2.6

M2.6 Earthquake 21 km E of Alum Rock, CASeptember 17, 2026

2026-09-17 03:07:43 UTC (3 hours ago) · approx. 7:07 PM UTC-8 local

MagnitudeM2.6(md)
Time03:07 UTC7:07 PM UTC-8
Depth6.3 kmshallow crustal
Coordinates37.335°, -121.595°
Felt by2DYFI responses
StatusAutomatic (preliminary)

On September 17, 2026 at 03:07 UTC, a magnitude 2.6 shallow crustal earthquake struck 21 km E of Alum Rock, CA, at a depth of 6.3 km and coordinates 37.3352°, -121.5952°.

Physical scale: An earthquake of magnitude 2.6 releases seismic energy equivalent to roughly 128 kg of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 39 m — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at 37.34°, -121.60°

Did You Feel It? — community-reported shaking

Aggregated felt-report intensity from 2 citizen responses to the USGS Did You Feel It? system. Each colored zone represents the average MMI from reports in that area.

USGS DYFI community-reported intensity map for the M2.6 earthquake near 21 km E of Alum Rock, CA

Source: U.S. Geological Survey Did You Feel It?. View on USGS · submit your own report

Earthquake Details

Magnitude
2.6 md
Depth
6.3 km
shallow crustal
Location
37.3352°N
-121.5952°E
Felt Reports
2
DYFI responses
Community Intensity
2.0
CDI from reports

Technical Information

Event ID
nc75437042
Event Type
earthquake
Status
Automatic
Significance
106
Stations Used
74
Azimuthal Gap
64.0°
Min Station Distance
0.038°
RMS Residual
0.08 sec
Last Updated
2026-09-17 05:42:23 UTC

Common Questions

How strong was the magnitude 2.6 earthquake near Alum Rock, CA?

The magnitude 2.6 earthquake that struck 21 km E of Alum Rock, CA on September 17, 2026 at 03:07 UTC had a depth of 6.3 km. For context, this was a minor earthquake typically detected only by instruments.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 2.6 earthquakes can continue for several days and gradually diminish over time.

Understanding This Data

Magnitude 2.6 earthquakes are typically only recorded by instruments.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: nc75437042). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2026, September 17, 2026). M2.6 Earthquake 21 km E of Alum Rock, CASeptember 17, 2026. Retrieved September 17, 2026 from https://www.earthquaketracker.org/earthquakes/event/nc75437042/