QuakeIndex

Earthquake · reviewed by a seismologist

M 3.5mw

2km NW of Crockett, CA

· 8.8 km deep · released about 3 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Contra Costa County 29 kmSolano County 34 kmMarin County 45 kmNapa County 50 kmAlameda County 54 kmSan Mateo County 73 kmYolo County 74 kmSan Francisco County 80 kmSonoma County 80 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 3.5 (mw)
Depth
8.8 km below the surface
Felt
2124 reports · strongest reported intensity IV
Measured shaking
intensity IV (ShakeMap)
Nearest
Contra Costa County, 29 km ESE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2213 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 2124 people have reported feeling it to USGS.

How big was it?

This earthquake released about 3 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.5 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 57,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 2,500× the energy of this one
  3. Magna, Utah 2020 M 5.7 1,800× the energy of this one
  4. This earthquake M 3.5 about 3 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 6.2× more

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 38.0610, -122.2285. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Contra Costa County, CA 29 km (18 mi) WNW of here earthquakes near Contra Costa County
Solano County, CA 34 km (21 mi) SW of here earthquakes near Solano County
Marin County, CA 45 km (28 mi) E of here earthquakes near Marin County
Napa County, CA 50 km (31 mi) S of here earthquakes near Napa County
Alameda County, CA 54 km (33 mi) NNW of here earthquakes near Alameda County
San Mateo County, CA 73 km (45 mi) N of here earthquakes near San Mateo County

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

Aftershocks so far

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

  1. 2.8 3km NE of Oakland, CA
  2. 2.0 1km NNE of Pacheco, CA
  3. 1.5 3km ESE of Berkeley, CA
  4. 1.9 2km ENE of Berkeley, CA
  5. 2.0 12km NE of Napa, CA
  6. 2.0 10km ENE of Blackhawk, CA
  7. 1.9 10km ENE of Blackhawk, CA
  8. 2.2 10km ENE of Blackhawk, CA
  9. 1.8 8km W of Yountville, CA
  10. 3.7 6km SSW of Yountville, CA
  11. 2.1 1km N of Pacheco, CA
  12. 2.0 1km N of Pacheco, CA
  13. 1.9 4km WSW of Daly City, CA
  14. 1.6 2km NNW of Danville, CA
  15. 1.8 13km E of Yountville, 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 2018-01-04 — it released about 19 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.