QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6md

4km WSW of Daly City, CA

· 11 km deep · released about 7.3 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N San Mateo County 32 kmMarin County 46 kmSan Francisco County 47 kmAlameda County 52 kmContra Costa County 55 kmSolano County 82 kmSanta Cruz County 86 kmSanta Clara County 88 kmNapa County 93 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 1.6 (md)
Depth
11 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
San Mateo County, 32 km SSE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2920 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 7.3 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,500,000× the energy of this one
  3. Around the size people start to feel M 3.0 130× the energy of this one
  4. This earthquake M 1.6 about 7.3 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 37.6813, -122.5067. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
San Mateo County, CA 32 km (20 mi) NNW of here earthquakes near San Mateo County
Marin County, CA 46 km (29 mi) SSE of here earthquakes near Marin County
San Francisco County, CA 47 km (29 mi) E of here earthquakes near San Francisco County
Alameda County, CA 52 km (33 mi) W of here earthquakes near Alameda County
Contra Costa County, CA 55 km (34 mi) WSW of here earthquakes near Contra Costa County
Solano County, CA 82 km (51 mi) SW of here earthquakes near Solano County

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

Aftershocks so far

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

  1. 2.1 5km WSW of San Francisco Zoo, CA
  2. 1.9 2km NNE of Union City, CA
  3. 3.4 3km NNW of Piedmont, CA
  4. 1.9 3km N of Piedmont, CA
  5. 1.8 3km NNW of Piedmont, CA
  6. 3.4 3km NNW of Piedmont, CA
  7. 2.3 4km SSW of Los Altos Hills, CA
  8. 1.8 0km W of Crockett, CA
  9. 2.0 3km NNE of Fairview, CA
  10. 2.0 3km ESE of Berkeley, CA
  11. 2.0 2km ENE of Hayward, CA
  12. 2.0 2km W of Orinda, CA
  13. 2.3 1km NNW of San Pablo, CA
  14. 1.6 5km SW of Dublin, CA
  15. 2.0 3km ENE of San Leandro, 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 15,000 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.