Small magnitude 3.4 earthquake hits near Antioch, Contra Costa County, California, USA

A shallow magnitude 3.4 earthquake was reported after midnight near Antioch, Contra Costa County, California, USA.
According to the United States Geological Survey, the quake struck on Saturday, September 12th, 2026, at 12:25 am local time, at a shallow depth of 11 miles. Shallow earthquakes are felt more strongly than deeper ones because they are closer to the surface. The exact magnitude, epicenter, and depth of the quake might be revised within the next few hours or minutes as seismologists review the data and refine their calculations, or as other agencies issue their reports.
Our monitoring service identified a second report from the European-Mediterranean Seismological Centre (EMSC), which listed the quake at magnitude 3.1.
Weak shaking might have been felt in Blackhawk (pop. 9,400), located 7 miles from the epicenter; Brentwood (pop. 59,000), 7 miles away; Antioch (pop. 110,500), 9 miles away; San Ramon (pop. 76,100), 12 miles away; and Pittsburg (pop. 69,400), 12 miles away.
Other towns or cities near the epicenter where the quake might have been felt as very weak shaking include Livermore (pop. 88,100), located 13 miles from the epicenter, and Concord (pop. 128,700), 15 miles away. In San Francisco (pop. 827,500, 34 miles away), San Jose (pop. 997,400, 37 miles away), and Sacramento (pop. 524,900, 52 miles away), the quake was probably not felt.

Earthquake data:
Date & time: Sep 12, 2026 12:25 am (GMT -7) local time (12 Sep 2026 07:25 GMT)
Magnitude: 3.4
Hypocenter depth: 17.89 km
Epicenter coordinates: 37.87°N / 121.8°W (Contra Costa County, California, United States)
Primary data source: USGS
https://www.volcanodiscovery.com/earthquakes/news/350880/Small-magnitude-34-earthquake-hits-near-Antioch-Contra-Costa-County-California-USA.html