QuakeIndex

Earthquake · reviewed by a seismologist

M 1.5md

22km WSW of Patterson, CA

· 5.0 km deep · released about 5.4 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Santa Clara County 34 kmStanislaus County 37 kmMerced County 58 kmAlameda County 59 kmSan Joaquin County 64 kmSanta Cruz County 71 kmContra Costa County 82 kmSan Benito County 87 kmSan Mateo County 91 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 1.5 (md)
Depth
5.0 km below the surface
Felt
no reports yet
Nearest
Santa Clara County, 34 km WSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2187 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 5.4 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,800,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 2,000,000× the energy of this one
  3. Around the size people start to feel M 3.0 180× the energy of this one
  4. This earthquake M 1.5 about 5.4 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 37.3645, -121.3452. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Santa Clara County, CA 34 km (21 mi) ENE of here earthquakes near Santa Clara County
Stanislaus County, CA 37 km (23 mi) SW of here earthquakes near Stanislaus County
Merced County, CA 58 km (36 mi) WNW of here earthquakes near Merced County
Alameda County, CA 59 km (37 mi) ESE of here earthquakes near Alameda County
San Joaquin County, CA 64 km (40 mi) S of here earthquakes near San Joaquin County
Santa Cruz County, CA 71 km (44 mi) NE 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

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

  1. 1.8 9km ENE of Milpitas, CA
  2. 1.8 10km ESE of Livermore, CA
  3. 2.1 9km ENE of Milpitas, CA
  4. 2.0 14km SE of Livermore, CA
  5. 2.6 16km E of Seven Trees, CA
  6. 1.5 8km ENE of Alum Rock, CA
  7. 1.7 10km NNE of San Martin, CA
  8. 1.6 9km NE of Milpitas, CA
  9. 2.3 6km SSW of Gilroy, CA
  10. 3.5 10km ENE of Morgan Hill, CA
  11. 3.7 10km ENE of Morgan Hill, CA
  12. 1.6 8km ENE of Alum Rock, CA
  13. 2.2 11km NE of Milpitas, CA
  14. 1.5 10km SSE of Sunol, CA
  15. 1.8 6km WSW of Gilroy, 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 7,700 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.