This USGS Seismologist's Critical Role Explaining Earthquake Science to Californians

On Friday, a magnitude 3.8 earthquake struck an area of mountainous desert near Indio, California, 125 miles east of downtown Los Angeles. Such a quake isn’t unusual for the area. But the epicenter initially seemed awfully close to the infamous San Andreas Fault, which cuts through the vicinity.

While there are plenty of other fault lines in Southern California that could deliver a significant, highly disruptive and damaging seismic event to the highly populated region, this southernmost section of the San Andreas Fault in particular is always worrisome.

The next “Big One” for the San Andreas—many scenarios anticipate something in the range of a magnitude 7.8 event —is expected to start in this part of California, somewhere near the Salton Sea and send damaging seismic waves northwest along the fault into the Los Angeles basin , which will shake like a bowl of jello . Such a quake could kill an estimated 1,800 people , causing more than $200 billion damage and disrupt infrastructure and economic activity for months if not years.

So to anyone interested in earthquakes, new seismic activity near Indio and the Salton Sea can spark immediate interest with one looming question in mind: Does it signal anything for the San Andreas and the possibility that the dreaded Big One for Southern California could be soon on the horizon?

Following Friday’s quake near Indio, U.S. Geological Survey seismologist Lucy Jones , one of the most highly visible earthquake experts in the region who also serves as a science adviser for seismic safety for Los Angeles Mayor Eric Garcetti— took to Twitter , as she often does, to provide some informed observations of the event: “Tonight's M3.8 well east of San Andreas, on north-striking fault.”

Similarly, on May 20, a magnitude 4.0 earthquake near the Salton Sea prompted a question for Jones from a Twitter user : “Any concerns with 4.0 or 4.1 quake at Salton Sea given its proximity to the San Andreas?

Jones’ reply : “Tonight's M4.0 is 23 km south of San Andreas. All CA foreshocks have been within 10km of mainshock so no extra concern.”

A translation for those unfamiliar with Southern California seismology: Relax, the those smaller quakes don’t necessarily portend something more immediately menacing for the San Andreas Fault.

With earthquakes, Jones provides a critically important public information service: She provides sobering, informed assessments of seismic risks and realities and, perhaps more importantly for the world of social media, dispels myths and misinformation that may be circulating online.

And it’s certainly been an interesting week or so for the looming threat of destructive earthquakes in California.

First off, the highly anticipated movie “ San Andreas ,” which features the dramatic destruction of Los Angeles and San Francisco in a series of catastrophic San Andreas earthquake events, was released and was the top-grossing film this weekend .

Last week, Jones livetweeted the movie’s Hollywood premiere , leveraging all the attention on the disaster blockbuster as a teachable event regarding earthquake science in California.

Jones also reviewed the movie for The Hollywood Reporter , again, laying out earthquake facts against the over-the-top plot line:

Nobody should confuse San Andreas with Seismology 101. Hollywood usually exaggerates for effect, and this movie is no exception; both the magnitude of the shaking and the damage displayed are exaggerated beyond reality. Magnitude 9 earthquakes only occur on “subduction zones,” places where tectonic plates collide, pushing one plate under another and deforming the sea floor to create tsunamis. It has been millions of years since there was an active subduction zone under Los Angeles or San Francisco. The modern day San Andreas Fault maxes out at about magnitude 8.3, and, being mostly on land, will never produce a big tsunami.

The level of destruction portrayed in the movie is over-the-top, collapsing high rises with heedless abandon. The gaping chasm we see rupturing the San Andreas in central California belongs to the realm of the completely impossible. If the fault could open up like that, there would be no friction — and without friction there would be no earthquake.

Also last week, social media was buzzing over a Dutch earthquake enthusiast’s prediction of a catastrophic magnitude 8.8 West Coast earthquake that he had said would happen Thursday at 4 p.m. Pacific time, timed with a planetary alignment.

Jones’ take on that : “Anyone who believes that the gravitational pull of Venus has more impact than that of the moon isn't listening to science.”

That predicted earthquake didn’t happen.

Jones has been with the U.S. Geological Survey since 1983 and is also a visiting research associate at the Seismological Laboratory at Caltech. In her role advising Garcetti on earthquake resiliency, Jones is technically independent of Los Angeles City Hall.

She told The Planning Report in 2014 :

Both the USGS and the Mayor’s Office feel it’s important that I do not work for the city. The price of getting me for free is that I’m governed by my scientific integrity, not by political decisions. That gives citizens the confidence that this is based on factual information.

It’s cool that the Mayor’s Office wanted to try and deal with the real issues. I can give them a very long list—longer than anyone can deal with—of things that can go wrong in a big earthquake. They’re trying to grapple with ones that have the biggest consequences, recognizing that the financial demands will need to be traded off with the other needs of the city.

Jones has highlighted the vulnerability of aqueducts that provide water to Los Angeles, which could be severed by the San Andreas Fault during a large earthquake.

"We're the first city that's really bet its life on outside water," Jones said in December, according to the Los Angeles Times . "We have to cross the faults. There's no way to not go over the fault."

In May, Jones applauded the Los Angeles City Council for passing legislation requiring higher seismic standards for cellphone towers so communications can continue following an earthquake.

"Here we said, we want more than life safety, we want cell towers that will continue to function after the earthquake, because our society needs cellular communication," Jones said, according to KABC-TV .

Last month, Jones was recognized as a Samuel J. Heyman Service to America Medals finalist for citizen services—the “Sammies” recognize federal workers “whose work makes our country better, healthier and stronger.”

For all her work to get Southern California prepared for the next seismic disaster and providing scientific expertise in the public policy arena, Jones certainly is a deserving honoree.

“Her objective is not just to deliver science, but to explain to decision-makers and policymakers how they can better handle natural disasters and, in particular, earthquakes,” said Rob Graves, a USGS seismologist, according to Jones’ Sammies finalist profile . “She is not doing science for the sake of science, but actually getting the information into broader use where it will benefit society.”