Earthquake swarm shakes California’s Lake Tahoe: USGS

A swarm of at least two dozen earthquakes measuring up to 3.4 struck beneath California’s Lake Tahoe, the U.S. Geological Survey reports.

According to the USGS, the remaining quakes ranged in magnitude from 0.1 to 3.0.

The hours-long series of quakes, including the 3.4 magnitude quake, began around 8 a.m. Saturday, July 20, the USGS reported. More followed, with the most recent at 6:19 a.m. Sunday, July 21.

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The magnitude 3.4 quake, with a depth of 6.5 kilometers, struck at 8:02 p.m. Saturday, the USGS said.

More than 100 people, from as far away as Placerville and West Sacramento, reported to the agency that they felt the tremors.

What you need to know about earthquakes

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

Earthquakes with a magnitude of 2.5 to 5.4 are often felt, but rarely cause much damage, according to Michigan Tech. Earthquakes with a magnitude of less than 2.5 are rarely felt by most people.

The sudden, rapid shaking of earthquakes can trigger fires, tsunamis, landslides or avalanches. They can happen anywhere, but are most common in Alaska, California, Hawaii, Oregon, Puerto Rico and Washington, according to the Department of Homeland Security.

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

• When you are in a car: Pull over and stop. Apply your handbrake.

• When you are in bed: Turn face down and cover your head with a pillow.

• When you are outside: Stay away from buildings. Do not enter.

• Once you are inside: Stay and don’t run outside. Stay away from doorways.

Officials say the best way to protect yourself during an earthquake is to lie down, take cover and hold on.

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

Make 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.

If you’re under a table, authorities say you should hold one hand and be ready to move it.

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