A cluster of small earthquakes shook parts of the San Francisco Bay Area early Monday, hours after the Seattle Seahawks arrived in the region to begin Super Bowl week preparations, according to the Associated Press and the U.S. Geological Survey.
The strongest of the quakes was a magnitude 4.2 that struck shortly after 7 a.m. just south of San Ramon, according to the U.S. Geological Survey.
At least a dozen smaller earthquakes followed, beginning around 6:30 a.m. and continuing for more than an hour in the same area.
There were no immediate reports of major damage.
Bay Area Rapid Transit said some delays were possible as trains briefly ran at reduced speeds during routine track safety inspections.
Shaking was felt more than 30 miles away in San Francisco and across East Bay cities including Oakland and Richmond.
San Ramon and surrounding parts of Contra Costa County have experienced frequent seismic activity in recent months.
The area recorded 87 earthquakes of magnitude 2 or higher in November and December, according to a San Francisco Chronicle analysis of USGS data.
Seismology experts say the region has a history of earthquake swarms, in which repeated quakes strike a small area without following a typical mainshock-aftershock pattern.
The timing of Monday’s shaking coincided with the arrival of the Seattle Seahawks, who touched down in San Jose on Sunday evening to begin their week in the Bay Area ahead of Super Bowl LX.
The team is staying in the region as it prepares to face the New England Patriots on Sunday at Levi’s Stadium.
Seattle coach Mike Macdonald acknowledged the unique demands of Super Bowl week, which includes Opening Night media events on Monday and additional obligations throughout the week.
“The days will look a little bit different,” Macdonald said. “It’s really the intent behind what we’re trying to do every day. Just staying focused on the things that we can control, because there is so much extra.”
Veteran receiver Cooper Kupp, who previously played in a Super Bowl, said the key is staying present amid the distractions.
“If you’re where your feet are—you handle what today is,” Kupp said. “Any time you get to do this, it is one of the pinnacles of your life.”
While there is no connection between the earthquakes and the Seahawks’ arrival beyond timing, both added an early jolt to a Bay Area Monday already set to be busy with Super Bowl events.