QuakeIndex

Earthquake · reviewed by a seismologist

M 2.2md

2 km SW of Walnut Creek, CA

· 8.8 km deep · released about 52 lb of TNT

10 km30 km60 km120 km N Contra Costa County 12 kmAlameda County 31 kmSolano County 44 kmSan Mateo County 59 kmMarin County 61 kmSan Joaquin County 71 kmNapa County 72 kmSanta Clara County 82 kmSan Francisco County 85 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 2.2 (md)
Depth
8.8 km below the surface
Felt
13 reports · strongest reported intensity III
Nearest
Contra Costa County, 12 km ENE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 599 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 13 people have reported feeling it to USGS.

How big was it?

This earthquake released about 52 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.2 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 290,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 200,000× the energy of this one
  3. Around the size people start to feel M 3.0 18× the energy of this one
  4. This earthquake M 2.2 about 52 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 37.8900, -122.0815. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Contra Costa County, CA 12 km (7 mi) WSW of here earthquakes near Contra Costa County
Alameda County, CA 31 km (19 mi) NNW of here earthquakes near Alameda County
Solano County, CA 44 km (27 mi) SSW of here earthquakes near Solano County
San Mateo County, CA 59 km (36 mi) NNE of here earthquakes near San Mateo County
Marin County, CA 61 km (38 mi) ESE of here earthquakes near Marin County
San Joaquin County, CA 71 km (44 mi) W of here earthquakes near San Joaquin County

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

Aftershocks so far

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

  1. 1.6 4 km WNW of Dublin, CA
  2. 2.7 5 km W of Dublin, CA
  3. 2.1 4 km W of Dublin, CA
  4. 1.7 5 km WNW of Dublin, CA
  5. 1.8 5 km WSW of Clayton, CA
  6. 1.8 3 km ENE of Oakland, CA
  7. 1.5 6 km SSE of Napa, CA
  8. 1.7 4 km WNW of Dublin, CA
  9. 2.3 3 km W of Danville, CA
  10. 2.3 5 km WNW of Dublin, CA
  11. 2.0 4 km WNW of Dublin, CA
  12. 1.9 4 km WNW of Dublin, CA
  13. 1.5 0 km SSE of San Pablo, CA
  14. 2.3 5 km WNW of Dublin, CA
  15. 2.9 5 km WNW of Dublin, 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 2,800 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.