QuakeIndex

Earthquake · reviewed by a seismologist

M 2.0md

3 km SSE of Piedmont, California

· 10 km deep · released about 32 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Contra Costa County 27 kmAlameda County 31 kmSan Mateo County 44 kmMarin County 55 kmSolano County 58 kmSan Francisco County 72 kmSanta Clara County 79 kmNapa County 80 kmSan Joaquin County 84 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
10 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Contra Costa County, 27 km ENE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3526 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 32 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 5.8 470,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 330,000× the energy of this one
  3. Around the size people start to feel M 3.0 30× the energy of this one
  4. This earthquake M 2.0 about 32 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 37.7930, -122.2143. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Contra Costa County, CA 27 km (17 mi) WSW of here earthquakes near Contra Costa County
Alameda County, CA 31 km (19 mi) WNW of here earthquakes near Alameda County
San Mateo County, CA 44 km (28 mi) NNE of here earthquakes near San Mateo County
Marin County, CA 55 km (34 mi) ESE of here earthquakes near Marin County
Solano County, CA 58 km (36 mi) SSW of here earthquakes near Solano County
San Francisco County, CA 72 km (45 mi) E of here earthquakes near San Francisco County

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

Aftershocks so far

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

  1. 1.6 1 km SSE of Livermore, California
  2. 1.6 1 km SSW of Livermore, California
  3. 2.7 2 km SSE of Livermore, California
  4. 2.1 2 km SSE of Livermore, California
  5. 2.0 1 km NE of Diablo, California
  6. 1.9 11 km SW of Brentwood, California
  7. 3.8 8 km E of Blackhawk, California
  8. 2.0 11 km NNW of Pittsburg, California
  9. 1.9 12 km NNE of Bay Point, California
  10. 2.1 10 km N of Bay Point, California
  11. 1.5 5 km ESE of Fremont, California
  12. 1.9 1 km NNE of Pacifica, California
  13. 1.7 4 km SW of Broadmoor, California
  14. 1.6 4 km SW of Broadmoor, California
  15. 1.8 4 km SW of Broadmoor, California

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.