San Andreas ‘Big One’: Overdue California Earthquake Will Be Worse Than Expected, Two Faultlines To Erupt At Same Time

The San Andreas fault is overdue for massive earthquake that researchers believe will cause extensive devastation in Southern California. However, a new study suggests that the devastation will be even greater than originally anticipated, as it is likely that not one but two major faults will erupt at the exact same time. In addition to the San Andreas faultline, geophysicists believe the San Jacinto fault will rupture at the exact same time. This will cause even more damage than was anticipated with “the Big One,” as more densely populated areas lie along the San Jacinto fault.

The Daily Mail reports that Southern California is long overdue for a devastating earthquake along the San Andreas fault. The last major eruption on the San Andreas fault was in 1812 over 200 years ago. However, the U.S. Geological Survey notes that the faultline typically has a major earthquake every 150 years. Therefore, the San Andreas fault is 54 years overdue for a big one. The Smithsonian notes that when the San Andreas fault actually ruptures, it is expected to create widespread damage. The general consensus is that it will cause roughly $200 billion in damages and make life in Southern California after the quake miserable.

“Such a quake would cause some $200 billion in damage, 50,000 injuries and 2,000 deaths, the researchers estimated. But it’s not so much about dying in the earthquake. It’s about being miserable after the earthquake and people giving up on Southern California.”

Though the devastation will be great, it won’t look like scenes from the San Andreas movie where the Golden Gate Bridge is swept away in a tsunami, but instead will be chaos resulting from a lack of fresh water, electricity, and damaged roads.

While geologists have long been concerned about the devastation from a large San Andreas faultline earthquake, new studies suggest the situation may be even more dire than previously thought. Instead of just roughly 50,000 injuries and $200 billion in damages, if the San Jacinto fault erupts with the San Andreas, the numbers would skyrocket as the fault lies in more densely populated areas such as San Bernardino, Riverside, and San Diego.

The new study was performed by the assistant professor of Geological Sciences at the University of California in Riverside Julian C. Lozos. The professor has researched the San Andreas earthquake of 1812 and learned that the faultline was not the only one that erupted that day. Lozos says that evidence suggests that the two faultlines erupted simultaneously in 1812 with San Jacinto. The professor says computer models showing the quake starting further south than previously thought on the San Jacinto fault before “jumping” over to the San Andreas.

“If there’s a joint rupture it will create a larger earthquake, especially if it starts on the San Jacinto. Say you’re stressed out and you snap. You might then stress out your friend too. That’s that same way faults work. They stress each other out.”

Lozos says that the best way to predict future earthquakes is to look at “big ones” from the past and that the models are showing that it is highly likely that when the big one hits Southern California, it will be a double whammy with both the San Andreas and San Jacinto faults erupting at the exact same time.

“Looking at old earthquakes in general is really a good way to figure out what faults are capable of doing.”

With the new model suggesting that a double “Big One” could hit Southern California at any given moment, Lozos says more preparations need to be made as the region is not prepared for a joint rupture of this magnitude.

“In southern California, much of our infrastructure was built to withstand a rupture of either the San Andreas or San Jacinto faults, but not both at the same time.

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