QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1ml

Earthquake near San Jose, CA

No earthquake was likely felt in San Jose in the 24 hours to 1:34 pm PST (21:34 UTC). The last one was M 2.6, 19 km (12 mi) E, at 12:38 pm PDT on 27 October 2026, estimated intensity II (weak) in town; 8 felt reports to USGS. Every earthquake near San Jose

This page: a magnitude 3.1 earthquake was recorded 22 km (14 mi) east-southeast of San Jose, CA, at 12:34 am PDT on 26 April 2023 (07:34 UTC), 6.3 km deep. 231 people have reported feeling it to USGS.

USGS: 16km E of Seven Trees, CA

14 km (9 mi) E of San Jose, CA

12:34 am PDT, Apr 26, 2023 · · 6.3 km deep · released about 1,300 lb of TNT

10 km30 km60 km120 km N Santa Clara County 8 kmSanta Cruz County 44 kmAlameda County 46 kmSan Mateo County 65 kmStanislaus County 65 kmContra Costa County 75 kmSan Joaquin County 80 kmMerced County 83 kmSan Benito 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
12:34 am PDT on 26 April 2023 ()
Where
22 km (14 mi) east-southeast of San Jose, CA · earthquakes near San Jose
Magnitude
M 3.1 (ml)
Depth
6.3 km below the surface
Felt
231 reports · strongest reported intensity IV
Nearest
Santa Clara County, 8 km SSW
Nearest mapped fault
Calaveras fault, under 1 km from its surface trace — near is not the same as on
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1200 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

At this magnitude and depth, people at rest would likely notice it out to about 41 km (25 mi) from the epicentre. In San Jose, 22 km away, the estimate is intensity II (weak). Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.

Likely felt in: Morgan Hill 17 km, intensity III · San Jose 22 km, intensity II · Campbell 26 km, intensity II · Milpitas 27 km, intensity II · Santa Clara 27 km, intensity II · Los Gatos 29 km, intensity II · Gilroy 32 km, intensity II · Saratoga 32 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 1,300 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 6.7 250,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 11,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 7,900× the energy of this one
  4. This earthquake M 3.1 about 1,300 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.4× 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.

For this area

The largest earthquake within 50 km since 2016 was M 5.1 on 2022-10-25 — about 870 times the energy of this one.

Before 2016, the USGS record lists 24 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.9 The 1989 Loma Prieta, California Earthquake · 34 km SW of this epicentre
  2. 6.5 Near Morgan Hill, California · 20 km S of this epicentre
  3. 6.2 Near San Jose, California · 13 km W of this epicentre
  4. 6.2 The 1984 Morgan Hill, California Earthquake · 3 km NW of this epicentre
  5. 6.1 Near San Jose, California · 16 km SW of this epicentre

Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.

Where

Epicentre 37.2868, -121.6577. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Santa Clara County, CA 8 km (5 mi) SSW earthquakes near Santa Clara County
Santa Cruz County, CA 44 km (27 mi) SW earthquakes near Santa Cruz County
Alameda County, CA 46 km (29 mi) NNW earthquakes near Alameda County
San Mateo County, CA 65 km (40 mi) WNW earthquakes near San Mateo County
Stanislaus County, CA 65 km (41 mi) ENE earthquakes near Stanislaus County
Contra Costa County, CA 75 km (47 mi) NNW earthquakes near Contra Costa County

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

Aftershocks so far

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

  1. 1.6 5 km NNW of Aromas, CA
  2. 1.9 24 km NE of Alum Rock, CA
  3. 1.6 6km SW of Gilroy, CA
  4. 1.8 11km NNW of Hollister, CA
  5. 1.5 3km SSW of Cupertino, CA
  6. 2.3 6km N of Hollister, CA
  7. 3.0 8km NE of Gilroy, CA
  8. 1.9 8km NE of Gilroy, CA
  9. 2.0 7km SSE of Portola Valley, CA
  10. 1.6 7km WSW of Gilroy, CA
  11. 1.8 6km E of Milpitas, CA
  12. 2.4 8km NE of Gilroy, CA
  13. 1.6 19km SW of Gustine, CA
  14. 1.6 10km NE of Morgan Hill, CA
  15. 2.1 19km SW of Gustine, 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.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.