QuakeIndex

Earthquake · reviewed by a seismologist

M 2.4md

4 km ESE of Clayton, California

· 12 km deep · released about 130 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Contra Costa County 6 kmAlameda County 31 kmSolano County 38 kmSan Joaquin County 54 kmSan Mateo County 71 kmNapa County 75 kmSacramento County 75 kmMarin County 76 kmSanta Clara 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 2.4 (md)
Depth
12 km below the surface
Felt
4 reports · strongest reported intensity III
Nearest
Contra Costa County, 6 km W
Nearest mapped fault
Greenville fault, 1 km from its surface trace — near is not the same as on
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3458 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 4 people have reported feeling it to USGS.

How big was it?

This earthquake released about 130 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.4 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 110,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 80,000× the energy of this one
  3. Around the size people start to feel M 3.0 7.2× the energy of this one
  4. This earthquake M 2.4 about 130 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 37.9270, -121.8887. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Contra Costa County, CA 6 km (3 mi) E of here earthquakes near Contra Costa County
Alameda County, CA 31 km (19 mi) N of here earthquakes near Alameda County
Solano County, CA 38 km (24 mi) S of here earthquakes near Solano County
San Joaquin County, CA 54 km (34 mi) W of here earthquakes near San Joaquin County
San Mateo County, CA 71 km (44 mi) NE of here earthquakes near San Mateo County
Napa County, CA 75 km (47 mi) SSE of here earthquakes near Napa County

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

Aftershocks so far

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

  1. 2.2 0 km ESE of North Gate, California
  2. 2.0 4 km NNW of Orinda, California
  3. 1.6 4 km SW of Danville, California
  4. 2.1 2 km SSW of San Ramon, California
  5. 2.2 1 km SSW of San Ramon, California
  6. 2.0 1 km W of Danville, California
  7. 1.5 2 km E of Berkeley, California
  8. 1.6 2 km SW of American Canyon, California
  9. 2.2 Northern California
  10. 1.6 11 km SE of Sunol, CA
  11. 2.2 5 km S of Livermore, California
  12. 1.7 3 km W of Byron, California
  13. 1.6 4 km SSW of Byron, California
  14. 1.7 1 km ESE of Pacheco, California
  15. 1.7 2 km NE of San Ramon, 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.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.