M0.9 earthquake near South San Gabriel, California, United States
A magnitude 0.9 earthquake struck near South San Gabriel, California, United States at 00:20 local time (07:20 UTC) on 4 Oct 2026, at a depth of 17 km, according to USGS.
revised from M1.2
Data: USGS · updated 2026-10-04 14:39 UTC · reviewed
- Magnitude
- 0.9micro
local magnitude (Richter) (ml)
revised from 1.2 - Depth
- 16.8 km
- Status
- Reviewed
- Origin time
- 2026-10-04 07:20:09 UTC
- Local: 4 Oct 2026, 00:20:09 (America/Los Angeles)
- Epicentre
- 34.029° N, 118.085° 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
| Place | Distance | Est. shaking |
|---|---|---|
| South San GabrielCalifornia, United States · pop. 8,070 | 2 km | INot felt |
| MontebelloCalifornia, United States · pop. 63,921 | 3 km | INot felt |
| South El MonteCalifornia, United States · pop. 20,878 | 4 km | INot felt |
| Monterey ParkCalifornia, United States · pop. 61,468 | 5 km | INot felt |
| West Whittier-Los NietosCalifornia, United States · pop. 25,540 | 6 km | INot felt |
| Los AngelesCalifornia, United States · pop. 3,820,914 | 14 km | INot felt |
| AnaheimCalifornia, United States · pop. 350,742 | 27 km | INot felt |
| Long BeachCalifornia, United States · pop. 474,140 | 30 km | INot 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.
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 · CI, which has been reviewed by an analyst.
| Agency | Magnitude | Depth | Epicentre | Time offset | Status |
|---|---|---|---|---|---|
| USGS · CIheadlineSouthern California Seismic Network via U.S. Geological Survey | 0.9 mlwas 1.2 | 16.8 km | 34.03° N, 118.08° W | – | Reviewed · 2 revisions |
How big was it?
Usually not felt. Recorded by nearby seismometers; thousands occur worldwide every day.
It released roughly the energy of 401 g 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 17 km this was a shallow earthquake, which is felt more strongly at the surface than a deeper one of the same size.
M1.0 releases about 1.2× the energy of M0.9, and its waves are about 1.1× taller on a seismogram. Energy: 477 g of TNT vs 401 g of TNT.
Each square is the energy of one M0.9. Energy from log₁₀E = 1.5M + 4.8.
Aftershocks and nearby activity
29 later earthquakes within 30 km; the largest was M3.2 34 days ago. 3 in the 7 days before. Aftershock rates usually fall off roughly in proportion to 1/time.
Mainshock M0.9
29 later earthquakes nearby. Aftershock rates typically fall off roughly as 1/time (Omori's law).
| Time after mainshock (hours) | Magnitude | Depth (km) |
|---|---|---|
| 2.35 | 0.9 | 3 |
| 25.75 | 1.2 | 21 |
| 35.07 | 0.7 | 13 |
| 100.46 | 1.5 | 11 |
| 120.40 | 3.2 | 12 |
| 233.28 | 0.5 | 11 |
| 356.81 | 0.6 | 13 |
| 372.52 | 1.2 | -1 |
| 374.69 | 0.9 | 7 |
| 411.03 | 1.2 | 7 |
| 449.14 | 0.8 | 11 |
| 498.68 | 1.2 | 12 |
| 525.43 | 1.1 | 8 |
| 541.94 | 1.0 | -1 |
| 572.23 | 1.1 | 11 |
| 573.02 | 1.7 | 11 |
| 575.74 | 0.9 | 11 |
| 579.41 | 0.7 | 9 |
| 579.97 | 0.8 | 11 |
| 582.34 | 0.7 | 10 |
| 583.02 | 0.7 | 11 |
| 583.13 | 0.8 | 10 |
| 584.15 | 1.3 | 11 |
| 612.75 | 0.8 | 9 |
| 627.03 | 1.1 | 11 |
| 647.40 | 0.9 | 13 |
| 652.60 | 0.5 | 7 |
| 662.19 | 1.8 | 12 |
| 687.77 | 1.2 | 12 |
- 3.2Near Signal Hill, California, United States10-09 07:44
- 1.8Near West Rancho Dominguez, California, United States10-31 21:31
- 1.73 km S of Glendale, California, United States10-28 04:21
- 1.5Near Mayflower Village, California, United States10-08 11:47
- 1.36 km NE of Los Angeles, California, United States10-28 15:29
- 1.2Near Stanton, California, United States10-25 02:00
- 1.212 km ENE of Santa Monica, California, United States10-21 10:21
- 1.26 km NNW of Glendora, California, United States11-01 23:06
- 1.2Near Pico Rivera, California, United States10-05 09:04
- 1.26 km NNW of Azusa, California, United States10-19 19:51
- 1.14 km S of Glendale, California, United States10-28 03:34
- 1.1Near South El Monte, California, United States10-30 10:21
- 1.1Near Anaheim, California, United States10-26 04:46
- 1.05 km NNW of Azusa, California, United States10-26 21:16
- 0.9Near Alhambra, California, United States10-19 22:01
- 0.94 km S of San Dimas, California, United States10-31 06:44
- 0.9Near Charter Oak, California, United States10-04 09:41
- 0.94 km S of Glendale, California, United States10-28 07:04
- 0.83 km NNW of Sierra Madre, California, United States10-23 00:28
- 0.85 km N of Inglewood, California, United States10-29 20:05
- 0.83 km SSW of Glendale, California, United States10-28 11:18
- 0.83 km SSW of Glendale, California, United States10-28 14:28
- 0.7Near South Pasadena, California, United States10-05 18:24
- 0.73 km SSW of Glendale, California, United States10-28 13:40
- 0.74 km SSW of Glendale, California, United States10-28 14:21
Did you feel it?
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Reports on SeismoAtlas
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Event id ci41342855. First recorded here 4 Oct 2026, 07:22:59 UTC. Solutions: USGS · CI (usgs:ci41342855). Cite as: SeismoAtlas, “M0.9 earthquake near South San Gabriel, California, United States”, https://seismoatlas.com/earthquake/ci41342855-m0-9-earthquake-near-south-san-gabriel-california-united-states, data from USGS.
JSON: /api/v1/events/ci41342855. SeismoAtlas is not an official warning service.