QuakeIndex

Earthquake · reviewed by a seismologist

M 2.9md

11 km NE of Angwin, California

· 5.8 km deep · released about 610 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Napa County 15 kmYolo County 39 kmSonoma County 52 kmSolano County 55 kmColusa County 60 kmLake County 62 kmSutter County 71 kmMarin County 74 kmContra Costa County 88 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
5.8 km below the surface
Felt
12 reports · strongest reported intensity III
Nearest
Napa County, 15 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3282 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 12 people have reported feeling it to USGS.

How big was it?

This earthquake released about 610 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 25,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 18,000× the energy of this one
  3. Around the size people start to feel M 3.0 1.6× the energy of this one
  4. This earthquake M 2.9 about 610 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 38.6432, -122.3527. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Napa County, CA 15 km (10 mi) N of here earthquakes near Napa County
Yolo County, CA 39 km (24 mi) W of here earthquakes near Yolo County
Sonoma County, CA 52 km (32 mi) ENE of here earthquakes near Sonoma County
Solano County, CA 55 km (34 mi) NW of here earthquakes near Solano County
Colusa County, CA 60 km (37 mi) S of here earthquakes near Colusa County
Lake County, CA 62 km (38 mi) SSE of here earthquakes near Lake County

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

Aftershocks so far

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

  1. 2.0 6 km WSW of Cobb, California
  2. 1.9 5 km SW of Cobb, California
  3. 1.9 4 km SSW of Cobb, California
  4. 1.7 7 km W of Cobb, California
  5. 1.6 7 km W of Cobb, California
  6. 2.6 Northern California
  7. 1.8 4 km S of Cobb, California
  8. 2.1 7 km W of Cobb, California
  9. 1.5 6 km SSE of Cobb, California
  10. 1.6 10 km WNW of Cobb, California
  11. 1.7 10 km WNW of Cobb, California
  12. 2.5 6 km W of Cobb, CA
  13. 1.8 16 km NNW of Moskowite Corner, California
  14. 2.5 5 km S of Cobb, California
  15. 2.0 5 km S of Cobb, California

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 5.0 on 2016-12-14 — it released about 1,600 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.