QuakeIndex

Earthquake · reviewed by a seismologist

M 2.9md

20 km W of Winters, CA

· 5.5 km deep · released about 570 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Napa County 13 kmYolo County 29 kmSolano County 39 kmSonoma County 64 kmSutter County 68 kmColusa County 69 kmContra Costa County 74 kmMarin County 74 kmSacramento County 75 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 2.9 (md)
Depth
5.5 km below the surface
Felt
6 reports · strongest reported intensity III
Nearest
Napa County, 13 km WSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 170 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 6 people have reported feeling it to USGS.

How big was it?

This earthquake released about 570 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 27,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 19,000× the energy of this one
  3. Around the size people start to feel M 3.0 1.7× the energy of this one
  4. This earthquake M 2.9 about 570 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 38.5585, -122.1920. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Napa County, CA 13 km (8 mi) ENE of here earthquakes near Napa County
Yolo County, CA 29 km (18 mi) WSW of here earthquakes near Yolo County
Solano County, CA 39 km (24 mi) NW of here earthquakes near Solano County
Sonoma County, CA 64 km (40 mi) E of here earthquakes near Sonoma County
Sutter County, CA 68 km (42 mi) SW of here earthquakes near Sutter County
Colusa County, CA 69 km (43 mi) S of here earthquakes near Colusa County

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

Aftershocks so far

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

  1. 1.7 6 km ENE of Vallejo, CA
  2. 1.5 7 km SSW of Calistoga, CA
  3. 2.1 13 km SE of Middletown, CA
  4. 2.3 9 km E of Lower Lake, CA
  5. 2.1 7 km E of Lower Lake, CA
  6. 2.1 7 km E of Lower Lake, CA
  7. 2.3 7 km SSW of Yountville, CA
  8. 1.7 7 km W of Kenwood, CA
  9. 1.6 3 km S of Anderson Springs, CA
  10. 2.5 4 km S of Anderson Springs, CA
  11. 2.5 3 km S of Anderson Springs, CA
  12. 2.4 1 km ENE of Larkfield-Wikiup, CA
  13. 1.7 6 km ENE of Vallejo, CA
  14. 2.0 6 km SE of Napa, CA
  15. 1.8 6 km ENE of Vallejo, 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 4.4 on 2022-09-14 — it released about 200 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.