QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

10km ESE of Livermore, CA

· 3.5 km deep · released about 41 lb of TNT

10 km30 km60 km120 km N Alameda County 22 kmContra Costa County 39 kmSan Joaquin County 47 kmSanta Clara County 48 kmStanislaus County 59 kmSan Mateo County 68 kmSolano County 73 kmSanta Cruz County 77 kmSacramento County 93 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 2.1 (md)
Depth
3.5 km below the surface
Felt
3 reports · strongest reported intensity III
Nearest
Alameda County, 22 km W
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2195 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 3 people have reported feeling it to USGS.

How big was it?

This earthquake released about 41 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 370,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 260,000× the energy of this one
  3. Around the size people start to feel M 3.0 23× the energy of this one
  4. This earthquake M 2.1 about 41 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 37.6520, -121.6640. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Alameda County, CA 22 km (14 mi) E of here earthquakes near Alameda County
Contra Costa County, CA 39 km (24 mi) SE of here earthquakes near Contra Costa County
San Joaquin County, CA 47 km (29 mi) SW of here earthquakes near San Joaquin County
Santa Clara County, CA 48 km (30 mi) N of here earthquakes near Santa Clara County
Stanislaus County, CA 59 km (37 mi) W of here earthquakes near Stanislaus County
San Mateo County, CA 68 km (42 mi) ENE 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

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

  1. 2.1 4km ESE of Hayward, CA
  2. 2.1 4km WNW of Dublin, CA
  3. 1.7 4km WNW of Dublin, CA
  4. 1.7 4km WNW of Dublin, CA
  5. 2.3 4km WNW of Dublin, CA
  6. 2.0 2km E of Pacheco, CA
  7. 1.8 2km N of Knightsen, CA
  8. 1.7 5km S of Blackhawk, CA
  9. 1.6 8km ENE of Alum Rock, CA
  10. 1.7 1km WSW of Pleasant Hill, CA
  11. 2.2 11km NE of Milpitas, CA
  12. 1.5 10km SSE of Sunol, CA
  13. 2.3 2km ESE of Pleasanton, CA
  14. 1.9 5km NE of Alum Rock, CA
  15. 1.5 13km ESE of Alum Rock, 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 3,600 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.