M 3.5 Minor Earthquake Recorded Near Johannesburg, California

Source: USGS · Southern California

Areazine synthesizes this USGS earthquake report directly from USGS's official public data feed. See our methodology for full source attribution and refresh cadence.

A magnitude 3.5 earthquake occurred Monday afternoon approximately 18 km east-southeast of Johannesburg, California, at a shallow depth of 3.3 kilometers.

What this USGS earthquake report tells you, and what most readers miss

This notice was issued by USGS on April 6, 2026 and geographically references Southern California. Its severity classification of "low" signals how the issuing agency weighs the risk of harm if no action is taken - "critical" and "high" tier alerts typically carry direct consumer actions, while "medium" and "low" tend toward informational guidance or monitoring advisories. The category it belongs to - Earthquakes - determines the monitoring protocol behind it, which shapes what follow-up action (checking for structural damage, watching for aftershocks, reviewing local building codes) is relevant and which agency holds authority over the assessment.

Most readers skim a notice like this, check whether they are personally affected, and move on. The more useful lens is to verify its scope, source, and timestamp, then compare related notices without assuming that one record proves a broader trend.

Areazine pairs this record with the original agency URL so you can check the primary source before acting. Its related labels are earthquake, seismic, usgs, California.

What Happened

A minor earthquake with a magnitude of 3.5 ml occurred on February 17, 2026, at 00:20:52 UTC (4:20 PM local time on February 16). The event was centered 18 km east-southeast of Johannesburg, California, and originated at a shallow depth of 3.3 kilometers.

Location Details

The earthquake's epicenter was located at coordinates 35.305°N, 117.457°W. This position is approximately 11 miles east-southeast of the community of Johannesburg. The recorded depth of 3.3 km is considered very shallow; earthquakes occurring less than 20 km below the surface are often more easily felt by those in the immediate vicinity than deeper events of the same magnitude.

Impact Assessment

According to data from the USGS, the maximum instrumental intensity (MMI) was recorded at 4.008, which corresponds to light shaking. There was no tsunami advisory, watch, or warning issued in connection with this event. No specific alert level color was assigned, and there are currently no official reports of damage or injuries associated with this seismic activity.

What You Should Know

Earthquakes with magnitudes between 2.5 and 3.9 are classified as minor. While these events are often felt by people near the epicenter, they rarely cause structural damage. Residents in the region should be aware that aftershocks are a common occurrence following seismic activity, though they are typically smaller than the initial event.

Source

Information provided by the USGS Earthquake Hazards Program.

Original source: USGS Official Notice ↗

All Earthquakes →

Frequently Asked Questions

Common questions about this USGS earthquake report.

What is this USGS earthquake report about?
A magnitude 3.5 earthquake occurred Monday afternoon approximately 18 km east-southeast of Johannesburg, California, at a shallow depth of 3.3 kilometers.
Which agency issued this alert?
This alert was issued by USGS. The original notice is available at the source link at the bottom of this article.
How severe is this alert?
This alert is classified as "low" severity. No immediate action required, but stay aware.
What area is affected?
This alert affects Southern California. Check with USGS for the most current geographic scope.
Where can I find more Earthquakes updates?
Browse the full Earthquakes feed on Areazine at areazine.com/earthquakes/ for the latest updates from USGS and other agencies.