QuakeIndex

Earthquake · reviewed by a seismologist

M 2.3md

1km NNW of San Pablo, CA

· 5.0 km deep · released about 79 lb of TNT

10 km30 km60 km120 km N Contra Costa County 35 kmMarin County 36 kmSolano County 49 kmAlameda County 53 kmNapa County 60 kmSan Mateo County 62 kmSan Francisco County 66 kmSonoma County 80 kmYolo County 88 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 2.3 (md)
Depth
5.0 km below the surface
Felt
31 reports · strongest reported intensity IV
Nearest
Contra Costa County, 35 km E
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2747 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 31 people have reported feeling it to USGS.

How big was it?

This earthquake released about 79 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.3 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 190,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 130,000× the energy of this one
  3. Around the size people start to feel M 3.0 12× the energy of this one
  4. This earthquake M 2.3 about 79 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 37.9707, -122.3492. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Contra Costa County, CA 35 km (22 mi) W of here earthquakes near Contra Costa County
Marin County, CA 36 km (22 mi) ESE of here earthquakes near Marin County
Solano County, CA 49 km (30 mi) SW of here earthquakes near Solano County
Alameda County, CA 53 km (33 mi) NW of here earthquakes near Alameda County
Napa County, CA 60 km (37 mi) S of here earthquakes near Napa County
San Mateo County, CA 62 km (38 mi) N of here earthquakes near San Mateo County

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

Aftershocks so far

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

  1. 2.0 6km WSW of Colma, CA
  2. 1.5 3km ESE of Rodeo, CA
  3. 2.6 4km ESE of Oakland, CA
  4. 2.9 3km ESE of Berkeley, CA
  5. 1.6 5km SSW of Glen Ellen, CA
  6. 1.5 3km ENE of Oakland, CA
  7. 2.5 10km ESE of Black Point-Green Point, CA
  8. 1.9 10km ESE of Black Point-Green Point, CA
  9. 2.6 10km NNE of Napa, CA
  10. 2.9 4km N of Rodeo, CA
  11. 1.8 2km NE of San Leandro, CA
  12. 1.6 10km ESE of Black Point-Green Point, CA
  13. 2.5 9km ESE of Black Point-Green Point, CA
  14. 2.8 9km ESE of Black Point-Green Point, CA
  15. 2.3 2km SSE of Concord, 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 4.4 on 2018-01-04 — it released about 1,400 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.