Reno hasn’t had a 6.0 quake in 110 years

The danger of a “big one” is everpresent in earthquake country.

Nevada is the third most seismically active state in the U.S. behind just California and Alaska, according to the National Parks Service. The state is striped with fault lines, and earthquakes of 7.0 magnitude and above have been recorded across Nevada throughout its history.

How at risk are we, and what is being done to help minimize the damage?

The RGJ talked with Kyren Bogolub, a network seismologist with the Nevada Seismological Laboratory at the University of Nevada about whether the recent string of earthquakes in south Reno is cause for concern.

What causes earthquakes?

Earth’s crust is made up of a series of tectonic plates that are in constant motion. When movement between these plates occurs suddenly, it can cause earthquakes. The places where these large plates meet can cause severe earthquakes, including the West Coast, where the North American Plate and the Pacific Plate meet.

But powerful earthquakes also can occur in intraplate fault zones, sometimes far from where tectonic plates meet.

“We’re not on a plate boundary here in Nevada,” Bogolub explained. “But what we do have is active faults — kind of a fancy word of saying ‘a crack in the rock.’

“When you have rock moving against other rock, that’s going to create earthquakes. We describe it as the stick-slip motion. If you have a bunch of pressure building up on two sides of a fault, it’s going to stick together because of friction. But if that pressure is high enough to overcome the friction, you have this sort of snap, and that is the earthquake.”

Are we due for a ‘big one’ here?

Significant earthquakes were frequent in Reno’s early days. In a 55-year stretch from 1860 to 1914, seven quakes measuring 6.0 and above struck Reno, Virginia City and Carson City. One quake on Dec. 10, 1900 caused the hot springs and geysers at Steamboat Springs to dry up.

East of Reno, Churchill County suffered six earthquakes 6.0 or greater in a five-year stretch in the 1950s; the results of a powerful 7.2 quake in December 1954 are still visible in the landscape near Fallon nearly 70 years later.

But in the past six-plus decades, northwestern Nevada hasn’t seen any earthquake greater than 6.0. The Mogul-Somersett earthquake swarm in 2008 topped out at just 4.7, and the Galena earthquake swarm in 2018 only reached 2.7.

That doesn’t mean we’re overdue for a big one, Bogolub explained.

“It’s really hard to say ‘overdue’ in geologic time,” she told the RGJ. “The recurrence intervals for earthquakes can be on the scale of hundreds to thousands of years. It could be off by a few thousand years, but I wouldn’t say we’re overdue. I would just say that we live in earthquake country and a largemagnitude earthquake could happen.”

The recent string of earthquakes in the Virginia Foothills doesn’t necessarily indicate that there’s anything more significant on the way, Bogolub said.

Seismological Lab hopes to roll out early-warning system soon

While seismologists remain unable to predict earthquakes, three earthquake-prone states on the West Coast — namely, California, Oregon and Washington — participate in the U.S. Geological Survey’s ShakeAlert system.

The system identifies early signs of earthquakes and is able to alert that a quake is seconds away. Residents receive text messages to take immediate cover, and institutions including transit systems, hospitals and first-responder stations could take immediate action to reduce the earthquake’s immediate impacts.

But while Nevada-based monitoring stations contribute to the predictions, Nevada doesn’t have its own alert system in place.

“California has earthquake early warning, but Nevada doesn’t,” Bogolub said. “It’s a little bit unfortunate because if there was a big earthquake — in Tahoe, for example — people on the California side of the border would get an alert, and people in Nevada wouldn’t. That’s a big thing that we really want to address soon.”

For a statewide system to roll out, seismologists would need to identify locations for expanding the state’s network of monitoring stations. How to pay for the infrastructure remains to be seen, however. Bogolub said she hopes for state and federal funding to implement the program.

The good news? The three coastal states already have done the heavy lifting.

“It’s not like we have to invent that system,” Bogolub said. “The barrier is not as high as it was for some of the earlier states that adopted (early warning), but it does take a bit of planning and resources. So I don’t think it’s going to happen this year — maybe in the next five years.”