QuakeIndex

Earthquake · automatic estimate, may change

M 1.8md

9 km W of Rio Vista, CA

· 23 km deep · released about 16 lb of TNT

Felt it? Tell USGS Check my area
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
Magnitude
M 1.8 (md)
Depth
23 km below the surface
Felt
no reports yet
Nearest
Solano County, 19 km NW
Status
Automatic — a machine’s first estimate, which may change

USGS · last changed by USGS · we first saw it 652 days ago

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

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.

Where

Epicentre 38.1453, -121.7885. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Solano County, CA 19 km (12 mi) SE of here earthquakes near Solano County
Contra Costa County, CA 29 km (18 mi) NNE of here earthquakes near Contra Costa County
San Joaquin County, CA 51 km (32 mi) WNW of here earthquakes near San Joaquin County
Sacramento County, CA 51 km (32 mi) SW of here earthquakes near Sacramento County
Alameda County, CA 56 km (35 mi) N of here earthquakes near Alameda County
Yolo County, CA 60 km (37 mi) S of here 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.

For this area

The largest earthquake within 50 km in our catalogue was M 4.5 on 2019-10-15 — it released about 9,100 times the energy of this one.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.