California was rattled by a 5.1 magnitude earthquake recorded near San Jose. An expert said the California earthquake today was Bay Area's strongest tremor since 2014 that hit Napa at 6.0 magnitude.

According to ABC News, Santa Clara County's Fire Department has not received any calls for service. Meanwhile, Santa Cruz County officials said the shaking did not damage any schools, and classes have resumed.

According to retired U.S. Geological Survey seismologist Lucy Jones, it was the biggest earthquake to hit the Bay Area in 15 years. It was followed by aftershocks measuring 3.1 and 2.2; she told NBC Bay Area.  

Despite widespread shaking observed in a region home to almost 5 million people, no casualties or substantial damage were reported.

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ShakeAlert Message Received by Tens of Thousands of People Seconds Before the California Earthquake

The earthquake center was found 12 miles east of San Jose, the biggest city in the Bay Area. The USGS said it happened at 11:42 a.m. and was thought to be 4 miles deep.

Officials from the California Office of Emergency Management and the USGS said about 95,000 individuals who registered for an earthquake warning system got a ShakeAlert message. Most of them got it on their phones just seconds before the ground started shaking, NBC News noted.

Officials stated this number is how many alerts wireless companies have logged for their customers on Tuesday. Robert de Groot, in charge of outreach for USGS ShakeAlert, said that the number is likely to increase sharply as more providers join in.

"People had several seconds of alert time before shaking began at some locations," he said.

Videos of Earthquakes Posted on Social Media

According to USGS seismologist Annemarie Baltay, the epicentre's location was along the Calaveras Fault. Baltay said the shaking was "widely felt," and as of 1 p.m., over 18,000 "did you feel it?" reports had been sent in.

These reports came from Sonoma County, Sacramento, and Central California, among other places.

"Ground shaking appears to have been slightly less than our models expected for this magnitude earthquake," Baltay said.

Meanwhile, many people have posted earthquake videos on their social media accounts.

According to Baltay, there is a one-in-100 probability that an aftershock with a magnitude greater than 5.0 will occur within the next day.

Over the following week, there could be 10 to 15 aftershocks with a magnitude of at least 3.0, NBC Bay Area reported.

"Aftershocks of this magnitude and duration are totally normal for an event of this type," Baltay said.

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This article is owned by Latin Post.

Written by: Bert Hoover

WATCH: 5.1 California earthquake - Seismologist says aftershocks as strong as 4.0 possible - From ABC7 News Bay Area