QuakeIndex

Earthquake · automatic estimate, may change

M 2.0md

Earthquake near Fairfield, CA

No earthquake was likely felt in Fairfield in the 24 hours to 11:02 pm PST (07:02 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 2.0 earthquake was recorded 10 km (6 mi) east of Fairfield, CA, at 3:06 pm PDT on 28 October 2025 (22:06 UTC), less than 1 km deep. The magnitude and location are an automatic first estimate and may change.

USGS: 8 km E of Suisun City, CA

9 km (6 mi) ESE of Fairfield, CA

3:06 pm PDT, Oct 28, 2025 · · 0.5 km deep · released about 31 lb of TNT

10 km30 km60 km120 km N Solano County 3 kmContra Costa County 36 kmNapa County 45 kmYolo County 49 kmSacramento County 56 kmAlameda County 66 kmSan Joaquin County 67 kmMarin County 75 kmSutter County 90 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
3:06 pm PDT on 28 October 2025 ()
Where
10 km (6 mi) east of Fairfield, CA · earthquakes near Fairfield
Magnitude
M 2.0 (md)
Depth
0.5 km below the surface
Felt
no reports yet
Nearest
Solano County, 3 km NNW
Nearest mapped fault
Great Valley thrust fault system, 5 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 379 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 16 km (10 mi) from the epicentre. In Fairfield, 10 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: Fairfield 10 km, intensity II · Suisun 10 km, intensity II · Vacaville 14 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 31 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.0 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 480,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 340,000× the energy of this one
  3. Around the size people start to feel M 3.0 31× the energy of this one
  4. This earthquake M 2.0 about 31 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 4,700 times the energy of this one.

Before 2016, the USGS record lists 4 earthquakes of M5 or more within 50 km:

  1. 6.0 The 2014 South Napa, California Earthquake · 34 km W of this epicentre
  2. 5.8 The 1980 Livermore, California Earthquake · 47 km SSE of this epicentre
  3. 5.4 South of Elmira, California · 7 km NNE of this epicentre
  4. 5.1 11 km E of Blackhawk, California · 50 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 38.2435, -121.9295. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Solano County, CA 3 km (2 mi) NNW earthquakes near Solano County
Contra Costa County, CA 36 km (22 mi) S earthquakes near Contra Costa County
Napa County, CA 45 km (28 mi) NW earthquakes near Napa County
Yolo County, CA 49 km (30 mi) N earthquakes near Yolo County
Sacramento County, CA 56 km (35 mi) ENE earthquakes near Sacramento County
Alameda County, CA 66 km (41 mi) S earthquakes near Alameda County

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

Aftershocks so far

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

  1. 2.3 5 km NNW of Pittsburg, CA
  2. 1.6 2 km ESE of Pacheco, CA
  3. 1.9 2 km E of Danville, CA
  4. 1.8 6 km NE of Alamo, CA
  5. 2.5 10 km ESE of Black Point-Green Point, CA
  6. 1.7 6 km ENE of Vallejo, CA
  7. 2.0 6 km SE of Napa, CA
  8. 1.8 6 km ENE of Vallejo, CA
  9. 2.2 9 km N of Bay Point, CA
  10. 2.4 3 km S of Walnut Creek, CA
  11. 1.9 3 km NNW of Pittsburg, CA
  12. 1.6 1 km N of Pleasant Hill, CA
  13. 1.6 9 km SSW of Brentwood, CA
  14. 1.6 12 km E of Yountville, CA
  15. 1.8 4 km SSW of Yountville, 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.