Earthquakes shake Nevada more frequently

Editor’s note: This is the first of three articles from the Rural Preparedness Summit that is both educational and instructive for residents who live in an earthquake-prone state.

Rural emergency first-responders recently received a healthy dose of situations that could affect them in answering future calls.

At the fourth annual Rural Preparedness Summit held at the Fallon Convention Center, participants from most rural communities throughout Nevada learned about the advanced methods in searching for lost people to understanding the crisis standards of care and noting the updates to the Health Alert Network.

For Fallon’s first responders, though, they focused on workshops that updated them on the earthquake hazards in Nevada, search and rescue, radiation and innovations in retrofitting emergency medical vehicles.

Understanding seismic activity

Dr. Annie Kell from the University of Nevada, Reno’s Nevada Seismological Laboratory, is passionate about understanding the increasing seismic activity in the Silver State and how people can prepare themselves in case another magnitude 6.0. The Education and Outreach seismologist said Nevada is now seeing as much seismic activity as the West Coast.

Alaska experiences the most seismic activity followed by California and then Nevada, but Kell said the Silver State is gaining.

“Nevada is almost tied with California,” Kell pointed out. “Washoe County, for example, has had swarms of magnitude 3.0 and 4.0 activity.”

Kell said a regional monitoring network has been recording activity in western Nevada and eastern California and then publishes the data. Furthermore, Kell said the well-known San Andreas Fault, which is 600 miles long, experiences about 20 percent of its plate boundary motion in the Sierra Mountains and along western Nevada.

According to the data, she said Walker and Pyramid lakes and Lake Tahoe have been active as has Owens Valley south of Bishop, Calif.

“The rest of Nevada also has high amounts of motion as well,” she said.

Kell, though, informed the first responders what most Nevadans already know. The state is prone to magnitude 5.0 and 6.0 earthquakes. Fallon, she said, has an 80-90 percent probability of experiencing a magnitude 5.0 trembler sometime in the future; on the other hand, Reno, Dayton, Carson City and Incline Village at Lake Tahoe have a 90-percent probability.

Not all predictions are on the mark, though.

Kell said Wells, a small city of 1,200 people 45 miles east of Elko, had a 9 percent probability to experience a 6.0 or greater magnitude earthquake, yet that changed on Feb. 21, 2008. At 6:16 a.m. five miles northeast of Wells, a magnitude 6.0 earthquake rattled Wells, causing some storefronts that faced the railroad line to crumble. The high school gymnasium also experienced some structural damage.

The quake caused $10.5 million in damage. All 700 of the town’s residential structures experienced some kind of damage while 20 were destroyed. No one died or was seriously injured, a miracle in itself.

CLOSE TO HOME

Not only does Kell understand the complexity of how and why the earth shakes, but she also experienced a magnitude 7.0 earthquake as a graduate student in Christchurch, New Zealand in 2010.

Kell reviewed four major earthquakes that created damage and anxiety among residents in central Nevada in 1954. Two earthquakes struck during the summer, and the other two rocked the area on Dec. 16. On July 6, scientists recorded a magnitude 6.6 earthquake followed by a magnitude 6.8 quake on Aug 23. The first quake in December was the strongest of the four at magnitude 7.1 and the other at magnitude 6.8.

“These quakes did major damage to Rogers Dam, buildings, roads, irrigation facilities,” she said. “There were damaged chimneys in Fallon.”

Not only were the earthquakes felt to some degree in the adjacent states but also felt in every Nevada county.

Fallon, the town nearest the epicenter of the July earthquake, experienced severely damaged old and poorly built concrete-block structures and many brick chimneys fell. According to accounts from the military, several people were injured at the Naval Auxiliary Air Station, when the shock knocked heavy steel lockers onto them. The Lone Tree district to the south of Fallon and the Stillwater district to the east had sustained damage. Ground motion and surface breakage were heavier in Stillwater.

According to the United States Geological Survey, “Canals and drainage systems of the Newlands Reclamation Project near Fallon were damaged extensively. Many box-type culverts were damaged or collapsed. Failure of the Coleman Diversion Dam cut off irrigation water to most of the project.

“Paved highways in the Fallon-Stillwater areas settled, cracked, and buckled in several places. One of the largest ground movements occurred in the Lone Tree area. One road dropped almost 1 meter for a distance of several hundred meters and lurched about another meter horizontally toward a canal. In the Lone Tree and Stillwater areas, canal banks settled as much as 0.9 meters, and bottoms of canals were raised as much as 0.6 meters.”

The Aug. 24 earthquake resulted in a Rainbow Mountain fault that extended almost 60 feet.

The December earthquakes revealed fault displacements were along normal faults west and southeast of Dixie Valley, east of Fairview Peak and east of Stingaree Valley. “Heavy furniture was displaced at Frenchman Station, about 11 kilometers west of major surface faulting, but damage to buildings was negligible,” reported the USGS. “Differential settlement of about 10 centimeters that occurred under a wood-frame store resulted in minor cracking of the building. Damage at Fallon, about 48 kilometers west of the nearest major surface break, was limited to a few toppled chimneys. Hundreds of aftershocks occurred.”

WHEN, NOT IF

Although a major earthquake such as the ones that struck central Nevada has not occurred in decades, Kell said it’s a matter of when, not if.

“It’s been 61 years since a large magnitude earthquake occurred in our state,” she said.

Kell, though, bristles when people tell her Nevada doesn’t have the “big earthquake.” On the contrary, Kell said Nevada has had its share of the big earthquakes, many of them occurring since 1912 when a magnitude 7.0 quake shook Paradise Valley north of Winnemucca.

Kell reminded attendees about being prepared when the big earthquake strikes. She said a survival kit should contain enough food and water for three days. The kit should also have a family plan, medical supplies, pet food and a power supply.

The same technique for individuals to follow has not changed over the generations. She said people seek a sturdy object to get under and then “drop, cover and hold.”

“Quickly down as quickly as possible,” she said. “Protect your head and neck.”

After a big earthquake rattle the area, Kell said people should expect aftershocks and not depend on emergency responders because they may be busy elsewhere.

NEXT: Search and rescue operations rely more on technology.