QuakeIndex

Earthquake · reviewed by a seismologist

M 2.7md

7km NNE of Bay Point, CA

· 23 km deep · released about 350 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Contra Costa County 19 kmSolano County 20 kmAlameda County 49 kmNapa County 57 kmSan Joaquin County 61 kmYolo County 66 kmSacramento County 66 kmMarin County 71 kmSan Mateo 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 2.7 (md)
Depth
23 km below the surface
Felt
7 reports · strongest reported intensity III
Nearest
Contra Costa County, 19 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2921 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 7 people have reported feeling it to USGS.

How big was it?

This earthquake released about 350 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 43,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 31,000× the energy of this one
  3. Around the size people start to feel M 3.0 2.7× the energy of this one
  4. This earthquake M 2.7 about 350 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 38.0887, -121.9417. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Contra Costa County, CA 19 km (12 mi) N of here earthquakes near Contra Costa County
Solano County, CA 20 km (12 mi) S of here earthquakes near Solano County
Alameda County, CA 49 km (31 mi) N of here earthquakes near Alameda County
Napa County, CA 57 km (36 mi) SE of here earthquakes near Napa County
San Joaquin County, CA 61 km (38 mi) WNW of here earthquakes near San Joaquin County
Yolo County, CA 66 km (41 mi) S of here earthquakes near Yolo County

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

Aftershocks so far

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

  1. 2.1 1km N of Vine Hill, CA
  2. 1.5 3km S of Crockett, CA
  3. 2.0 2km S of Discovery Bay, CA
  4. 3.4 3km NNW of Piedmont, CA
  5. 1.9 3km N of Piedmont, CA
  6. 1.8 3km NNW of Piedmont, CA
  7. 3.4 3km NNW of Piedmont, 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. 1.7 1km E of Pacheco, 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 320 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.