Earthquake · reviewed by a seismologist
M 2.5md
Earthquake near San Leandro, CA
No earthquake was likely felt in San Leandro in the 24 hours to 3:59 am PST (11:59 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 2.5 earthquake was recorded 4 km (3 mi) north of San Leandro, CA, at 6:08 pm PST on 4 December 2021 (02:08 UTC), 2.8 km deep. 150 people have reported feeling it to USGS.
USGS: 4km N of San Leandro, CA
6 km (4 mi) E of Oakland, CA
- When
- 6:08 pm PST on 4 December 2021 ()
- Where
- 4 km (3 mi) north of San Leandro, CA · earthquakes near San Leandro
- Magnitude
- M 2.5 (md)
- Depth
- 2.8 km below the surface
- Felt
- 150 reports · strongest reported intensity IV
- Nearest
- Alameda County, 25 km ESE
- Nearest mapped fault
- Hayward fault, 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 1734 days ago
Earthquake alerts for San Leandro, CA
Get a notification in this browser when USGS records an earthquake near San Leandro, CA. No account or email needed.
Alerts are on for .
Not a warning. An alert comes after USGS publishes a quake, usually minutes after the shaking. For early warning use ShakeAlert, through your phone's Wireless Emergency Alerts or the MyShake app.
This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.
At this magnitude and depth, people at rest would likely notice it out to about 22 km (14 mi) from the epicentre. In San Leandro, 4 km away, the estimate is intensity III (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 4 km, intensity III · Alameda 9 km, intensity III · Castro Valley 10 km, intensity III · San Lorenzo 10 km, intensity III · Oakland 11 km, intensity II · Hayward 12 km, intensity II · Orinda 13 km, intensity II · Lafayette 14 km, intensity II. Estimated for each town centre; each link is that town's own record.
How big was it?
This earthquake released about 180 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.5 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 83,000× the energy of this one
- Magna, Utah 2020 M 5.7 59,000× the energy of this one
- Around the size people start to feel M 3.0 5.2× the energy of this one
- This earthquake M 2.5 about 180 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 810 times the energy of this one.
Before 2016, the USGS record lists 6 earthquakes of M5 or more within 50 km; the five largest:
- 7.9 The 1906 San Francisco, California Earthquake · 35 km W of this epicentre
- 5.8 The 1980 Livermore, California Earthquake · 35 km ENE of this epicentre
- 5.5 6 km NNE of East Foothills, California · 50 km SE of this epicentre
- 5.4 9 km NE of Livermore, California · 40 km E of this epicentre
- 5.3 The 1957 San Francisco, California Earthquake · 31 km WSW 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 37.7623, -122.1575. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Alameda County, CA | 25 km (16 mi) | ESE | earthquakes near Alameda County |
| Contra Costa County, CA | 25 km (16 mi) | NE | earthquakes near Contra Costa County |
| San Mateo County, CA | 43 km (27 mi) | SSW | earthquakes near San Mateo County |
| Solano County, CA | 59 km (37 mi) | NNE | earthquakes near Solano County |
| Marin County, CA | 61 km (38 mi) | WNW | earthquakes near Marin County |
| Santa Clara County, CA | 73 km (45 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
55 earthquakes have been recorded within 50 km since this one.
- 2.0 1km NW of Concord, CA
- 1.6 2km NNE of Danville, CA
- 1.7 6km WSW of Daly City, CA
- 2.3 5km E of Blackhawk, CA
- 1.6 4km E of South San Francisco, CA
- 1.9 3km ESE of Pacheco, CA
- 1.7 2km SSW of Blackhawk, CA
- 1.5 5km WSW of Daly City, CA
- 1.6 2km NE of Union City, CA
- 1.8 3km ENE of San Leandro, CA
- 2.9 3km ENE of San Leandro, CA
- 1.6 2km ENE of Pacifica, CA
- 3.2 2km NNE of San Leandro, CA
- 1.6 5km WNW of Byron, CA
- 1.7 5km WNW of Byron, 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
- The official USGS event page — the source of record for every value above
- Did you feel it? Report it to USGS — reports go to USGS, not to us
- ShakeMap for this event, when USGS has produced one
QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.