QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1ml

2km ENE of San Leandro, CA

· 4.3 km deep · released about 1,300 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Alameda County 22 kmContra Costa County 27 kmSan Mateo County 41 kmSolano County 62 kmMarin County 65 kmSanta Clara County 69 kmSan Francisco County 79 kmSan Joaquin County 79 kmSanta Cruz 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 3.1 (ml)
Depth
4.3 km below the surface
Felt
1429 reports · strongest reported intensity IV
Nearest
Alameda County, 22 km ESE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1433 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 1429 people have reported feeling it to USGS.

How big was it?

This earthquake released about 1,300 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 260,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 12,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 8,200× the energy of this one
  4. This earthquake M 3.1 about 1,300 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.4× 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 37.7282, -122.1357. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Alameda County, CA 22 km (13 mi) WNW of here earthquakes near Alameda County
Contra Costa County, CA 27 km (17 mi) SW of here earthquakes near Contra Costa County
San Mateo County, CA 41 km (25 mi) NNE of here earthquakes near San Mateo County
Solano County, CA 62 km (39 mi) SSW of here earthquakes near Solano County
Marin County, CA 65 km (40 mi) ESE of here earthquakes near Marin County
Santa Clara County, CA 69 km (43 mi) NW of here earthquakes near Santa Clara County

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

Aftershocks so far

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

  1. 2.3 10km SW of Brentwood, CA
  2. 1.6 10km ENE of Blackhawk, CA
  3. 1.8 3km S of Pittsburg, CA
  4. 1.9 5km ESE of Moraga, CA
  5. 2.7 4km S of Pittsburg, CA
  6. 1.9 6km SW of Clayton, CA
  7. 1.6 4km SW of San Ramon, CA
  8. 1.6 4km SW of San Ramon, CA
  9. 1.6 2km E of Pleasant Hill, CA
  10. 1.7 5km E of Vallejo, CA
  11. 1.7 10km ENE of Milpitas, CA
  12. 1.6 5km E of Fremont, CA
  13. 1.7 10km ESE of Clayton, CA
  14. 1.6 5km E of Vallejo, CA
  15. 1.6 7km S of Muir Beach, 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 110 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.