QuakeIndex

Earthquake · reviewed by a seismologist

M 2.2md

34km W of Bonny Doon, CA

· 7.2 km deep · released about 56 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N San Mateo County 39 kmSanta Cruz County 47 kmSanta Clara County 76 kmAlameda County 83 kmSan Francisco County 84 kmContra Costa County 106 kmMarin County 109 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
7.2 km below the surface
Felt
no reports yet
Nearest
San Mateo County, 39 km NNE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1586 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 56 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 5.8 270,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 190,000× the energy of this one
  3. Around the size people start to feel M 3.0 17× the energy of this one
  4. This earthquake M 2.2 about 56 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 37.0848, -122.5277. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
San Mateo County, CA 39 km (24 mi) SSW of here earthquakes near San Mateo County
Santa Cruz County, CA 47 km (29 mi) W of here earthquakes near Santa Cruz County
Santa Clara County, CA 76 km (47 mi) WSW of here earthquakes near Santa Clara County
Alameda County, CA 83 km (51 mi) SW of here earthquakes near Alameda County
San Francisco County, CA 84 km (52 mi) SSE of here earthquakes near San Francisco County
Contra Costa County, CA 106 km (66 mi) SSW of here earthquakes near Contra Costa County

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

Aftershocks so far

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

  1. 1.6 9 km SW of Loyola, CA
  2. 1.5 10 km SSW of Half Moon Bay, CA
  3. 1.6 7 km SSE of Portola Valley, CA
  4. 1.6 7 km SSE of Portola Valley, CA
  5. 1.6 18 km SSW of Santa Cruz, CA
  6. 1.6 4 km SSW of Lexington Hills, CA
  7. 2.0 3 km W of Half Moon Bay, CA
  8. 1.5 3km SSW of Cupertino, CA
  9. 2.0 7km SSE of Portola Valley, CA
  10. 2.0 2km SE of Portola Valley, CA
  11. 1.9 7km SSE of Portola Valley, CA
  12. 2.1 7km SSE of Portola Valley, CA
  13. 1.7 4km SW of Felton, CA
  14. 1.8 4km SSE of Highlands-Baywood Park, CA
  15. 1.6 1km SSE of Portola Valley, 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.

On USGS

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