M 3.3 - 17 km WSW of Petrolia, CA

Source: USGS · Northern California

A magnitude 3.3 earthquake was recorded by USGS near 17 km WSW of Petrolia. On the USGS Earthquake Hazards Program scale, M3.3 is classified "Minor". Among the 1,720 earthquake reports Areazine has published, this M3.3 event ranks stronger than 21% of them (rank #1,270 by magnitude).

The earthquake report, at a glance

Magnitude
M 3.3
USGS class
Minor
Location
17 km WSW of Petrolia
Archive rank
#1,270 of 1,720
Source
USGS
Published
September 15, 2026
MINOR

Out of 1,720 earthquake reports Areazine has logged, this one outranks 21% of them — 1,269 recorded a higher magnitude.

Record status: USGS's reading at the moment of detection — the agency keeps revising magnitude, aftershock counts, and felt reports on its own event page as more data arrives.

What Happened

A magnitude 3.28 ml earthquake occurred 17 km WSW of Petrolia, CA, on September 15, 2026, at 12:38:06 UTC. The event registered a depth of 8.99 km.

Location Details

The epicenter was located at coordinates 40.2935°N, 124.485°W, approximately 17 km west-southwest of Petrolia, CA. The shallow depth of 8.99 km classifies this as a shallow earthquake (less than 20 km).

Impact Assessment

No felt reports were recorded for this event. There was no tsunami advisory (tsunami flag: 0) and no alert level assigned.

What You Should Know

This was a minor earthquake (M 2.5-3.9), which is often felt but rarely causes damage. Residents in the area should be aware of the possibility of aftershocks.

Source

Data from USGS: https://earthquake.usgs.gov/earthquakes/eventpage/nc75435962

Original source: USGS Official Notice ↗

All Earthquakes →

Nationwide notices with similar length or severity timing 8

Beyond this USGS earthquake report's own category, Areazine surfaces two nationwide peer sets: length-matched and severity/date-matched notices from elsewhere in the archive, distinct from the same-feed Related list above.

What People Ask

What people usually ask about a notice like this one.

How strong was this earthquake?
A magnitude 3.3 earthquake struck 17 km west-southwest of Petrolia, California, at a shallow depth of 9 km.
How should a magnitude 3.3 ("Minor") event be understood?
The USGS classifies M3.3 as "Minor" on its Earthquake Hazards Program scale. Events in this range are rarely felt beyond the immediate epicenter and typically cause no damage; most are recorded only by seismographs.
Is this earthquake stronger or weaker than others in the archive?
This is the #1,270 strongest of the 1,720 earthquake reports in Areazine's archive by magnitude, stronger than 21% of them and weaker than 1,269 others.
Was Petrolia likely to feel this earthquake?
This event was centered 17 km WSW of Petrolia. Shaking intensity falls off sharply with distance from the epicenter and depends on depth and local geology, so check the USGS "Did You Feel It?" report for this event for real felt-shaking data rather than assuming from magnitude and distance alone.