QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6md

Earthquake near Fairfield, CA

No earthquake was likely felt in Fairfield in the 24 hours to 1:37 am PST (09:37 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 1.6 earthquake was recorded 6 km (4 mi) south of Fairfield, CA, at 3:16 am PDT on 21 September 2022 (10:16 UTC), less than 1 km deep.

USGS: 6km SSW of Suisun City, CA

8 km (5 mi) S of Fairfield, CA

3:16 am PDT, Sep 21, 2022 · · -0.1 km deep · released about 8.1 lb of TNT

10 km30 km60 km120 km N Solano County 12 kmContra Costa County 31 kmNapa County 43 kmYolo County 55 kmAlameda County 62 kmMarin County 64 kmSacramento County 66 kmSan Joaquin County 72 kmSonoma County 86 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
3:16 am PDT on 21 September 2022 ()
Where
6 km (4 mi) south of Fairfield, CA · earthquakes near Fairfield
Magnitude
M 1.6 (md)
Depth
-0.1 km below the surface
Felt
no reports yet
Nearest
Solano County, 12 km NE
Nearest mapped fault
Cordelia fault, 9 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 1513 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 11 km (7 mi) from the epicentre. In Fairfield, 6 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: Suisun 5 km, intensity II · Fairfield 6 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 4.5 on 2019-10-15 — about 18,000 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 · 25 km W of this epicentre
  2. 5.8 The 1980 Livermore, California Earthquake · 46 km SSE of this epicentre
  3. 5.4 South of Elmira, California · 17 km NE of this epicentre
  4. 5.1 11 km E of Blackhawk, California · 48 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 38.1927, -122.0317. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Solano County, CA 12 km (7 mi) NE earthquakes near Solano County
Contra Costa County, CA 31 km (19 mi) SSE earthquakes near Contra Costa County
Napa County, CA 43 km (27 mi) NW earthquakes near Napa County
Yolo County, CA 55 km (34 mi) NNE earthquakes near Yolo County
Alameda County, CA 62 km (38 mi) S earthquakes near Alameda County
Marin County, CA 64 km (40 mi) WSW earthquakes near Marin County

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

Aftershocks so far

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

  1. 1.5 3km E of Oakland, CA
  2. 2.8 6km WNW of Allendale, CA
  3. 1.5 2km NNE of Pleasant Hill, CA
  4. 1.7 7km SSW of Antioch, CA
  5. 2.1 4km S of Pittsburg, CA
  6. 1.8 9km SSW of Brentwood, CA
  7. 1.9 2km SSE of Pacheco, CA
  8. 3.6 1km ENE of El Cerrito, CA
  9. 1.6 3km E of Oakland, CA
  10. 1.5 4km S of Pittsburg, CA
  11. 1.7 5km E of Vallejo, CA
  12. 1.6 3km NW of Byron, CA
  13. 1.5 9km ESE of Yountville, CA
  14. 1.7 14km E of Angwin, CA
  15. 1.7 5km NNE of Diablo, 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.