QuakeIndex

Earthquake · reviewed by a seismologist

M 2.0md

Earthquake near Vacaville, CA

No earthquake was likely felt in Vacaville in the 24 hours to 6:46 pm PST (02:46 UTC). The last one was M 3.8, 68 km (42 mi) SSW, at 8:30 am PDT on 13 August 2026, estimated intensity II (weak) in town; 7,876 felt reports to USGS. Every earthquake near Vacaville

This page: a magnitude 2.0 earthquake was recorded 3 km (2 mi) south-southeast of Vacaville, CA, at 3:31 pm PST on 15 January 2024 (23:31 UTC), 21 km deep.

USGS: 3 km SSE of Vacaville, CA

in Vacaville, CA

3:31 pm PST, Jan 15, 2024 · · 21 km deep · released about 33 lb of TNT

10 km30 km60 km120 km N Solano County 8 kmNapa County 37 kmYolo County 39 kmContra Costa County 46 kmSacramento County 56 kmMarin County 75 kmSan Joaquin County 75 kmAlameda County 76 kmSutter County 81 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
3:31 pm PST on 15 January 2024 ()
Where
3 km (2 mi) south-southeast of Vacaville, CA · earthquakes near Vacaville
Magnitude
M 2.0 (md)
Depth
21 km below the surface
Felt
no reports yet
Nearest
Solano County, 8 km SSE
Nearest mapped fault
Great Valley thrust fault system, 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 1024 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 Vacaville, 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.

Earthquakes near other towns within 30 km: Hartley, Fairfield, Suisun, Allendale, Dixon, Green Valley.

How big was it?

This earthquake released about 33 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 5.8 450,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 320,000× the energy of this one
  3. Around the size people start to feel M 3.0 29× the energy of this one
  4. This earthquake M 2.0 about 33 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 4,400 times the energy of this one.

Before 2016, the USGS record lists 2 earthquakes of M5 or more within 50 km:

  1. 6.0 The 2014 South Napa, California Earthquake · 33 km WSW of this epicentre
  2. 5.4 South of Elmira, California · 7 km ESE 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 38.3335, -121.9698. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Solano County, CA 8 km (5 mi) SSE earthquakes near Solano County
Napa County, CA 37 km (23 mi) WNW earthquakes near Napa County
Yolo County, CA 39 km (24 mi) N earthquakes near Yolo County
Contra Costa County, CA 46 km (29 mi) S earthquakes near Contra Costa County
Sacramento County, CA 56 km (35 mi) ENE earthquakes near Sacramento County
Marin County, CA 75 km (46 mi) WSW earthquakes near Marin County

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

Aftershocks so far

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

  1. 1.5 5 km E of Vallejo, CA
  2. 1.6 16 km NE of Napa, CA
  3. 2.5 4 km SW of Antioch, CA
  4. 2.1 4 km SW of Antioch, CA
  5. 2.4 7 km S of Temelec, CA
  6. 1.5 5 km E of Vallejo, CA
  7. 1.7 8 km E of Angwin, CA
  8. 2.3 7 km E of Angwin, CA
  9. 1.7 5 km E of Vallejo, CA
  10. 1.6 6 km ENE of Vallejo, CA
  11. 1.5 6 km E of Walnut Creek, CA
  12. 1.6 14 km NNE of Napa, CA
  13. 1.7 1 km W of Pacheco, CA
  14. 2.0 10 km ESE of Clayton, CA
  15. 1.5 3 km NE of Saint Helena, 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.