QuakeIndex

Earthquake · reviewed by a seismologist

M 2.3md

10km NW of Westley, CA

· 14 km deep · released about 85 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Stanislaus County 25 kmSan Joaquin County 35 kmAlameda County 56 kmSanta Clara County 58 kmMerced County 68 kmContra Costa County 68 kmCalaveras County 90 kmSacramento County 93 kmSolano 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 2.3 (md)
Depth
14 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Stanislaus County, 25 km ESE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1434 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 1 person has reported feeling it to USGS.

How big was it?

This earthquake released about 85 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.3 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 180,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 130,000× the energy of this one
  3. Around the size people start to feel M 3.0 11× the energy of this one
  4. This earthquake M 2.3 about 85 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 37.6198, -121.2737. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Stanislaus County, CA 25 km (15 mi) WNW of here earthquakes near Stanislaus County
San Joaquin County, CA 35 km (22 mi) S of here earthquakes near San Joaquin County
Alameda County, CA 56 km (35 mi) E of here earthquakes near Alameda County
Santa Clara County, CA 58 km (36 mi) NE of here earthquakes near Santa Clara County
Merced County, CA 68 km (42 mi) NW of here earthquakes near Merced County
Contra Costa County, CA 68 km (42 mi) ESE of here earthquakes near Contra Costa 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. 1.6 12km ENE of Milpitas, CA
  2. 1.6 12km ENE of Milpitas, CA
  3. 1.6 12km ENE of Milpitas, CA
  4. 1.8 15km E of Seven Trees, CA
  5. 2.4 16km E of Seven Trees, CA
  6. 1.5 8km SSW of Livermore, CA
  7. 2.5 8km NNE of Alum Rock, CA
  8. 1.7 10km E of Alum Rock, CA
  9. 1.6 20km NE of Alum Rock, CA
  10. 1.5 19km WSW of Gustine, CA
  11. 1.5 15km E of Seven Trees, CA
  12. 2.0 15km E of Seven Trees, CA
  13. 1.6 18km WSW of Westley, CA
  14. 1.6 3km NW of Byron, CA
  15. 2.1 12km 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 1,000 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.