QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

Earthquake near Brentwood, CA

No earthquake was likely felt in Brentwood in the 24 hours to 2:06 pm PST (22:06 UTC). The last one was M 3.0, 12 km (7 mi) WSW, at 6:47 am PDT on 14 September 2026, estimated intensity II (weak) in town; 52 felt reports to USGS. Every earthquake near Brentwood

This page: a magnitude 2.1 earthquake was recorded 13 km (8 mi) south-southwest of Brentwood, CA, at 1:57 pm PST on 13 January 2022 (21:57 UTC), 18 km deep.

USGS: 11km SSW of Brentwood, CA

12 km (8 mi) SSW of Brentwood, CA · 60 km (37 mi) N of San Jose, CA

1:57 pm PST, Jan 13, 2022 · · 18 km deep · released about 40 lb of TNT

10 km30 km60 km120 km N Contra Costa County 19 kmAlameda County 24 kmSan Joaquin County 45 kmSolano County 51 kmSanta Clara County 68 kmSan Mateo County 70 kmStanislaus County 74 kmSacramento County 78 kmMarin County 89 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
1:57 pm PST on 13 January 2022 ()
Where
13 km (8 mi) south-southwest of Brentwood, CA · earthquakes near Brentwood
Magnitude
M 2.1 (md)
Depth
18 km below the surface
Felt
no reports yet
Nearest
Contra Costa County, 19 km WNW
Nearest mapped fault
Greenville fault, 4 km from its surface trace — near is not the same as on
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1757 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth it was probably too small to be felt, even directly above it. In Brentwood, 13 km away, the estimate is intensity II (weak). Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.

Earthquakes near other towns within 30 km: Byron, Blackhawk, Livermore, Diablo, Discovery Bay, Knightsen.

How big was it?

This earthquake released about 40 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 380,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 270,000× the energy of this one
  3. Around the size people start to feel M 3.0 24× the energy of this one
  4. This earthquake M 2.1 about 40 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.

For this area

The largest earthquake within 50 km since 2016 was M 4.5 on 2019-10-15 — about 3,700 times the energy of this one.

Before 2016, the USGS record lists 6 earthquakes of M5 or more within 50 km; the five largest:

  1. 5.8 The 1980 Livermore, California Earthquake · 1 km N of this epicentre
  2. 5.7 15 km NE of East Foothills, California · 40 km S of this epicentre
  3. 5.5 6 km NNE of East Foothills, California · 44 km S of this epicentre
  4. 5.4 9 km NE of Livermore, California · 11 km SSE of this epicentre
  5. 5.3 6 km E of East Foothills, California · 49 km S of this epicentre

Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.

Where

Epicentre 37.8303, -121.7673. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Contra Costa County, CA 19 km (12 mi) WNW earthquakes near Contra Costa County
Alameda County, CA 24 km (15 mi) SSW earthquakes near Alameda County
San Joaquin County, CA 45 km (28 mi) ENE earthquakes near San Joaquin County
Solano County, CA 51 km (32 mi) NNW earthquakes near Solano County
Santa Clara County, CA 68 km (42 mi) S earthquakes near Santa Clara County
San Mateo County, CA 70 km (44 mi) SW earthquakes near San Mateo County

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

Aftershocks so far

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

  1. 1.9 6km SW of Clayton, CA
  2. 1.6 4km SW of San Ramon, CA
  3. 1.6 4km SW of San Ramon, CA
  4. 1.6 2km E of Pleasant Hill, CA
  5. 1.7 5km E of Vallejo, CA
  6. 1.7 10km ENE of Milpitas, CA
  7. 1.6 5km E of Fremont, CA
  8. 1.7 10km ESE of Clayton, CA
  9. 1.6 5km E of Vallejo, CA
  10. 2.0 9km NE of Blackhawk, CA
  11. 1.5 5km E of Vallejo, CA
  12. 2.3 5km NNE of Alum Rock, CA
  13. 2.0 2km E of Pacheco, CA
  14. 2.2 2km NW of Diablo, CA
  15. 2.1 3km NE of Berkeley, 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.

On USGS

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