QuakeIndex

Earthquake · reviewed by a seismologist

M 2.3md

4km SSE of Vallejo, CA

· 9.6 km deep · released about 74 lb of TNT

10 km30 km60 km120 km N Contra Costa County 30 kmSolano County 32 kmMarin County 46 kmNapa County 48 kmAlameda County 56 kmYolo County 72 kmSan Mateo County 75 kmSonoma County 78 kmSan Francisco County 81 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 2.3 (md)
Depth
9.6 km below the surface
Felt
14 reports · strongest reported intensity IV
Nearest
Contra Costa County, 30 km SE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1513 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 14 people have reported feeling it to USGS.

How big was it?

This earthquake released about 74 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.3 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 200,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 140,000× the energy of this one
  3. Around the size people start to feel M 3.0 13× the energy of this one
  4. This earthquake M 2.3 about 74 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 38.0825, -122.2257. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Contra Costa County, CA 30 km (19 mi) NW of here earthquakes near Contra Costa County
Solano County, CA 32 km (20 mi) SW of here earthquakes near Solano County
Marin County, CA 46 km (28 mi) E of here earthquakes near Marin County
Napa County, CA 48 km (30 mi) S of here earthquakes near Napa County
Alameda County, CA 56 km (35 mi) NNW of here earthquakes near Alameda County
Yolo County, CA 72 km (45 mi) SSW of here earthquakes near Yolo 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. 1.6 5km E of Vallejo, CA
  2. 1.6 6km ESE of Penngrove, CA
  3. 1.5 12km E of Yountville, CA
  4. 2.2 6km ESE of Penngrove, CA
  5. 1.6 9km NNE of Benicia, CA
  6. 1.9 1km W of Martinez, CA
  7. 1.5 2km NE of San Ramon, CA
  8. 1.6 5km E of Blackhawk, CA
  9. 1.6 2km NNE of Pleasant Hill, CA
  10. 1.9 7km NW of Bay Point, CA
  11. 1.8 7km NW of Bay Point, CA
  12. 2.0 6km NW of Bay Point, CA
  13. 2.2 7km NW of Bay Point, CA
  14. 1.8 6km NNW of Bay Point, CA
  15. 1.9 5km NNW of Bay Point, 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 2,000 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.