QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6md

Earthquake near San Pablo, CA

No earthquake was likely felt in San Pablo in the 24 hours to 10:22 pm PST (06:22 UTC). The last one was M 1.6, 10 km (6 mi) WNW, at 11:44 am PST on 10 November 2026, estimated intensity II (weak) in town. Every earthquake near San Pablo

This page: a magnitude 1.6 earthquake was recorded in San Pablo, CA, at 2:13 pm PDT on 3 April 2020 (21:13 UTC), 3.0 km deep.

USGS: 1km N of San Pablo, CA

22 km (14 mi) NNE of San Francisco, CA · in Richmond, CA

2:13 pm PDT, Apr 3, 2020 · · 3.0 km deep · released about 7.3 lb of TNT

10 km30 km60 km120 km N Contra Costa County 35 kmMarin County 36 kmSolano County 49 kmAlameda County 52 kmNapa County 60 kmSan Mateo County 62 kmSan Francisco County 66 kmSonoma County 80 kmYolo County 88 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
2:13 pm PDT on 3 April 2020 ()
Where
in San Pablo, CA · earthquakes near San Pablo
Magnitude
M 1.6 (md)
Depth
3.0 km below the surface
Felt
no reports yet
Nearest
Contra Costa County, 35 km E
Nearest mapped fault
Hayward fault, 13 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 2413 days ago

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

At this magnitude and depth, people at rest would likely notice it out to about 11 km (7 mi) from the epicentre. 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.

Likely felt in: San Pablo in town, intensity II · Richmond 4 km, intensity II · Pinole 6 km, intensity II · El Cerrito 7 km, intensity II · Hercules 7 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 7.3 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 2,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,500,000× 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 7.3 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 20,000 times the energy of this one.

Before 2016, the USGS record lists 3 earthquakes of M5 or more within 50 km:

  1. 7.9 The 1906 San Francisco, California Earthquake · 30 km SW of this epicentre
  2. 6.0 The 2014 South Napa, California Earthquake · 28 km N of this epicentre
  3. 5.3 The 1957 San Francisco, California Earthquake · 36 km SSW 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 37.9682, -122.3447. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Contra Costa County, CA 35 km (22 mi) E earthquakes near Contra Costa County
Marin County, CA 36 km (23 mi) WNW earthquakes near Marin County
Solano County, CA 49 km (30 mi) NE earthquakes near Solano County
Alameda County, CA 52 km (32 mi) SE earthquakes near Alameda County
Napa County, CA 60 km (37 mi) N earthquakes near Napa County
San Mateo County, CA 62 km (38 mi) S earthquakes near San Mateo 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. 1.8 2km N of Danville, CA
  2. 2.7 2km SSE of Crockett, CA
  3. 2.3 2km NE of El Cerrito, CA
  4. 2.6 6km SW of Clayton, CA
  5. 2.5 6km NE of Alamo, CA
  6. 1.6 5km E of Vallejo, CA
  7. 2.5 6km W of Yountville, CA
  8. 1.9 6km NE of Alamo, CA
  9. 2.0 3km SW of American Canyon, CA
  10. 2.3 9km NE of Blackhawk, CA
  11. 1.8 1km WNW of Kensington, CA
  12. 1.8 7km N of Orinda, CA
  13. 1.9 5km ENE of Vallejo, CA
  14. 2.1 10km SW of Brentwood, CA
  15. 1.9 2km NNE of Alameda, 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.