QuakeIndex

Earthquake · reviewed by a seismologist

M 1.9md

Earthquake near Fairfield, CA

No earthquake was likely felt in Fairfield in the 24 hours to 4:21 am PST (12:21 UTC). The last one was M 2.4, 18 km (11 mi) W, at 10:47 am PDT on 6 October 2026, estimated intensity II (weak) in town; 1 felt report to USGS. Every earthquake near Fairfield

This page: a magnitude 1.9 earthquake was recorded 16 km (10 mi) southeast of Fairfield, CA, at 4:14 am PDT on 2 June 2025 (11:14 UTC), 20 km deep.

USGS: 14 km SE of Suisun City, CA

63 km (39 mi) NE of San Francisco, CA · 16 km (10 mi) SE of Fairfield, CA

4:14 am PDT, Jun 2, 2025 · · 20 km deep · released about 24 lb of TNT

10 km30 km60 km120 km N Solano County 12 kmContra Costa County 28 kmNapa County 53 kmYolo County 57 kmSacramento County 57 kmAlameda County 58 kmSan Joaquin County 60 kmMarin County 76 kmSan Mateo County 94 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
4:14 am PDT on 2 June 2025 ()
Where
16 km (10 mi) southeast of Fairfield, CA · earthquakes near Fairfield
Magnitude
M 1.9 (md)
Depth
20 km below the surface
Felt
no reports yet
Nearest
Solano County, 12 km NNW
Nearest mapped fault
Great Valley thrust fault system, 14 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 524 days ago

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

At this magnitude and depth it was probably too small to be felt, even directly above it. In Fairfield, 16 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.

Earthquakes near other towns within 30 km: Suisun, Pittsburg, Bay Point, Rio Vista, Antioch, Vacaville.

How big was it?

This earthquake released about 24 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 640,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 450,000× the energy of this one
  3. Around the size people start to feel M 3.0 40× the energy of this one
  4. This earthquake M 1.9 about 24 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 4.5 on 2019-10-15 — about 6,200 times the energy of this one.

Before 2016, the USGS record lists 5 earthquakes of M5 or more within 50 km:

  1. 6.0 The 2014 South Napa, California Earthquake · 37 km W of this epicentre
  2. 5.8 The 1980 Livermore, California Earthquake · 38 km SSE of this epicentre
  3. 5.4 South of Elmira, California · 15 km N of this epicentre
  4. 5.4 9 km NE of Livermore, California · 49 km SSE of this epicentre
  5. 5.1 11 km E of Blackhawk, California · 41 km SSE 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 38.1682, -121.8923. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Solano County, CA 12 km (7 mi) NNW earthquakes near Solano County
Contra Costa County, CA 28 km (17 mi) S earthquakes near Contra Costa County
Napa County, CA 53 km (33 mi) NW earthquakes near Napa County
Yolo County, CA 57 km (35 mi) N earthquakes near Yolo County
Sacramento County, CA 57 km (36 mi) ENE earthquakes near Sacramento County
Alameda County, CA 58 km (36 mi) S earthquakes near Alameda County

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

Aftershocks so far

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

  1. 1.7 3 km ESE of Berkeley, CA
  2. 2.9 3 km SE of Berkeley, CA
  3. 2.6 3 km SE of Berkeley, CA
  4. 2.1 3 km ESE of Berkeley, CA
  5. 4.3 2 km ESE of Berkeley, CA
  6. 1.6 10 km ENE of Blackhawk, CA
  7. 1.6 9 km W of Brentwood, CA
  8. 1.6 2 km ENE of Oakland, CA
  9. 1.9 3 km SW of Clayton, CA
  10. 1.9 8 km ESE of Clayton, CA
  11. 3.3 8 km E of Clayton, CA
  12. 2.3 6 km SSW of Yountville, CA
  13. 1.6 7 km ENE of Vallejo, CA
  14. 1.6 4 km ESE of Vallejo, CA
  15. 2.0 2 km ENE of Berkeley, 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.