Earthquakes In California: Swarm Has Experts Predicting The Next ‘Big One’

A recent swarm of earthquakes along the San Andreas Fault in California has some experts thinking about what will happen when the “Big One” eventually hits. After seismologists recorded a 4.6-magnitude quake near Gonzales on Monday morning, nearly 30 aftershocks followed.

Per a report from, the first earthquake hit at approximately 11:30 a.m. Residents in San Francisco, nearly 90 miles away from the quake’s epicenter, felt the shaking. Aftershocks ranging from 0.8-magnitude to 2.8-magnitude continued throughout the day.

Geophysicist Jessica Turner, with the U.S. Geological Survey (USGS), said the 30 aftershocks occurred within two miles of where the initial tremor struck. However, even though the number of quakes may seem alarming, she said these are actually quite characteristic of this type of seismic event.

“Usually the larger magnitudes that are shallow in depth, that happen really close to the surface —those usually have more aftershocks. And this one was only six kilometers (four miles) beneath the surface, so it’s very shallow.”

Turner’s view is relatively optimistic and suggests the recent earthquake swarm is no cause for alarm. Yet, another member of the USGS has made some stimulating projections predicting the devastation of an impending large earthquake in California.

“When you live here in Southern California you just have to say it will happen,” said seismologist Lucy Jones, as reported by CBS Los Angeles. “When we have a big San Andreas earthquake it’ll be felt in Las Vegas and in Arizona. It may be felt in the Bay Area.”

Massive earthquake in California would devastate the area.
Computer models project a large California earthquake would significantly damage buildings and put thousands of lives at risk. [Image by Justin Sullivan/Getty Images]

Computer models forecast a 7.8-magnitude tremor striking within the San Andreas Fault would cause massive destruction. In the scenario, damage estimates reach over $200 billion, with 300,000 buildings destroyed or significantly damaged and 1,800 people dead.

An earthquake of this magnitude in California would render roads, utility lines, sewer systems, and railways unusable, noted Jones. The collapse of “vulnerable” infrastructure would leave the state helpless and cut off from the rest of the world.

Chris Ipsen, with the Los Angeles Emergency Management Department, said the agency is preparing for a “worst case scenario” if the Big One hits California. Likely taking at least 18 months following such a large disaster, getting the water systems and electrical grid back online would be a major concern of the department.

As far as a tsunami after the quake, Ipsen said that isn’t one to worry over. To create a massive tidal wave, the earthquake would need to occur underwater, and California does not have any fault lines offshore.

Residents need to get ready for next California earthquake.
Experts encourage people to be prepared for the next large earthquake in California. [Image by ]

While the California earthquake swarm has some thinking about the Big One, experts cannot say for sure when or where it will occur. However, they do concur that a devastating quake “is inevitable,” most likely along the San Andreas. For now, experts stress local residents and governments need to make preparations to keep the loss of life and property below the computer model expectations.

[Featured Image by Justin Sullivan/Getty Images]