QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

17km ESE of Livermore, CA

· 2.0 km deep · released about 47 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Alameda County 27 kmSanta Clara County 43 kmContra Costa County 46 kmSan Joaquin County 47 kmStanislaus County 53 kmSan Mateo County 71 kmSanta Cruz County 75 kmSolano County 79 kmMerced County 90 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
2.0 km below the surface
Felt
3 reports · strongest reported intensity II
Nearest
Alameda County, 27 km W
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2747 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 47 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 5.8 320,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 230,000× the energy of this one
  3. Around the size people start to feel M 3.0 20× the energy of this one
  4. This earthquake M 2.1 about 47 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 37.6063, -121.6058. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Alameda County, CA 27 km (17 mi) E of here earthquakes near Alameda County
Santa Clara County, CA 43 km (27 mi) N of here earthquakes near Santa Clara County
Contra Costa County, CA 46 km (29 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
Stanislaus County, CA 53 km (33 mi) W of here earthquakes near Stanislaus County
San Mateo County, CA 71 km (44 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

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

  1. 1.8 3km S of Alamo, CA
  2. 2.1 8km E of Alum Rock, CA
  3. 1.6 22km NE of Alum Rock, CA
  4. 1.8 10km E of Alum Rock, CA
  5. 1.5 12km E of Blackhawk, CA
  6. 1.6 14km SSE of Livermore, CA
  7. 2.1 9km NNE of Alum Rock, CA
  8. 1.9 10km ENE of Morgan Hill, CA
  9. 1.5 9km NNE of Alum Rock, CA
  10. 1.6 8km SE of Seven Trees, CA
  11. 1.8 2km NE of San Leandro, CA
  12. 2.5 12km NNE of Morgan Hill, CA
  13. 2.3 12km NNE of Morgan Hill, CA
  14. 2.9 12km NNE of Morgan Hill, CA
  15. 2.0 3km E of Union City, 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 4.1 on 2017-10-10 — it released about 870 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.