Drop and Cover

Yes. And as soon as UUSS director Keith Koper realized that, he dove under his desk to ride out the shaking. “My cat came flying by,” he says. “She was looking at me like it was my fault.”

He then called associate director Kris Pankow and set into motion plans that their team had practiced many times—with some modifications for the COVID-19 pandemic. Just two days before, the staff had started working remotely.

Koper drove to campus to speak to the media and coordinate with state and university leaders. “And when I got there, there was actually a news crew waiting at the door for me to get in,” he adds.

Since 1966, UUSS has been the go-to source for earthquake information in Utah and beyond. The network of stations, now numbering more than 200 and with locations around the state and Yellowstone region, relays information in real time, providing the building blocks for earthquake data reporting and maps of ground shaking within minutes of a quake.

That reputation drew the media crews to the U, where the first news conference of the day began via Zoom with Koper and Bob Carey, earthquake program manager for the Utah Department of Public Safety, answering reporters’ questions.

Hold your horses. That news didn’t come through official channels. Even during the news conference, rumors began flying on social media. One claimed that the U was predicting a 9.0 earthquake within “the next two hours.” Another claimed that Utah’s oil refineries were out of commission, leading people to stock up on fuel.

Part of the confusion came from misunderstandings about how seismology works and how earthquakes happen. Quakes can’t be predicted, says Pankow. And the Wasatch Fault simply isn’t big enough to produce enough energy for a magnitude 9.0 quake. The strongest we could see is around a magnitude 7.0 to 7.3—still plenty large enough that it’s what some call “The Big One.”

Here’s how earthquakes happen: If you pull something elastic, like a rubber band, it will stretch, but only to a point. When you stretch it too far, small cracks begin to form and—snap!—the band breaks with a jerk.

It’s that sudden release of energy that causes an earthquake, says Pankow. “Roughly eight to 10 kilometers [five to six miles] below the earth, there was a patch of area on this fault plane all along this crack where the stress exceeded the strength. When you’ve built up enough strain on the fault, those patches break.”

Yeah, all the way in Magna, about 14 miles west of Salt Lake. That’s where Danny Colosimo BS’79 lives. He’s the co-owner of Colosimo’s Standard Market, on the city’s Main Street. He was a child in the 1962 quake, also centered in Magna. But the 2020 quake, he says, felt much more violent. “This felt like you were sinking,” he says, “or somebody had just grabbed and pushed on the house.”

Soon after checking on his neighbors, he drove down to Main Street to check on the store. He saw the damage as soon as he arrived. “And that’s when my heart sank,” he says. The bricks from an upper portion of the side wall had crashed to the sidewalk. Still, Colosimo was grateful. A food delivery had been scheduled for later that morning. “Had I been there I could have been crushed.”

Colosimo was surprised that the quake occurred on the Wasatch Fault, which comes to the surface at the base of the Wasatch Mountains, on the east side of the Salt Lake Valley. Magna is on the west side, at the base of the Oquirrh Mountains.

“We all hear about the Wasatch Fault,” Colosimo says. “You know, that’s a big, well-known fault. I had no idea that Magna was on it.”

Well, fault planes aren’t always straight lines plunging into the earth. The Wasatch Fault bends as it gets deeper and flattens out. It underlies the entire valley.

One of many. As of June 24, UUSS had recorded 2,320 aftershocks in what’s now being called the “Magna sequence” of earthquakes. Pankow has another analogy to talk about aftershocks. Picture two wooden boards, she says, both covered in sandpaper. Now try to slide them past each other. “You have a lot of friction,” she says. “It doesn’t just slide smoothly, right? It sort of jumps.” All of those jumps are part of a sequence of earthquakes, as a fault tries to settle back to rest. For very large earthquakes, aftershocks may continue for years—or decades.

“It’s re-equilibrating,” Pankow says. “And it’s just getting to where it’s locked back together. All of those aftershocks are the earth sort of recovering from that big pull.”

In a sequence, the largest event is called the “mainshock.” Any that come before are called foreshocks, and any that follow are called aftershocks. In the Magna sequence, the mainshock was the very first. So when is a sequence over? Generally when seismic activity has settled down to background levels, Pankow says.

Aftershocks are a scientific opportunity. Because the risk of aftershocks decreases with time, U geoscientist Amir Allam jumped right into action on the day of the first quake to gather what data he could.

Allam had felt his fair share of quakes living in Southern California and Alaska. So when he woke up to his house shaking, he immediately started counting. Earthquakes consist of several types of seismic waves, and the time difference between them, he says, can give you an idea of how far away the quake was. It’s like counting the time between a flash of lightning and a clap of thunder.

“Then once I realized it was close by,” he says, “I jumped up and said, Okay, it’s time to go to work. And I rushed into the office to get my sensors ready.”

Geoscientists can learn a lot about the subsurface with every quake and aftershock. The pulses of energy that ripple through the layers of rock reveal faults and other features in the Earth, similar to the way a CT scan uses X-ray pulses to reveal features inside the body.

Allam and his colleagues began placing portable seismometers, each a little smaller than a coffee can, to record seismic events. Their first stop was a landfill near the epicenter. “It was just the foulest smell,” he says. “It’s the nastiest field work I’ve ever done, digging in mucky mud.” Next, they went to the construction site of a new Utah State Prison.

That’s a normal feeling, says Michelle Ertl, a psychologist at the Utah Center for Evidence Based Treatment. “Being more aware, being more on guard, all of that is completely normal and typical,” she says.

Any traumatic event sets our brains into a state of hyper-alert, says Ertl, who helped clients work through earthquake-related anxieties. Heightened awareness helps us stay prepared in case additional threats emerge. Re-regulating can take weeks. And repeated aftershocks aren’t helpful. “When there’s this consistent reactivation, it can take a little bit longer for that re-regulation to happen.

Up until mid-March, Utahns had been shopping and attending school, church, and sporting events as usual. But COVID-19-related closures rolled out through that week, sweeping nearly all of those activities out of daily life. Which is just when the ground started shaking. Repeatedly.

“A lot of people had stress levels that were already high,” Ertl notes. Physical distancing measures also meant that people didn’t have access to some of the social support they would normally lean on to cope, she says.

So emotional preparedness is a thing, too, just like storing water and food. Learn how you best manage stress and anxiety, Ertl says, and maybe include in your emergency kit some kind of game or distraction for when the event is over, to reassure your brain that things are safe.

“Your body is doing what it’s designed to do to keep you safe,” she says. “The majority of people will recover on their own over time.”

Yes, things could have been much worse. Welcome to Bob Carey’s world. At the Utah Earthquake Program, he and his team run simulations to prepare for various earthquake scenarios. For this quake, he says, some things were much less complicated. Many parents were working remotely, and schools had already been closed. Utah’s hospitals were prepared for a surge of patients.

Out of simulations (as well as moderate quakes such as this one) arise recommendations and plans to minimize damage and accelerate recovery. The vulnerability that many felt, he says, can become a constructive tool to help prepare for future emergencies.

“You’re used to turning the light on,” he says. “You’re used to turning on the faucet, and you just don’t think twice about that. When people start to feel vulnerable, that’s when they actually start to do things.”

Carey, Pankow, and others who pay acute attention to Utah’s seismic hazards see an opportunity. The risk of a large earthquake on the Wasatch Fault is suddenly more real.

“When I do outreach talks, people say, ‘You’ve been telling me for 20 years that there’s going to be an earthquake, and I still haven’t felt one. You need to change your story,’ ” says Pankow. “Right. And now we’ve had that event.”

About the author: Paul Gabrielsen is a research and science writer for University Marketing & Communications.