QuakeIndex

Earthquake · reviewed by a seismologist

M 1.5md

21km SW of Patterson, CA

· 2.5 km deep · released about 5.7 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Stanislaus County 36 kmSanta Clara County 37 kmMerced County 53 kmAlameda County 65 kmSan Joaquin County 67 kmSanta Cruz County 72 kmSan Benito County 82 kmContra Costa County 87 kmSan Mateo County 95 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
2.5 km below the surface
Felt
no reports yet
Nearest
Stanislaus County, 36 km NE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2852 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 5.7 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 2,600,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,900,000× the energy of this one
  3. Around the size people start to feel M 3.0 170× the energy of this one
  4. This earthquake M 1.5 about 5.7 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 37.3328, -121.2977. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Stanislaus County, CA 36 km (23 mi) SW of here earthquakes near Stanislaus County
Santa Clara County, CA 37 km (23 mi) ENE of here earthquakes near Santa Clara County
Merced County, CA 53 km (33 mi) WNW of here earthquakes near Merced County
Alameda County, CA 65 km (40 mi) ESE of here earthquakes near Alameda County
San Joaquin County, CA 67 km (42 mi) S of here earthquakes near San Joaquin County
Santa Cruz County, CA 72 km (45 mi) ENE 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

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

  1. 2.6 12km ESE of Alum Rock, CA
  2. 1.6 12km ESE of Alum Rock, CA
  3. 2.1 8km E of Alum Rock, CA
  4. 1.6 22km NE of Alum Rock, CA
  5. 2.0 7km WSW of Gilroy, CA
  6. 2.0 11km ENE of San Martin, CA
  7. 2.7 11km ENE of San Martin, CA
  8. 1.8 10km E of Alum Rock, CA
  9. 1.7 23km NE of Hollister, CA
  10. 3.1 11km ENE of San Martin, CA
  11. 1.9 11km ENE of San Martin, CA
  12. 1.6 14km SSE of Livermore, CA
  13. 2.1 9km NNE of Alum Rock, CA
  14. 1.9 10km ENE of Morgan Hill, CA
  15. 1.7 7km 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 7,200 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.