A 4.1-magnitude earthquake struck Wednesday morning in Sacramento County, according to preliminary data from the U.S. Geological Survey. The quake, which struck at 9:29 a.m., was centered near Isleton, the agency’s website showed.

“It felt like an 18-wheeler ran into the building,” Devery Stockon, manager of the Owl Harbor Marina in Isleton, said Wednesday morning. Stockton said the earthquake shook the marina’s office for about a minute, but did not appear to cause any lasting damage to the facility, which is built on stilts near an inlet of the San Joaquin River.

The area is less than a mile south of the earthquake’s epicenter, which was on Brannan Island in the maze of waterways through the Sacramento-San Joaquin Delta, according to USGS. Californians reported feeling light shakes as far south as Stockton and as far north as Sacramento, according to the USGS’s crowd-sourced intensity map.


Initial alerts indicated a higher-magnitude quake had struck, but swift revisions by the USGS downgraded the temblor to a 4.1.

By late Wednesday morning the USGS community “Did You Feel It” map received nearly 3,000 reports that the earthquake had been felt widely across the Sacramento region and the Bay Area, most rating the intensity as weak to light except in the Isleton area, where it was moderate to strong.

Some Bay Area BART trains were briefly halted as a result of the quake but quickly resumed. The quake could be felt in parts of the Bay Area, including San Ramon and downtown Brentwood.