QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1mw

11km ENE of San Martin, CA

· -0.3 km deep · released about 1,400 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Santa Clara County 22 kmSanta Cruz County 47 kmSan Benito County 66 kmStanislaus County 67 kmMerced County 69 kmAlameda County 71 kmSan Mateo County 85 kmSan Joaquin County 94 kmMonterey County 97 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 3.1 (mw)
Depth
-0.3 km below the surface
Felt
32 reports · strongest reported intensity III
Nearest
Santa Clara County, 22 km NW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2656 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 32 people have reported feeling it to USGS.

How big was it?

This earthquake released about 1,400 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 230,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 10,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 7,400× the energy of this one
  4. This earthquake M 3.1 about 1,400 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.5× more

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 37.1043, -121.4917. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Santa Clara County, CA 22 km (14 mi) SE of here earthquakes near Santa Clara County
Santa Cruz County, CA 47 km (29 mi) ENE of here earthquakes near Santa Cruz County
San Benito County, CA 66 km (41 mi) NNW of here earthquakes near San Benito County
Stanislaus County, CA 67 km (42 mi) SW of here earthquakes near Stanislaus County
Merced County, CA 69 km (43 mi) W of here earthquakes near Merced County
Alameda County, CA 71 km (44 mi) SSE of here earthquakes near Alameda County

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

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

  1. 1.7 2km NNW of Aromas, CA
  2. 1.5 16km N of Morgan Hill, CA
  3. 2.4 8km NE of Alum Rock, CA
  4. 1.6 16km N of Morgan Hill, CA
  5. 1.6 6km SW of Gilroy, CA
  6. 1.5 13km NNE of Morgan Hill, CA
  7. 2.5 8km ENE of Alum Rock, CA
  8. 2.2 8km ENE of Alum Rock, CA
  9. 2.0 8km ENE of Alum Rock, CA
  10. 3.0 3km ESE of Aromas, CA
  11. 1.8 1km NE of Tres Pinos, CA
  12. 1.5 18km WSW of Westley, CA
  13. 2.6 9km SW of Ridgemark, CA
  14. 2.7 8km SW of Ridgemark, CA
  15. 1.6 3km E of Aromas, 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 4.2 on 2016-07-19 — it released about 45 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.