Multiple earthquakes have struck California's Bay Area, just miles from the home of the world's biggest tech companies in Silicon Valley.
A magnitude 4.0 tremor struck just 23 miles south of San Jose at 9.16am ET Wednesday morning.
It was quickly followed by a smaller one, of magnitude 2.7, two minutes later, and then a more significant magnitude 3.6 quake at 9.20am.
The quakes struck just miles from the headquarters of firms including Google, Apple, Nvidia, Meta, Netflix and countless startups.
Over 1,200 people near the quake's epicenter, east of Gilroy, reported feeling the seismic event to the US Geological Survey (USGS).
Readings from the area have revealed that shaking from the initial 4.0 quake reached San Francisco, over 60 miles away.
Quakes between 2.5 and 5.4 in magnitude are often felt for several miles in all directions but typically cause only minor damage, such as knocking objects off shelves.
Just two days ago, California's Bay Area was shaken by a series of earthquakes which struck in quick succession just north of San Francisco, raising concern in the seismically active region.
Overall, the shaking on Wednesday morning and on Monday was reported by USGS as being 'weak' or 'light,' and no injuries have been reported.
San Jose Mineta International Airport has also continued to operate normally, according to Flight Aware and the Federal Aviation Administration (FAA).
Roughly one million people live in San Jose, with roughly eight million scattered throughout the entire San Francisco Bay Area in California.
The entire region sits along the infamous San Andreas Fault, an 800-mile plate boundary responsible for much of the state's seismic activity, stretching from Southern California, through the Bay Area, to the northern part of the state.
The magnitude 4.0 quake took place about five miles from the Calaveras Fault, a major branch of the San Andreas in Northern California.
The San Andreas boundary doesn’t work alone. It's connected to a whole family of parallel and branching faults, including the Hayward, Rodgers Creek, and Calaveras, which take some of its plate motion and spread the earthquake risk across the entire region.
The last major earthquake to break out along the Calaveras Fault happened over 40 years ago, when a magnitude 6.2 quake erupted on April 24, 1984.
USGS has warned that the San Andreas Fault could generate a quake even stronger than this, potentially reaching up to 8.2 in magnitude.
Just minutes away from the quake's epicenter sits Silicon Valley, the bustling tech heart of California's Bay Area.
Roughly 1.5 million people work in Silicon Valley's broader economy, with most of the jobs tied directly to the tech sector that fuels its fame and fortunes.
The region's companies crank out hundreds of billions of dollars in annual revenue, a major chunk of California's massive $4 trillion economy, thanks to high-flying profits from software, chips, and cloud services.
Approximately 100 small earthquakes have shaken California's Bay Area this month, prompting scientists to dig into what's driving the unusual burst of activity.
Sarah Minson, a research geophysicist with the US Geological Survey's Earthquake Science Center at California's Moffett Field, told SFGATE: 'This has happened many times before here in the past, and there were no big earthquakes that followed.'
'We think that this place keeps having earthquake swarms due to a lot of fluid-filled cracks, thanks to very complex fault geometry, unlike, say, the San Andreas Fault, which is this nice clean edge.'
