QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

3 km SSE of Rio Vista, California

· -0.0 km deep · released about 37 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Solano County 27 kmContra Costa County 34 kmSan Joaquin County 42 kmSacramento County 45 kmAlameda County 58 kmYolo County 63 kmNapa County 70 kmStanislaus County 87 kmMarin County 94 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 2.1 (md)
Depth
-0.0 km below the surface
Felt
no reports yet
Nearest
Solano County, 27 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3226 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 37 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 410,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 290,000× the energy of this one
  3. Around the size people start to feel M 3.0 26× the energy of this one
  4. This earthquake M 2.1 about 37 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 38.1380, -121.6757. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Solano County, CA 27 km (17 mi) ESE of here earthquakes near Solano County
Contra Costa County, CA 34 km (21 mi) NE of here earthquakes near Contra Costa County
San Joaquin County, CA 42 km (26 mi) WNW of here earthquakes near San Joaquin County
Sacramento County, CA 45 km (28 mi) SW of here earthquakes near Sacramento County
Alameda County, CA 58 km (36 mi) NNE of here earthquakes near Alameda County
Yolo County, CA 63 km (39 mi) SSE of here earthquakes near Yolo 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. 1.6 1km WNW of Diablo, CA
  2. 1.9 2km WSW of Diablo, CA
  3. 2.8 2km WSW of Diablo, CA
  4. 2.0 2km WSW of Diablo, CA
  5. 1.7 2km W of Diablo, CA
  6. 2.1 2km WSW of Diablo, CA
  7. 1.7 2km WSW of Diablo, CA
  8. 2.6 2km W of Diablo, CA
  9. 2.1 2km W of Diablo, CA
  10. 1.8 2km W of Diablo, CA
  11. 2.3 2km WSW of Diablo, CA
  12. 1.5 2km WNW of Diablo, CA
  13. 1.6 1km W of Diablo, CA
  14. 1.5 1km WSW of Diablo, CA
  15. 1.7 1km WSW of Diablo, 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.