QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

Earthquake near Cupertino, CA

No earthquake was likely felt in Cupertino in the 24 hours to 10:23 pm PST (06:23 UTC). The last one was M 2.0, 4 km (3 mi) WSW, at 9:23 am PST on 10 November 2026, estimated intensity II (weak) in town; 4 felt reports to USGS. Every earthquake near Cupertino

This page: a magnitude 1.8 earthquake was recorded 3 km (2 mi) south-southwest of Cupertino, CA, at 11:11 pm PST on 12 January 2023 (07:11 UTC), 7.3 km deep.

USGS: 4km SSW of Cupertino, CA

20 km (12 mi) W of San Jose, CA · in Cupertino, CA

11:11 pm PST, Jan 12, 2023 · · 7.3 km deep · released about 16 lb of TNT

10 km30 km60 km120 km N Santa Cruz County 31 kmSanta Clara County 32 kmSan Mateo County 32 kmAlameda County 41 kmContra Costa County 70 kmStanislaus County 96 kmSan Joaquin County 98 kmSan Francisco County 100 kmMarin County 105 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
11:11 pm PST on 12 January 2023 ()
Where
3 km (2 mi) south-southwest of Cupertino, CA · earthquakes near Cupertino
Magnitude
M 1.8 (md)
Depth
7.3 km below the surface
Felt
no reports yet
Nearest
Santa Cruz County, 31 km S
Nearest mapped fault
Monte Vista-Shannon 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 1394 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth, people at rest would likely notice it out to about 12 km (7 mi) from the epicentre. In Cupertino, 3 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: Cupertino 3 km, intensity II · Saratoga 4 km, intensity II · Campbell 8 km, intensity II · Sunnyvale 9 km, intensity II · Los Gatos 9 km, intensity II · Santa Clara 10 km, intensity II · Mountain View 11 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 16 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 930,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 660,000× the energy of this one
  3. Around the size people start to feel M 3.0 59× the energy of this one
  4. This earthquake M 1.8 about 16 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.

For this area

The largest earthquake within 50 km since 2016 was M 5.1 on 2022-10-25 — about 72,000 times the energy of this one.

Before 2016, the USGS record lists 21 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.9 The 1989 Loma Prieta, California Earthquake · 32 km SSE of this epicentre
  2. 6.5 Near Morgan Hill, California · 41 km ESE of this epicentre
  3. 6.3 16 km SW of Davenport, California · 49 km SSW of this epicentre
  4. 6.2 Near San Jose, California · 21 km E of this epicentre
  5. 6.2 The 1984 Morgan Hill, California Earthquake · 32 km E 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 37.2923, -122.0410. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Santa Cruz County, CA 31 km (19 mi) S earthquakes near Santa Cruz County
Santa Clara County, CA 32 km (20 mi) ESE earthquakes near Santa Clara County
San Mateo County, CA 32 km (20 mi) WNW earthquakes near San Mateo County
Alameda County, CA 41 km (26 mi) NNE earthquakes near Alameda County
Contra Costa County, CA 70 km (44 mi) N earthquakes near Contra Costa County
Stanislaus County, CA 96 km (60 mi) ENE earthquakes near Stanislaus County

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

Aftershocks so far

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

  1. 3.0 16km E of Seven Trees, CA
  2. 1.6 11km N of Morgan Hill, CA
  3. 1.5 5km NE of San Martin, CA
  4. 2.0 18km SSE of Livermore, CA
  5. 1.6 13km SSE of Livermore, CA
  6. 2.9 19km SSE of Livermore, CA
  7. 1.6 1km SSE of Portola Valley, CA
  8. 2.4 12km NNE of Alum Rock, CA
  9. 2.1 15km E of Seven Trees, CA
  10. 1.9 9km NE of Corralitos, CA
  11. 2.2 13km NE of Milpitas, CA
  12. 1.5 1km WNW of Corralitos, CA
  13. 1.8 16km E of Seven Trees, CA
  14. 2.4 14km N of Morgan Hill, CA
  15. 1.6 12km ENE of Milpitas, 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.