley Lake, 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.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.