A 4.6 earthquake near Boulder Creek rattled Santa Cruz County early Thursday, sending tremors across the Bay Area and reigniting concerns over seismic safety in California.

Early Morning Shock Rocks Community

The United States Geological Survey (USGS) reported the quake struck at 1:41 a.m. near Boulder Creek at a depth of 6.2 miles. Initially assessed at 4.9 magnitude, the reading was later revised to 4.6 by 3 a.m.

Residents in nearby towns—including San Ramon, Fremont, Burlingame, and Los Gatos—felt strong shaking, while lighter tremors were reported in Oakland, San Francisco, Berkeley, Milpitas, Walnut Creek, Pleasant Hill, San Leandro, Dublin, and Richmond, according to Did You Feel It Responses.

Minimal Damage Reported

Despite the intensity, no major injuries or structural damage were reported. In Boulder Creek, a local pharmacy saw merchandise tumble from shelves, a minor reminder of the quake’s force.

USGS officials warned that aftershocks are likely over the coming days.

Aftershock Forecast

"There will likely be smaller aftershocks within the next week, with up to 9 magnitude 3 or higher aftershocks. Magnitude 3 and higher aftershocks are large enough to be felt nearby," the USGS said.

Forecasters noted a 60% chance of another magnitude 3.0 or higher quake, a 14% chance of a 4.0 magnitude or stronger tremor, and a 2% probability of a magnitude 5 or above aftershock in the next seven days. They emphasized that forecasts are particularly fluid during the first 72 hours after the mainshock.

Safety Tips During an Earthquake

The USGS and ShakeOut advise residents to act immediately when shaking begins:

• Drop, Cover, and Hold On under a sturdy desk or table.
• Move to a hallway or against an interior wall, away from windows and heavy furniture.
• Avoid kitchens, fireplaces, and rushing outdoors.
• If outside, find an open area away from buildings, power lines, and falling debris.

The early-morning tremor is a reminder that California sits on a seismic tinderbox, and preparedness remains crucial as aftershocks may follow the 4.6 earthquake near Boulder Creek.