3.5

M3.5 Earthquake 6 km NW of Fontana, CANovember 16, 2024

2024-11-16 22:17:04 UTC (2024-11-16) · approx. 2:17 PM UTC-8 local

Felt by 499 people across surrounding communities. Maximum shaking intensity MMI 4.1 (moderate).

MagnitudeM3.5(mw)
Time22:17 UTC2:17 PM UTC-8
Depth2.8 kmshallow crustal
Coordinates34.142°, -117.500°
Felt by499DYFI responses· max MMI 4.1
Status✓ Reviewed by USGS

On November 16, 2024 at 22:17 UTC, a magnitude 3.5 shallow crustal earthquake struck 6 km NW of Fontana, CA, at a depth of 2.8 km and coordinates 34.1425°, -117.5002°. The earthquake was reported felt by 499 peopleacross surrounding communities, with a maximum shaking intensity of Modified Mercalli Intensity (MMI) 4.1 (moderate). This earthquake was detected by 154 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 400, placing it among routine seismic activity.

Physical scale: An earthquake of magnitude 3.5 releases seismic energy equivalent to roughly 2.4 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 149 m — a useful intuition for the size of the slip patch on the fault.

The epicenter is located in California, a region characterized by the San Andreas transform fault system, where the Pacific and North American plates slide past each other at roughly 46 mm per year. The nearest mapped fault system is the San Andreas Fault. View all earthquakes in California.

Learn more: San Andreas Fault · Magnitude scale · Aftershock sequences

What the Shaking Felt Like

At MMI 4.1 (moderate), people in the most strongly affected areas would have experienced: Mild shaking, similar to a passing truck. Hanging objects swing. Glasses and dishes may rattle. Not commonly felt outdoors.

Map showing earthquake epicenter at 34.14°, -117.50°

ShakeMap — predicted shaking intensity

Modeled ground-motion intensity contoured on the Modified Mercalli scale (MMI). Computed by the USGS from the moment-tensor solution and regional ground-motion prediction equations.

USGS ShakeMap intensity contours for the M3.5 earthquake near 6 km NW of Fontana, CA

Source: U.S. Geological Survey ShakeMap. View interactive ShakeMap on USGS

Did You Feel It? — community-reported shaking

Aggregated felt-report intensity from 499 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 M3.5 earthquake near 6 km NW of Fontana, CA

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

Earthquake Details

Magnitude
3.5 mw
Depth
2.8 km
shallow crustal
Location
34.1425°N
-117.5002°E
Felt Reports
499
DYFI responses
Intensity (MMI)
4.1
moderate
Community Intensity
4.3
CDI from reports

Technical Information

Event ID
ci40794295
Event Type
earthquake
Status
✓ Reviewed
Significance
400
Stations Used
154
Azimuthal Gap
21.0°
Min Station Distance
0.038°
RMS Residual
0.24 sec
Last Updated
2026-03-18 21:52:19 UTC

Common Questions

How strong was the magnitude 3.5 earthquake near Fontana, CA?

The magnitude 3.5 earthquake that struck 6 km NW of Fontana, CA on November 16, 2024 at 22:17 UTC had a depth of 2.8 km. It was felt by 499 people with maximum shaking intensity of MMI 4.1 (moderate). For context, this was a minor earthquake typically detected only by instruments.

Where did the earthquake occur?

The earthquake epicenter was located at 34.1425°, -117.5002°, which is 6 km NW of Fontana, CA. View all earthquakes in California.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 3.5 earthquakes can continue for several days and gradually diminish over time.

Has California had earthquakes this big before?

The largest recorded earthquake in California was the M7.9 Fort Tejon earthquake of January 9, 1857. Today's magnitude 3.5 event is significantly smaller than that historical record.

Authoritative source: USGS event page (event ID: ci40794295). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2024, November 16, 2024). M3.5 Earthquake 6 km NW of Fontana, CANovember 16, 2024. Retrieved March 18, 2026 from https://www.earthquaketracker.org/earthquakes/event/ci40794295/