QuakeIndex

Earthquake · reviewed by a seismologist

M 4.5mw

1km SSE of Pleasant Hill, CA

· 14 km deep · released about 74 tons of TNT

10 km30 km60 km120 km N Contra Costa County 9 kmAlameda County 35 kmSolano County 38 kmMarin County 62 kmSan Mateo County 64 kmNapa County 68 kmSan Joaquin County 69 kmYolo County 84 kmSacramento 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 4.5 (mw)
Depth
14 km below the surface
Felt
45899 reports · strongest reported intensity VI
Measured shaking
intensity VI (ShakeMap)
USGS impact alert
green
Tsunami
USGS flagged this event for tsunami evaluation. Follow tsunami.gov for official messages.
Nearest
Contra Costa County, 9 km ESE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 370 days ago

This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon. 45899 people have reported feeling it to USGS.

How big was it?

This earthquake released about 74 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.5 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 2,300× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 100× the energy of this one
  3. Magna, Utah 2020 M 5.7 72× the energy of this one
  4. This earthquake M 4.5 about 74 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 150× more

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 37.9380, -122.0570. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Contra Costa County, CA 9 km (6 mi) WNW of here earthquakes near Contra Costa County
Alameda County, CA 35 km (22 mi) NNW of here earthquakes near Alameda County
Solano County, CA 38 km (24 mi) SSW of here earthquakes near Solano County
Marin County, CA 62 km (38 mi) ESE of here earthquakes near Marin County
San Mateo County, CA 64 km (40 mi) NNE of here earthquakes near San Mateo County
Napa County, CA 68 km (42 mi) SSE of here earthquakes near Napa County

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

Aftershocks so far

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

  1. 2.7 10km SE of Livermore, CA
  2. 2.4 2km E of Pacheco, CA
  3. 2.0 1km ESE of Pacheco, CA
  4. 1.9 5km NNW of San Leandro, CA
  5. 1.9 5km NE of Fairview, CA
  6. 1.6 10km ENE of Blackhawk, CA
  7. 1.6 5km NE of Fairview, CA
  8. 1.9 5km W of Dublin, CA
  9. 1.9 6km NE of Alamo, CA
  10. 2.6 3km NW of Castro Valley, CA
  11. 1.6 1km S of Pleasant Hill, CA
  12. 2.2 2km WNW of Orinda, CA
  13. 1.6 3km ESE of Pleasanton, CA
  14. 2.1 2km NE of San Leandro, CA
  15. 1.7 4km NNE of Dublin, 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.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

On USGS

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