3.4-magnitude quake hits just west of San Francisco Zoo

A 3.4-magnitude earthquake was centered offshore of San Francisco, the U.S. Geological Survey reported.

The slightly more than 6-mile deep quake hit about 3 miles west of the San Francisco Zoo at 1:32 p.m. on Friday, according to USGS.

More than 2,400 people from as far away as Petaluma and Redwood City reported feeling the tremor to the agency.

“San Francisco, we're shaking! I even felt that earthquake here on top of the Bernal Heights hill,” one user on X, formerly known as Twitter, said.

Other users on X described the quake as a “nice little jolt.”

A 4.9-magnitude earthquake also shook near the coastline earlier in the day, McClatchy News reported.

What to know about earthquakes

Magnitude measures the energy released at the source of the earthquake, the U.S. Geological Survey said. It replaces the Richter scale.

Quakes between 2.5 and 5.4 magnitude are often felt but rarely cause much damage, according to Michigan Tech. Quakes less than 2.5 magnitude are seldom felt by most people.

Earthquakes' sudden, rapid shaking can cause fires, tsunamis, landslides or avalanches. They can happen anywhere, but they're most common in Alaska, California, Hawaii, Oregon, Puerto Rico and Washington,

according to the Department of Homeland Security.

If an earthquake strikes, it's best to protect yourself right away. Here are tips from experts:

• If you're in a car, pull over and stop. Set your parking brake.

• If you're in bed, turn face-down and cover your head with a pillow.

• If you're outdoors, stay away from buildings. Don't go inside.

• If you're inside, stay and don't run outdoors. Stay away from doorways.

The best way to protect yourself during an earthquake is to drop, cover and hold on, officials say.

“Wherever you are, drop down to your hands and knees and hold onto something sturdy,” officials say. “If you're using a wheelchair or walker with a seat, make sure your wheels are locked and remain seated until the shaking stops.”

Be sure to cover your head and neck with your arms and crawl under a sturdy table if possible. If no shelter is available, crawl to an interior wall away from windows.

Once under a table, officials say you should hold on with one hand and be ready to move with it.

“There can be serious hazards after an earthquake, such as damage to the building, leaking gas and water lines, or downed power lines,” officials say. “Expect aftershocks to follow the main shock of an earthquake. Be ready to drop, cover and hold on if you feel an aftershock.”