QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6md

1km NE of Byron, CA

· 4.1 km deep · released about 7.6 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Contra Costa County 28 kmSan Joaquin County 32 kmAlameda County 35 kmSolano County 51 kmStanislaus County 65 kmSacramento County 69 kmSanta Clara County 73 kmSan Mateo County 83 kmYolo 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
4.1 km below the surface
Felt
no reports yet
Nearest
Contra Costa County, 28 km W
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1707 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 7.6 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 2,000,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,400,000× 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 7.6 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 37.8727, -121.6333. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Contra Costa County, CA 28 km (18 mi) E of here earthquakes near Contra Costa County
San Joaquin County, CA 32 km (20 mi) WSW of here earthquakes near San Joaquin County
Alameda County, CA 35 km (22 mi) NE of here earthquakes near Alameda County
Solano County, CA 51 km (32 mi) SSE of here earthquakes near Solano County
Stanislaus County, CA 65 km (41 mi) WNW of here earthquakes near Stanislaus County
Sacramento County, CA 69 km (43 mi) SSW of here earthquakes near Sacramento County

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

Aftershocks so far

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

  1. 4.1 7km NW of Bay Point, CA
  2. 1.8 2km SE of Danville, CA
  3. 2.0 24km NE of Alum Rock, CA
  4. 1.8 3km NNE of San Ramon, CA
  5. 1.7 3km S of Diablo, CA
  6. 1.9 2km N of Castro Valley, CA
  7. 1.8 11km NE of Milpitas, CA
  8. 2.4 8km SW of Brentwood, CA
  9. 2.6 24km NE of Alum Rock, CA
  10. 2.3 10km SW of Brentwood, CA
  11. 1.6 10km ENE of Blackhawk, CA
  12. 1.8 3km S of Pittsburg, CA
  13. 1.9 5km ESE of Moraga, CA
  14. 2.7 4km S of Pittsburg, CA
  15. 1.9 6km SW of Clayton, 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 4.5 on 2019-10-15 — it released about 19,000 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.