Residents along the Northern California coast felt mild shaking on Saturday morning after a 3.6 magnitude earthquake struck offshore near Petrolia in Humboldt County. According to the U.S. Geological Survey (USGS), the quake occurred at 9:55 a.m. and was centered about 27 kilometers west of Petrolia, at a depth of roughly 20 kilometers beneath the ocean floor.
Light Tremors, No Damage Reported
The tremor was lightly felt across several communities near Humboldt Bay, including Eureka, Arcata, and Fortuna. So far, there have been no reports of damage or injuries, and at least two residents submitted “Did You Feel It?” reports to the USGS, confirming mild but noticeable shaking.
Emergency officials confirmed that no tsunami warning was issued, as the quake’s size and depth did not pose any coastal flooding threat.
No Impact on Roads or Utilities
Despite the brief shaking, local infrastructure remained unaffected. There were no power outages, utility disruptions, or road closures reported in connection with the earthquake. Authorities continue to monitor the area, but aftershocks — while possible — had not occurred by early Saturday afternoon.
Why This Region Is Prone to Earthquakes
Northern California is one of the most seismically active areas in the U.S., sitting near both the Cascadia Subduction Zone and the Mendocino Triple Junction. This unique geological setting is where three major tectonic plates — the Pacific, North American, and Gorda plates — all meet. While small quakes are common, the region is also capable of producing larger, more dangerous earthquakes, which is why officials continue to promote preparedness.
Earthquake Preparedness Tips for Residents
Though Saturday’s quake was minor, residents are encouraged to stay ready for stronger seismic events. Here are some quick earthquake safety reminders:
Keep an emergency supply kit with food, water, first-aid items, and flashlights
Secure heavy furniture and wall-mounted items
Create a family communication plan in case of emergency
Know safe spots in your home (under sturdy tables or against interior walls)
Practice “Drop, Cover, and Hold On” drills
Earthquake Summary Table:
| Detail | Information |
|---|---|
| Magnitude | 3.6 |
| Location | 27 km west of Petrolia, CA |
| Depth | 20 km |
| Time | 9:55 a.m. local time |
| Affected Areas | Petrolia, Eureka, Arcata, Fortuna |
| Damage or Tsunami | None reported |
| Aftershocks | None confirmed as of early afternoon |
Saturday’s light quake off the coast of Petrolia is a reminder of the region’s active seismic nature, even though no damage or injuries occurred. While small earthquakes like this are typical for Humboldt County and nearby communities, they highlight the importance of staying prepared for stronger events in the future. Residents should review their safety plans and continue to monitor updates from trusted local and national sources.
