Two earthquakes struck Nevada within seconds of each other on Friday, shaking a region of the United States where the Earth’s crust is slowly pulling apart, the Daily Mail reported.
The tremors measured magnitudes of 3.6 and 3.5, striking near Preston, an area home to more than 160,000 people. The United States Geological Survey recorded the largest earthquake at 10:10 a.m. ET, with the second striking just 24 seconds later outside the community.
Michigan Tech University assessments show that earthquakes ranging from 2.5 to 5.4 in magnitude are often felt by residents but typically cause only minor damage. No damage from Friday’s seismic activity has been reported by authorities.
Preston sits within the Basin and Range Province, a vast region spanning more than 300,000 square miles across much of Nevada, Utah, eastern California, southern Idaho, Oregon, Arizona, and New Mexico. In this area, the Earth’s crust is gradually stretching and thinning, creating frequent faulting and seismic activity.
“I felt shaking in Ely,” Trina Thomasson posted on Facebook, describing tremors felt about 32 miles northeast of Preston.
Recent months have seen multiple seismic events near Preston prior to Friday’s shocks, such as a pair of 4.1-magnitude tremors registered west of the settlement on September 27. The USGS ShakeMap showed estimated shaking concentrated around the epicenter on Friday, fading farther from the source.
As the Earth’s crust pulls apart in the Basin and Range Province, it breaks into massive blocks. Some sink to form valleys, while others remain higher or tilt to form mountain ranges.
Through the course of millions of years, this extension has substantially broadened the territory and substantially reduced the thickness of the underground crust. While Friday’s earthquakes were minor, seismic activity along the province contributes to the ongoing splitting, stretching, and reshaping of the area. A 6.5-magnitude earthquake struck Nevada in 2020, likely caused by the Basin and Ridge Province cracking and stretching.
Nevada ranks as the third most seismically active state in the United States, trailing only Alaska and California, according to the Nevada Bureau of Mines and Geology. Small earthquakes occur somewhere in the state every day.
The state has also experienced earthquakes powerful enough to permanently reshape the ground. Central Nevada’s Fairview Peak was hit by a magnitude 7.1 earthquake on December 16, 1954, and roughly four minutes later, another major earthquake rattled nearby Dixie Valley.
Those historical earthquakes shifted the ground along multiple faults, with vertical movement reaching about 12 feet in places. They also triggered landslides and rockfalls while changing the flow of springs and wells.
However, the USGS notes that a series of smaller earthquakes does not necessarily mean a major one is approaching. Certain groups of tremors dissipate without a subsequent major shock, meaning researchers can only recognize a foreshock after a larger earthquake has already occurred.
