QuakeIndex

Earthquake · automatic estimate, may change

M 1.6md

Earthquake near Milpitas, CA

Yes. A magnitude 1.6 earthquake was recorded 9 km (5 mi) NNE of Milpitas, CA, at 5:49 am PDT on 4 October 2026 (12:49 UTC), 5.7 km deep. The magnitude and location are an automatic first estimate and may change.

This was on 4 October 2026. The latest near Milpitas: M 2.5 on 19 September 2026.

USGS: 9 km NNE of Milpitas, CA

23 km (14 mi) N of San Jose, CA · 7 km (4 mi) E of Fremont, CA

5:49 am PDT, Oct 4, 2026 · · 5.7 km deep · released about 8.1 lb of TNT

10 km30 km60 km120 km N Alameda County 17 kmSanta Clara County 34 kmSan Mateo County 46 kmContra Costa County 48 kmSanta Cruz County 56 kmSan Joaquin County 71 kmStanislaus County 76 kmSolano County 86 kmMarin County 99 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
5:49 am PDT on 4 October 2026 ()
Where
9 km (5 mi) NNE of Milpitas, CA · earthquakes near Milpitas
Magnitude
M 1.6 (md)
Depth
5.7 km below the surface
Felt
no reports yet
Nearest
Alameda County, 17 km NNW
Nearest mapped fault
Hayward fault, 3 km from its surface trace — near is not the same as on
Status
Automatic — a machine’s first estimate, which may change

USGS · last changed by USGS · we first saw it 9 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 10 km (6 mi) from the epicentre. In Milpitas, 9 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: Milpitas 9 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 8.1 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,900,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,300,000× the energy of this one
  3. Around the size people start to feel M 3.0 120× the energy of this one
  4. This earthquake M 1.6 about 8.1 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 140,000 times the energy of this one.

Before 2016, the USGS record lists 16 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.5 Near Morgan Hill, California · 47 km SSE of this epicentre
  2. 6.2 Near San Jose, California · 23 km SSE of this epicentre
  3. 6.2 The 1984 Morgan Hill, California Earthquake · 26 km SE of this epicentre
  4. 6.1 Near San Jose, California · 34 km S of this epicentre
  5. 5.8 7 km NNW of Boulder Creek, California · 43 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 37.4983, -121.8597. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Alameda County, CA 17 km (11 mi) NNW earthquakes near Alameda County
Santa Clara County, CA 34 km (21 mi) SSE earthquakes near Santa Clara County
San Mateo County, CA 46 km (29 mi) WSW earthquakes near San Mateo County
Contra Costa County, CA 48 km (30 mi) N earthquakes near Contra Costa County
Santa Cruz County, CA 56 km (35 mi) SSW earthquakes near Santa Cruz County
San Joaquin County, CA 71 km (44 mi) NE earthquakes near San Joaquin County

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

Aftershocks so far

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

  1. 1.6 26 km WSW of Westley, CA
  2. 1.4 3 km NNE of San Leandro, CA
  3. 0.7 20 km E of Alum Rock, CA
  4. 1.9 1 km NE of Woodside, CA
  5. 2.3 4 km SSW of Lexington Hills, CA
  6. 0.9 14 km SSE of Livermore, CA
  7. 1.7 2 km SSE of Los Altos Hills, CA
  8. 2.2 8 km ENE of Morgan Hill, CA
  9. 1.6 6 km SW of Clayton, 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.