QuakeIndex

Earthquake · automatic estimate, may change

M 1.8md

Earthquake near Rio Vista, CA

No earthquake was likely felt in Rio Vista in the 24 hours to 10:08 pm PST (06:08 UTC). The last one was M 3.1, 35 km (22 mi) SSW, at 12:25 am PDT on 12 September 2026, estimated intensity II (weak) in town; 257 felt reports to USGS. Every earthquake near Rio Vista

This page: a magnitude 1.8 earthquake was recorded 8 km (5 mi) west-southwest of Rio Vista, CA, at 1:59 am PST on 14 December 2024 (09:59 UTC), 23 km deep. The magnitude and location are an automatic first estimate and may change.

USGS: 9 km W of Rio Vista, CA

69 km (43 mi) NE of San Francisco, CA · 17 km (11 mi) NNE of Pittsburg, CA

1:59 am PST, Dec 14, 2024 · · 23 km deep · released about 16 lb of TNT

10 km30 km60 km120 km N Solano County 19 kmContra Costa County 29 kmSan Joaquin County 51 kmSacramento County 51 kmAlameda County 56 kmYolo County 60 kmNapa County 62 kmMarin County 84 kmStanislaus County 95 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
1:59 am PST on 14 December 2024 ()
Where
8 km (5 mi) west-southwest of Rio Vista, CA · earthquakes near Rio Vista
Magnitude
M 1.8 (md)
Depth
23 km below the surface
Felt
no reports yet
Nearest
Solano County, 19 km NW
Nearest mapped fault
Great Valley thrust fault system, 21 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 698 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 Rio Vista, 8 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: Pittsburg, Antioch, Oakley, Bethel Island, Bay Point, Knightsen.

How big was it?

This earthquake released about 16 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 930,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 660,000× the energy of this one
  3. Around the size people start to feel M 3.0 59× the energy of this one
  4. This earthquake M 1.8 about 16 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 9,100 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 · 46 km W of this epicentre
  2. 5.8 The 1980 Livermore, California Earthquake · 34 km S of this epicentre
  3. 5.4 South of Elmira, California · 20 km NNW of this epicentre
  4. 5.4 9 km NE of Livermore, California · 45 km S of this epicentre
  5. 5.1 11 km E of Blackhawk, California · 37 km S 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 38.1453, -121.7885. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Solano County, CA 19 km (12 mi) NW earthquakes near Solano County
Contra Costa County, CA 29 km (18 mi) SSW earthquakes near Contra Costa County
San Joaquin County, CA 51 km (32 mi) ESE earthquakes near San Joaquin County
Sacramento County, CA 51 km (32 mi) NE earthquakes near Sacramento County
Alameda County, CA 56 km (35 mi) S earthquakes near Alameda County
Yolo County, CA 60 km (37 mi) N earthquakes near Yolo County

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

Aftershocks so far

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

  1. 1.8 5 km WSW of Clayton, CA
  2. 1.5 6 km SSE of Napa, CA
  3. 2.3 3 km W of Danville, CA
  4. 1.6 5 km E of Vallejo, CA
  5. 2.1 12 km NNE of Bay Point, CA
  6. 2.3 0 km SSW of Concord, CA
  7. 1.7 4 km W of Alamo, CA
  8. 2.5 4 km W of Alamo, CA
  9. 2.5 4 km W of Alamo, CA
  10. 1.7 13 km NNE of Pittsburg, CA
  11. 1.6 1 km S of Pacheco, CA
  12. 1.5 7 km E of Vallejo, CA
  13. 1.8 3 km ESE of Pacheco, CA
  14. 1.8 6 km SW of Clayton, CA
  15. 1.6 3 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.