QuakeIndex

Earthquake · reviewed by a seismologist

M 2.0md

24km NE of Alum Rock, CA

· 7.1 km deep · released about 31 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Alameda County 30 kmSanta Clara County 32 kmContra Costa County 55 kmStanislaus County 55 kmSan Joaquin County 57 kmSanta Cruz County 64 kmSan Mateo County 67 kmMerced County 87 kmSolano County 89 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 2.0 (md)
Depth
7.1 km below the surface
Felt
no reports yet
Nearest
Alameda County, 30 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1586 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

How big was it?

This earthquake released about 31 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.0 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 480,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 340,000× the energy of this one
  3. Around the size people start to feel M 3.0 31× the energy of this one
  4. This earthquake M 2.0 about 31 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 37.5028, -121.6230. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Alameda County, CA 30 km (19 mi) ESE of here earthquakes near Alameda County
Santa Clara County, CA 32 km (20 mi) N of here earthquakes near Santa Clara County
Contra Costa County, CA 55 km (34 mi) SSE of here earthquakes near Contra Costa County
Stanislaus County, CA 55 km (34 mi) W of here earthquakes near Stanislaus County
San Joaquin County, CA 57 km (35 mi) SSW of here earthquakes near San Joaquin County
Santa Cruz County, CA 64 km (40 mi) NNE of here earthquakes near Santa Cruz 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. 1.6 11km NE of Milpitas, CA
  2. 2.2 10km SE of Sunol, CA
  3. 2.1 10km ESE of Fremont, CA
  4. 1.8 24km SSE of Livermore, CA
  5. 1.9 8km WSW of Mountain House, CA
  6. 1.8 2km WNW of Los Altos Hills, CA
  7. 3.4 24km NE of Alum Rock, CA
  8. 2.0 8km NE of San Martin, CA
  9. 1.9 10km E of Alum Rock, CA
  10. 2.7 9km ENE of San Martin, CA
  11. 1.6 15km E of Seven Trees, CA
  12. 1.9 3km WSW of Cupertino, CA
  13. 1.7 28km ENE of Alum Rock, CA
  14. 1.8 9km ENE of Morgan Hill, CA
  15. 3.4 14km 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 4.3 on 2019-07-16 — it released about 2,800 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.