A series of recent earthquakes in Nevada have provided a shocking reminder of the state’s seismic risk.
It started with a scary earthquake near Reno, followed by an even more destabilizing aftershock near Las Vegas. Neither earthquake caused significant damage, but it has forced Nevadans to talk about the larger geological forces that caused it.
Although California is known for its seismic activity, experts say the danger doesn’t stop at the state line. According to Christy Rowe, director of the Nevada Seismic Laboratory, there are several fault systems that cross the California-Nevada border, and one area that scientists are concerned about is the Lake Tahoe Basin.
“There are some big holes down there under the lake,” he said. “They have had very large earthquakes in the past.”
The largest earthquake to hit the Silver State in recent days occurred at 1:17 a.m. Friday, with a magnitude of 5.2, about 40 miles east of Reno. Just two days earlier, a magnitude 4.4 rumble struck the desert about 60 miles north of Sin City, where some people reported mild shaking.
The area east of Reno also experienced a spate of seismic activity in early April. According to media reports, the most powerful earthquake of that series was a magnitude 5.7 quake 45 miles east of the city, which was powerful enough to cause moderate to strong tremors and knock items off shelves and shelves in the small town of Silver Springs. There were no reports of any significant injuries or damage from the earthquake that struck on April 13.
The spate of earthquakes is a reminder that earthquakes are indeed a threat to Nevada – less profound than the seismic threat in California, sure, but every bit as real.
Perhaps less known is that Las Vegas is surrounded by faults on all sides, which may be surprising since there have been no damaging earthquakes in the city’s short modern history.
But if, and when, someone attacks, the consequences can be serious. A hypothetical magnitude 7 earthquake near Las Vegas could cause about $21 billion in damage by damaging vulnerable buildings and infrastructure. According To the Nevada Bureau of Mines and Geology.
Incline Village – a town on the northeastern shore of Lake Tahoe – “When they found out they were on the Incline Fault, which has produced a magnitude 7 in geologic history, they closed down a school,” Rowe said.
Earthquakes so strong occur every few thousand years in the Tahoe Basin, scientists say. An earthquake of that intensity could also create the threat of tsunami-like waves on the lake, which could exceed 30 feet in height – capable of flooding many areas near the shoreline.
The last major earthquake on the West Tahoe Fault along the western shore of Lake Tahoe is capable of a magnitude 7.1 to 7.4 earthquake. The last major earthquake there occurred about 4,000 years ago.
Quakes are also capable of producing landslide In the Tahoe Basin. A landslide that occurred about 50,000 years ago could have caused waves as high as 100 feet.
The danger of earthquakes due to landslides in lake areas is not just theoretical. A magnitude 7.2 earthquake centered in Montana near Yellowstone National Park in 1959 was the largest earthquake-induced landslide on record in North America. Of the 28 people killed, 26 died after a landslide buried an overflow camping area, according to US Geological Survey.
For Las Vegas, the fault systems that Rowe is particularly concerned about west of the city include the Death Valley fault system and faults in neighboring valleys.
“We know that those faults have produced magnitude 7s,” Rowe said.
The Death Valley Fault System is about 95 miles from Las Vegas. Another, the Hurricane Fault system, is about 75 miles away, “in the northern corner of Arizona and all the way to Utah,” according to Rowe.
The latter “is a huge mistake but has been quite quiet lately,” she said.
He added, “And then there are some loopholes in Las Vegas itself, but not a lot is known about them.” Part of the problem is that many of the microscopic ground structures that scientists need to study to uncover evidence of past earthquakes have already been formed.
Nevada lacks a key seismic safety tool that California, Oregon and Washington have — the earthquake early warning system operated by the USGS, which sends alerts to smartphones or computers before shaking begins.
Congress has allocated funds to the USGS to implement that system in Nevada, but more money is needed to build out the system in that state. Rowe said budgetary cuts and a hiring freeze for the USGS have made efforts to expand the earthquake early warning system challenging.
“How do you expand a program to a larger area when the agency running it is understaffed?” Rowe said.
In particular, Nevada’s seismic sensors are available to help warn Californians that a major earthquake has begun in Las Vegas and that the coming aftershock is just seconds away.
“The irony is that if we had an earthquake in the Las Vegas area, it would send a warning message to Californians who would be affected,” Rowe said. “But in Nevada, we won’t be sent warnings.”
Among Nevada’s vulnerabilities are unreinforced brick buildings, and these may number in the thousands across the state. Brick buildings are one of the deadliest types of structures in an earthquake, as walls falling outward can kill people walking on the sidewalk and even crush cars and buses with deadly force.
A partially collapsed brick building crushes cars in San Francisco during the magnitude 6.9 Loma Prieta earthquake. Five people died when the wall of the fourth floor of a brick building collapsed on the parking lot below.
(CE Meyer/US Geological Survey)
According to Rowe, the community of Silver Springs, which was recently hit by an earthquake, is built on an old lake bed, which amplifies earthquake shaking, and there are a lot of mobile homes there.
According to California earthquake experts, in general, mobile homes are two to five times more vulnerable in an earthquake than wood-frame homes.
“I’m getting a lot of calls from Silver Springs residents who are feeling aftershocks — even up to magnitude 3,” Rowe said. “So they’re talking about what feels like persistent aftershocks when they’re getting repeated aftershocks right after the main shock.”
A woman said she was at home with her daughter when the earthquake struck.
“It was difficult to walk. I tried to go under a table while holding her. And it seemed like it was difficult to move and maneuver and we heard stuff falling,” she said. KTVN-TV. The vibration was “really nerve-wracking” and so strong that it broke his TV.
Nevada has largely escaped devastating earthquakes since the 1960s, except for one of magnitude 6. Wales earthquake of 2008Due to which an abandoned two-storey building collapsed and two more buildings partially collapsed and around 30 others were damaged in the northeastern part of the state. Authorities reported losses of $19 million.
But from 1850 to the 1950s, 22 earthquakes of magnitude 6 or greater occurred in Nevada.
In 2020, a magnitude 6.5 earthquake struck Nevada, but it was in a remote location — about 200 miles northwest of Las Vegas and 125 miles southeast of Carson City. The Nevada Highway Patrol reported damage from the earthquake along a half-mile stretch of U.S. Highway 95, where large cracks appeared. Crews made temporary quick fixes by cutting overgrown sections of the highway to reduce bumps felt by motorists.
Even a magnitude 6 or 7 earthquake very far from a city can cause damage or death. The first documented earthquake-related death in Nevada occurred in early July 2019 during one of the two powerful Ridgecrest earthquakes that shook a large portion of Southern California.
The body of 55-year-old Troy Ray was found on July 9, 2019; Apparently, he was working under his Jeep in his hometown of Pahrump, Nev., about 95 miles northeast of the earthquake’s epicenter, and was believed to have fallen on top of his vehicle.
So are the latest earthquakes in Nevada a cause for concern?
They’re actually “basically typical for Nevada earthquakes,” Rowe said. And “These Nevada earthquakes change nothing for California’s earthquake risk.”
Still, major earthquakes can strike without warning, and that’s part of the risk of living in places like California and Nevada.
Rowe said people should participate in earthquake drills like ShakeOut, which is scheduled for Oct. 15 and reminds people what to do when they feel an earthquake: drop, cover and stay.
“At 10:15 in the morning, school kids will do it,” Rowe said, “but everyone should do it.”
