QuakeIndex

Earthquake · reviewed by a seismologist

M 2.6md

1km ENE of Union City, CA

· 4.6 km deep · released about 210 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Alameda County 10 kmContra Costa County 36 kmSan Mateo County 38 kmSanta Clara County 50 kmSanta Cruz County 65 kmSan Joaquin County 74 kmSolano County 74 kmMarin County 82 kmStanislaus County 88 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 2.6 (md)
Depth
4.6 km below the surface
Felt
326 reports · strongest reported intensity IV
Nearest
Alameda County, 10 km ENE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1474 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 326 people have reported feeling it to USGS.

How big was it?

This earthquake released about 210 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 72,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 51,000× the energy of this one
  3. Around the size people start to feel M 3.0 4.6× the energy of this one
  4. This earthquake M 2.6 about 210 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 37.6002, -122.0043. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Alameda County, CA 10 km (6 mi) WSW of here earthquakes near Alameda County
Contra Costa County, CA 36 km (22 mi) S of here earthquakes near Contra Costa County
San Mateo County, CA 38 km (24 mi) ENE of here earthquakes near San Mateo County
Santa Clara County, CA 50 km (31 mi) NNW of here earthquakes near Santa Clara County
Santa Cruz County, CA 65 km (41 mi) N of here earthquakes near Santa Cruz County
San Joaquin County, CA 74 km (46 mi) WSW of here earthquakes near San Joaquin County

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

Aftershocks so far

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

  1. 1.6 5km NW of Dublin, CA
  2. 2.1 6km WNW of Dublin, CA
  3. 2.2 5km WNW of Dublin, CA
  4. 2.0 6km WNW of Dublin, CA
  5. 2.2 5km NW of Dublin, CA
  6. 1.6 5km NW of Dublin, CA
  7. 1.9 6km SW of Clayton, CA
  8. 1.7 2km ESE of Berkeley, CA
  9. 1.8 2km ESE of Berkeley, CA
  10. 1.6 16km NE of Alum Rock, CA
  11. 1.5 4km NW of Dublin, CA
  12. 1.6 1km ENE of Alameda, CA
  13. 1.5 5km WSW of Lexington Hills, CA
  14. 1.9 1km N of East Richmond Heights, CA
  15. 1.6 2km W of Concord, 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 710 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.