QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6md

Earthquake near San Leandro, CA

No earthquake was likely felt in San Leandro in the 24 hours to 1:57 pm PST (21:57 UTC). The last one was M 2.6, 18 km (11 mi) NNW, at 6:23 pm PST on 1 November 2026, estimated intensity II (weak) in town; 114 felt reports to USGS. Every earthquake near San Leandro

This page: a magnitude 1.6 earthquake was recorded 3 km (2 mi) north-northeast of San Leandro, CA, at 2:27 am PST on 3 February 2018 (10:27 UTC), 3.9 km deep.

USGS: 3km NNE of San Leandro, CA

8 km (5 mi) ESE of Oakland, CA · 5 km (3 mi) NNE of San Leandro, CA

2:27 am PST, Feb 3, 2018 · · 3.9 km deep · released about 6.6 lb of TNT

Every earthquake near San Leandro Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Alameda County 23 kmContra Costa County 26 kmSan Mateo County 42 kmSolano County 61 kmMarin County 63 kmSanta Clara County 71 kmSan Francisco County 78 kmSan Joaquin County 79 kmSanta Cruz County 82 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
2:27 am PST on 3 February 2018 ()
Where
3 km (2 mi) north-northeast of San Leandro, CA · earthquakes near San Leandro
Magnitude
M 1.6 (md)
Depth
3.9 km below the surface
Felt
no reports yet
Nearest
Alameda County, 23 km ESE
Nearest mapped fault
Hayward fault, under 1 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 3195 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 10 km (6 mi) from the epicentre. In San Leandro, 3 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.

Likely felt in: San Leandro 3 km, intensity II · Castro Valley 7 km, intensity II · San Lorenzo 8 km, intensity II · Hayward 10 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 6.6 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 2,300,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,600,000× the energy of this one
  3. Around the size people start to feel M 3.0 140× the energy of this one
  4. This earthquake M 1.6 about 6.6 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.

For this area

The largest earthquake within 50 km since 2016 was M 4.4 on 2018-01-04 — about 17,000 times the energy of this one.

Before 2016, the USGS record lists 7 earthquakes of M5 or more within 50 km; the five largest:

  1. 7.9 The 1906 San Francisco, California Earthquake · 36 km W of this epicentre
  2. 5.8 The 1980 Livermore, California Earthquake · 34 km ENE of this epicentre
  3. 5.7 15 km NE of East Foothills, California · 50 km SE of this epicentre
  4. 5.5 6 km NNE of East Foothills, California · 47 km SE of this epicentre
  5. 5.4 9 km NE of Livermore, California · 38 km E 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 37.7450, -122.1407. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Alameda County, CA 23 km (14 mi) ESE earthquakes near Alameda County
Contra Costa County, CA 26 km (16 mi) NE earthquakes near Contra Costa County
San Mateo County, CA 42 km (26 mi) SSW earthquakes near San Mateo County
Solano County, CA 61 km (38 mi) NNE earthquakes near Solano County
Marin County, CA 63 km (39 mi) WNW earthquakes near Marin County
Santa Clara County, CA 71 km (44 mi) SE earthquakes near Santa Clara County

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

Aftershocks so far

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

  1. 1.7 2km W of Diablo, CA
  2. 1.8 2km W of Diablo, CA
  3. 1.6 2km WSW of Diablo, CA
  4. 1.6 2km SW of Diablo, CA
  5. 1.9 2km ENE of Danville, CA
  6. 2.8 2km WSW of Diablo, CA
  7. 3.5 2km ENE of Danville, CA
  8. 3.4 2km ENE of Danville, CA
  9. 1.5 2km SW of Diablo, CA
  10. 1.6 2km E of Danville, CA
  11. 3.3 2km ENE of Danville, CA
  12. 1.6 1km WNW of Diablo, CA
  13. 1.9 2km WSW of Diablo, CA
  14. 2.8 2km WSW of Diablo, CA
  15. 2.0 2km WSW of Diablo, 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.