QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6md

4 km SSW of Byron, California

· 3.5 km deep · released about 6.4 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Contra Costa County 28 kmAlameda County 30 kmSan Joaquin County 36 kmSolano County 55 kmStanislaus County 65 kmSanta Clara County 67 kmSacramento County 75 kmSan Mateo County 78 kmSanta Cruz County 96 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
3.5 km below the surface
Felt
no reports yet
Nearest
Contra Costa County, 28 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3347 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 6.4 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,400,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,700,000× the energy of this one
  3. Around the size people start to feel M 3.0 150× the energy of this one
  4. This earthquake M 1.6 about 6.4 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 37.8250, -121.6575. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Contra Costa County, CA 28 km (17 mi) ESE of here earthquakes near Contra Costa County
Alameda County, CA 30 km (19 mi) NE of here earthquakes near Alameda County
San Joaquin County, CA 36 km (22 mi) WSW of here earthquakes near San Joaquin County
Solano County, CA 55 km (34 mi) SSE of here earthquakes near Solano County
Stanislaus County, CA 65 km (40 mi) WNW of here earthquakes near Stanislaus County
Santa Clara County, CA 67 km (42 mi) N of here earthquakes near Santa Clara County

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

Aftershocks so far

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

  1. 1.7 11 km SSE of Livermore, California
  2. 1.9 6 km ENE of East Foothills, California
  3. 1.6 2 km W of Danville, California
  4. 2.0 2 km WSW of Clyde, California
  5. 1.7 1 km SSW of Clyde, California
  6. 1.7 1 km SW of Clyde, California
  7. 2.3 2 km WSW of Clyde, California
  8. 1.5 1 km SSE of Clyde, California
  9. 1.7 1 km WNW of Concord, California
  10. 1.7 7 km W of San Ramon, California
  11. 2.7 8 km SE of Livermore, California
  12. 1.9 7 km SE of Livermore, California
  13. 2.0 8 km NNE of East Foothills, California
  14. 1.8 Northern California
  15. 2.5 9 km NNE of East Foothills, California

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.

On USGS

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