M2.4 Earthquake near Alum Rock, United States — 03 October 2026
A minor earthquake of magnitude 2.4 was recorded near Alum Rock, United States on , with an epicentre 9 km east of Alum Rock, at a focal depth of 5.6 km. It ranked as the 733rd strongest of 6882 earthquakes recorded in the United States in the preceding 30 days.
Time (UTC): 2026-10-03 20:45:59
Time (your timezone): —
Magnitude: 2.4 (minor)
Focal depth: 5.6 km (shallow)
Epicentre: 37.3590, -121.7200
Location: 9 km E of Alum Rock, CA
Country: United States
USGS link to NOAA tsunami information: Not linked
Review status: Automatic
Source: USGS event page
How strong was this earthquake?
Minor earthquakes in this range are felt by people close to the epicentre as a brief jolt or rattle, but they very rarely cause any damage.
A magnitude 2.4 earthquake radiates roughly 60 kg of TNT equivalent in seismic energy.
The USGS assigns this earthquake a significance score of 89, which is below the USGS threshold of more than 600 for its significant-earthquake list. The ranking combines magnitude with available Did You Feel It responses and PAGER alert level; it is not a direct measurement of damage.
What the magnitude scale actually measures →
When it happened locally
That is about 12:39 local solar time at the epicentre, around midday.
This event was shallower than 53% of the 160,222 earthquakes recorded in the United States in our catalogue and stronger than 91% of them.
Where was the epicentre?
The epicentre was located at 37.3590, -121.7200 — 9 km east of Alum Rock. The closest other recorded event was a magnitude 1.2 earthquake 27 km north of here on 03 October 2026.
The nearest other settlements in our records are Alum Rock (6 km south-southeast), Amesti (39 km south), Alamo (58 km north-northwest) and Alameda (64 km northwest).
Why the 6 km depth matters
At 6 km this was a shallow earthquake. Shallow events release their energy close to the surface, so for a given magnitude they produce noticeably stronger shaking — and more damage — than deeper ones. Roughly three quarters of all earthquakes worldwide occur at shallow depths.
This catalogue does not ingest eyewitness responses, so it cannot confirm where this earthquake was felt. Based on magnitude alone, events this small are usually detected by instruments rather than people. Its shallow focus makes stronger surface shaking more likely than for a deeper event of the same magnitude.
Read more on how focal depth changes what you feel →
What does the tsunami information flag mean?
The USGS record does not carry a link to NOAA tsunami information. That field is not an all-clear and does not state whether a tsunami occurred. In this case, a damaging tsunami would be less likely because at M2.4 it falls below the magnitude 6.5 threshold that generally applies before a submarine earthquake displaces enough water to generate a damaging tsunami; it occurred inland rather than beneath the sea floor. For an active coastal alert, use tsunami.gov or your local warning authority.
How earthquakes generate tsunamis, and what the alert levels mean →
Aftershocks and local seismic history
1 further earthquakes have been recorded within about 150 km of the epicentre since this event was recorded, the largest of them magnitude 1.8.
19 earthquakes of magnitude 4 or above have been logged within roughly 200 km of this epicentre in our catalogue. The strongest was a magnitude 4.6 event near Berkeley on 22 September 2025. This M2.4 event released about 1,995 times less energy than that event.
2334 earthquakes have been recorded within 100 km of this epicentre in the past year, 164 of them in the past 30 days.
How long aftershock sequences last, and how large they get →
Where this event sits in the record
This earthquake is part of the October 2026 worldwide record, and of earthquakes in the United States during October 2026. Browse the full monthly archive to compare periods.
Nearest recorded earthquakes to this epicentre
- M1.2 earthquake near Livermore, United States — (27 km N)
- M1.5 earthquake near Pinnacles, United States — (111 km SE)
- M2.4 earthquake near Petaluma, United States — (131 km NW)
- M1.8 earthquake near San Lucas, United States — (159 km SSE)
- M0.3 earthquake near Parkfield, United States — (177 km SE)
- M1.1 earthquake near Anderson Springs, United States — (181 km NNW)
- M1.1 earthquake near The Geysers, United States — (184 km NNW)
- M0.8 earthquake near Parkfield, United States — (185 km SE)
- M0.5 earthquake near The Geysers, United States — (186 km NNW)
- M0.5 earthquake near The Geysers, United States — (187 km NNW)
Other recent earthquakes in the United States
- M2.5 earthquake near Chignik, United States —
- M1.8 earthquake near The Geysers, United States —
- M0.5 earthquake near The Geysers, United States —
- M1.0 earthquake near Corona, United States —
- M1.7 earthquake near Ontario, United States —
- M1.9 earthquake near Ontario, United States —
- M0.8 earthquake near Anza, United States —
- M1.8 earthquake near Pāhala, United States —
- M0.5 earthquake near Ridgecrest, United States —
- M0.6 earthquake near Searles Valley, United States —
Other magnitude 2 earthquakes worldwide
- M2.5 earthquake near Chignik, United States —
- M2.2 earthquake near Denali Park, United States —
- M2.3 earthquake near Volcano, United States —
- M2.3 earthquake near Volcano, United States —
- M2.3 earthquake near Steele, United States —
- M2.6 earthquake near Rachel, United States —
- M2.1 earthquake near Pāhala, United States —
- M2.2 earthquake near Cobb, United States —
Questions about this earthquake
How strong was the earthquake near Alum Rock?
It measured magnitude 2.4 — a minor earthquake. A magnitude 2.4 earthquake radiates roughly 60 kg of TNT equivalent in seismic energy.
How deep was the earthquake near Alum Rock?
The focus was 6 km below the surface, which counts as shallow.
Was the Alum Rock earthquake felt at the surface?
At magnitude 2.4 and a focal depth of 6 km, shaking would have been concentrated near the epicentre.
When did the earthquake near Alum Rock happen?
03 October 2026 at 20:45 UTC.
Was there a tsunami?
No. The USGS record carries no tsunami-information link for this event.
Have there been aftershocks?
1 further earthquakes have been recorded within about 150 km of the epicentre since this event was recorded, the largest of them magnitude 1.8.
How often do earthquakes happen near Alum Rock?
19 earthquakes of magnitude 4 or above have been logged within roughly 200 km of this epicentre in our catalogue. The strongest was a magnitude 4.6 event near Berkeley on 22 September 2025. This M2.4 event released about 1,995 times less energy than that event.