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M1.4 earthquake 4 km N of San Leandro, California, United States

A magnitude 1.4 earthquake struck 4 km N of San Leandro, California, United States at 21:54 local time (04:54 UTC) on 21 Sept 2026, at a depth of 0 km, according to USGS. The solution is preliminary and may be revised.

Data: USGS · updated 2026-09-22 05:47 UTC · automatic solution

Magnitude
1.4micro
duration magnitude (md)
Depth
-0.3 km
Status
Automatic
Origin time
2026-09-22 04:54:30 UTC
Local: 21 Sept 2026, 21:54:30 (America/Los Angeles)
Epicentre
37.757° N, 122.165° W

Circles show this event and others within 30 km from 7 days before to 30 days after. Lines: plate boundaries and GEM active faults. Open on the live map

Nearby places

Distance and estimated shaking at nearby places
PlaceDistanceEst. shaking
San LeandroCalifornia, United States · pop. 90,7124 kmIIWeak
AlamedaCalifornia, United States · pop. 78,6308 kmINot felt
AshlandCalifornia, United States · pop. 21,9259 kmINot felt
Castro ValleyCalifornia, United States · pop. 61,38810 kmINot felt
OaklandCalifornia, United States · pop. 419,26710 kmINot felt
San FranciscoCalifornia, United States · pop. 827,52622 kmINot felt
San JoseCalifornia, United States · pop. 997,36852 kmINot felt
StocktonCalifornia, United States · pop. 305,65880 kmINot felt

Shaking is an estimate from the intensity prediction equation of Allen, Wald & Worden (2012), not an observation. Local ground and buildings can change it by a level or more. Likely felt out to about 3 km.

Every agency's solution

Agencies locate earthquakes with their own stations and methods, so their numbers differ. We match reports of the same event by time, distance and magnitude and show them side by side. The headline uses USGS · NC.

AgencyMagnitudeDepthEpicentreTime offsetStatus
USGS · NCheadlineNorthern California Seismic System via U.S. Geological Survey1.4 md-0.3 km37.76° N, 122.17° W–Automatic

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How big was it?

Usually not felt. Recorded by nearby seismometers; thousands occur worldwide every day.

It released roughly the energy of 2 kg of TNT. Magnitude is logarithmic: each whole step means about 32 times more energy and 10 times larger waves on a seismogram. Depth matters too: at 0 km this was a shallow earthquake, which is felt more strongly at the surface than a deeper one of the same size.

M1.4 releases about 4.6× the energy of M1.0, and its waves are about 2.8× taller on a seismogram. Energy: 2 kg of TNT vs 477 g of TNT.

Each square is the energy of one M1.0. Energy from log₁₀E = 1.5M + 4.8.

Aftershocks and nearby activity

4 later earthquakes within 30 km; the largest was M2.3 2 days ago. Aftershock rates usually fall off roughly in proportion to 1/time.

Aftershocks

Mainshock M1.4

4 later earthquakes nearby. Aftershock rates typically fall off roughly as 1/time (Omori's law).

Aftershocks
Time after mainshock (hours)MagnitudeDepth (km)
75.621.18
108.782.34
125.901.68
161.201.78
  1. 2.34 km WNW of Orinda, California, United States09-26 17:41
  2. 1.7Near San Ramon, California, United States09-28 22:06
  3. 1.6Near San Ramon, California, United States09-27 10:48
  4. 1.1Near Danville, California, United States09-25 08:31

Did you feel it?

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Reports on SeismoAtlas

No reports yet.

Event id nc75439847. First recorded here 28 Sept 2026, 17:32:12 UTC. Solutions: USGS · NC (usgs:nc75439847). Cite as: SeismoAtlas, “M1.4 earthquake 4 km N of San Leandro, California, United States”, https://seismoatlas.com/earthquake/nc75439847-m1-4-earthquake-4-km-n-of-san-leandro-california-united-states, data from USGS.

JSON: /api/v1/events/nc75439847. SeismoAtlas is not an official warning service.