QuakeIndex

Earthquake · reviewed by a seismologist

M 2.0md

5km SW of Danville, CA

· 9.1 km deep · released about 36 lb of TNT

10 km30 km60 km120 km N Contra Costa County 16 kmAlameda County 20 kmSan Mateo County 51 kmSolano County 54 kmMarin County 68 kmSan Joaquin County 69 kmSanta Clara County 70 kmNapa County 83 kmSanta Cruz County 87 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 2.0 (md)
Depth
9.1 km below the surface
Felt
1 report · strongest reported intensity I
Nearest
Contra Costa County, 16 km NNE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2067 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 1 person has reported feeling it to USGS.

How big was it?

This earthquake released about 36 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 5.8 420,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 300,000× the energy of this one
  3. Around the size people start to feel M 3.0 27× the energy of this one
  4. This earthquake M 2.0 about 36 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 37.7915, -122.0387. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Contra Costa County, CA 16 km (10 mi) SSW of here earthquakes near Contra Costa County
Alameda County, CA 20 km (12 mi) NW of here earthquakes near Alameda County
San Mateo County, CA 51 km (32 mi) NE of here earthquakes near San Mateo County
Solano County, CA 54 km (33 mi) S of here earthquakes near Solano County
Marin County, CA 68 km (43 mi) ESE of here earthquakes near Marin County
San Joaquin County, CA 69 km (43 mi) WSW 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

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

  1. 1.6 2km W of Concord, CA
  2. 1.5 0km NW of Danville, CA
  3. 1.6 4km NNW of Pacifica, CA
  4. 2.1 1km WNW of Danville, CA
  5. 2.8 2km N of Piedmont, CA
  6. 1.5 5km E of Vallejo, CA
  7. 1.7 7km W of Newark, CA
  8. 2.5 2km N of Piedmont, CA
  9. 1.8 3km WSW of Oakley, CA
  10. 1.8 3km S of Concord, CA
  11. 2.3 6km WSW of Colma, CA
  12. 2.2 14km SE of Livermore, CA
  13. 1.5 9km ENE of Milpitas, CA
  14. 2.1 3km WNW of Pacifica, CA
  15. 2.0 9km ENE of Milpitas, 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 4,100 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.