QuakeIndex

Earthquake · reviewed by a seismologist

M 2.4md

0km W of Pleasant Hill, CA

· 11 km deep · released about 120 lb of TNT

10 km30 km60 km120 km N Contra Costa County 11 kmAlameda County 36 kmSolano County 37 kmMarin County 61 kmSan Mateo County 65 kmNapa County 66 kmSan Joaquin County 70 kmYolo County 83 kmSacramento County 84 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
11 km below the surface
Felt
54 reports · strongest reported intensity IV
Nearest
Contra Costa County, 11 km ESE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1985 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 54 people have reported feeling it to USGS.

How big was it?

This earthquake released about 120 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 5.8 120,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 86,000× the energy of this one
  3. Around the size people start to feel M 3.0 7.7× the energy of this one
  4. This earthquake M 2.4 about 120 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 37.9487, -122.0665. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Contra Costa County, CA 11 km (7 mi) WNW of here earthquakes near Contra Costa County
Alameda County, CA 36 km (22 mi) NNW of here earthquakes near Alameda County
Solano County, CA 37 km (23 mi) SSW of here earthquakes near Solano County
Marin County, CA 61 km (38 mi) E of here earthquakes near Marin County
San Mateo County, CA 65 km (40 mi) NNE of here earthquakes near San Mateo County
Napa County, CA 66 km (41 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

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

  1. 1.6 8km S of Muir Beach, CA
  2. 1.7 3km NNW of Byron, CA
  3. 1.6 3km NNW of Piedmont, CA
  4. 2.1 2km ENE of Berkeley, CA
  5. 1.7 3km WNW of Castro Valley, CA
  6. 1.9 1km NNW of Crockett, CA
  7. 2.7 6km SSW of San Ramon, CA
  8. 3.9 3km N of San Lorenzo, CA
  9. 1.7 5km E of Vallejo, CA
  10. 1.8 2km ESE of Berkeley, CA
  11. 1.8 6km E of Fremont, CA
  12. 2.6 2km ENE of Hayward, CA
  13. 1.6 3km SSW of Clayton, CA
  14. 1.7 7km SSW of Muir Beach, CA
  15. 1.6 1km W of Alamo, 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 1,200 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.