QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

12 km W of Rio Vista, CA

· 29 km deep · released about 41 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Solano County 17 kmContra Costa County 27 kmSan Joaquin County 54 kmSacramento County 54 kmAlameda County 56 kmNapa County 59 kmYolo County 60 kmMarin County 81 kmSan Mateo 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
29 km below the surface
Felt
no reports yet
Nearest
Solano County, 17 km NW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 530 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 41 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 5.8 370,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 260,000× the energy of this one
  3. Around the size people start to feel M 3.0 23× the energy of this one
  4. This earthquake M 2.1 about 41 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 38.1457, -121.8287. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Solano County, CA 17 km (10 mi) SE of here earthquakes near Solano County
Contra Costa County, CA 27 km (17 mi) NNE of here earthquakes near Contra Costa County
San Joaquin County, CA 54 km (34 mi) WNW of here earthquakes near San Joaquin County
Sacramento County, CA 54 km (34 mi) SW of here earthquakes near Sacramento County
Alameda County, CA 56 km (35 mi) N of here earthquakes near Alameda County
Napa County, CA 59 km (37 mi) SE of here earthquakes near Napa 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. 1.7 3 km NNE of Dublin, CA
  2. 1.8 7 km E of Vallejo, CA
  3. 1.5 3 km SW of Clayton, CA
  4. 1.9 3 km ESE of Walnut Creek, CA
  5. 1.9 6 km SE of Moraga, CA
  6. 2.2 13 km SE of Suisun City, CA
  7. 2.7 6 km ESE of Clayton, CA
  8. 1.6 5 km E of Vallejo, CA
  9. 2.0 3 km WSW of Country Club, CA
  10. 2.1 4 km SE of Rodeo, CA
  11. 1.6 3 km SE of Rodeo, CA
  12. 3.2 2 km NW of Pinole, CA
  13. 1.5 3 km WSW of San Ramon, CA
  14. 1.7 2 km SSE of Danville, CA
  15. 1.8 1 km WSW of Concord, 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 4.5 on 2019-10-15 — it released about 3,600 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.