QuakeIndex

Earthquake · reviewed by a seismologist

M 1.9md

10km ESE of Sunol, CA

· 8.5 km deep · released about 19 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Alameda County 14 kmSanta Clara County 39 kmContra Costa County 42 kmSan Mateo County 53 kmSan Joaquin County 62 kmSanta Cruz County 64 kmStanislaus County 70 kmSolano County 80 kmMarin County 100 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 1.9 (md)
Depth
8.5 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Alameda County, 14 km NW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2932 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 19 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 810,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 580,000× the energy of this one
  3. Around the size people start to feel M 3.0 51× the energy of this one
  4. This earthquake M 1.9 about 19 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 37.5610, -121.7955. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Alameda County, CA 14 km (9 mi) SE of here earthquakes near Alameda County
Santa Clara County, CA 39 km (24 mi) NNW of here earthquakes near Santa Clara County
Contra Costa County, CA 42 km (26 mi) SSE of here earthquakes near Contra Costa County
San Mateo County, CA 53 km (33 mi) ENE of here earthquakes near San Mateo County
San Joaquin County, CA 62 km (39 mi) SW of here earthquakes near San Joaquin County
Santa Cruz County, CA 64 km (40 mi) NNE of here earthquakes near Santa Cruz County

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

Aftershocks so far

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

  1. 1.6 1km E of San Leandro, CA
  2. 1.7 3km S of Loyola, CA
  3. 2.3 3km ENE of Oakland, CA
  4. 1.6 2km ESE of Pleasanton, CA
  5. 2.0 11km SSE of Portola Valley, CA
  6. 2.5 3km ENE of Oakland, CA
  7. 1.8 10km E of Alum Rock, CA
  8. 1.6 8km NE of Alum Rock, CA
  9. 1.6 11km S of Portola Valley, CA
  10. 1.7 6km NE of Blackhawk, CA
  11. 1.7 3km S of Loyola, CA
  12. 1.6 6km WNW of Mountain House, CA
  13. 1.7 4km SSW of Los Altos Hills, CA
  14. 2.8 6km WNW of Mountain House, CA
  15. 2.5 3km ESE 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 4.1 on 2017-10-10 — it released about 2,200 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.