3.8 Magnitude Earthquake Rattles San Francisco and the East Bay

A series of earthquakes struck the Bay Area on Thursday morning.

The first and largest hit at 8:30 a.m., centered about 2.4 miles north of San Leandro, according to the U.S. Geological Survey. The agency initially put it at magnitude 4.1, then revised it down to 3.9 and later to 3.8.

Residents reported feeling strong shaking in the East Bay, with rumblings across the water into San Francisco, according to social media posts on Reddit. 

Related Article

Two smaller quakes followed at 9:07 a.m., four seconds apart. The USGS recorded one at magnitude 3.0 and a second at 2.8, also centered about 2 miles north of San Leandro.

There were no immediate reports of damage or injuries.

BART slowed service systemwide. The agency said trains were running at reduced speeds while crews completed safety track inspections and told riders to expect residual delays of up to 20 minutes.

The Hayward Fault runs through the area, from San Pablo Bay south to Fremont. The USGS said the initial quake was strong enough to trigger ShakeAlert, the West Coast early warning system, which issued its first message 3.7 seconds after the quake began. 

No wireless emergency alerts went out to phones because the system only sends those when a quake is estimated at magnitude 5.0 or higher.