QuakeIndex

Earthquake · reviewed by a seismologist

M 1.7md

1km N of Bolinas, CA

· 8.8 km deep · released about 11 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Marin County 15 kmSan Francisco County 37 kmSan Mateo County 63 kmContra Costa County 64 kmSonoma County 70 kmNapa County 72 kmAlameda County 74 kmSolano County 76 kmYolo 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 1.7 (md)
Depth
8.8 km below the surface
Felt
no reports yet
Nearest
Marin County, 15 km NNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1843 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 11 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,400,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,000,000× the energy of this one
  3. Around the size people start to feel M 3.0 89× the energy of this one
  4. This earthquake M 1.7 about 11 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 37.9208, -122.6857. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Marin County, CA 15 km (10 mi) SSE of here earthquakes near Marin County
San Francisco County, CA 37 km (23 mi) NE of here earthquakes near San Francisco County
San Mateo County, CA 63 km (39 mi) NNW of here earthquakes near San Mateo County
Contra Costa County, CA 64 km (40 mi) W of here earthquakes near Contra Costa County
Sonoma County, CA 70 km (44 mi) SSE of here earthquakes near Sonoma County
Napa County, CA 72 km (45 mi) SSW of here earthquakes near Napa County

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

Aftershocks so far

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

  1. 1.7 5km E of Vallejo, CA
  2. 1.6 5km E of Vallejo, CA
  3. 1.6 7km S of Muir Beach, CA
  4. 1.8 3km SW of San Francisco Zoo, CA
  5. 1.5 5km E of Vallejo, CA
  6. 2.1 3km NE of Berkeley, CA
  7. 1.9 4km NNW of Crockett, CA
  8. 1.8 3km W of American Canyon, CA
  9. 2.3 4km SSE of Vallejo, CA
  10. 2.8 1km ENE of El Cerrito, CA
  11. 1.6 5km E of Vallejo, CA
  12. 1.7 6km WSW of Daly City, CA
  13. 1.6 4km E of South San Francisco, CA
  14. 1.5 5km WSW of Daly City, CA
  15. 1.6 4km N of Inverness, 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 10,000 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.