Two earthquakes struck Nevada within seconds of one another Friday, shaking a part of the western United States where the Earth’s crust is gradually pulling apart.
The US Geological Survey recorded the tremors at magnitudes 3.6 and 3.5 near Preston, a community with more than 160,000 residents.
According to Michigan Technological University, earthquakes measuring between 2.5 and 5.4 are commonly felt but generally cause little or no damage.
No damage had been reported following Friday’s activity.
The stronger earthquake occurred at 10:10 a.m. ET, followed 24 seconds later by the second tremor near Preston. The community lies within the Basin and Range Province, an expansive region covering much of the western United States.
The area is undergoing a slow process of stretching and thinning as the Earth’s crust pulls apart, creating conditions that produce frequent faults and earthquakes.
When the crust fractures, faults develop. Earthquakes occur when blocks of rock shift along those breaks.
Friday’s quakes were relatively weak, but seismic activity across the Basin and Range Province reflects the forces that continue to split, stretch and reshape the landscape.
A magnitude 6.5 earthquake hit Nevada in 2020 (pictured), likely as a result of cracking and stretching across the Basin and Range Province
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The Basin and Range Province covers more than 300,000 square miles, extending across most of Nevada, Utah, eastern California, southern Idaho and Oregon, as well as parts of Arizona and New Mexico.
As the crust stretches across the province, it fractures into enormous blocks.
Some blocks drop downward to create valleys, while others stay elevated or tilt to form mountain ranges.
Over millions of years, this geological stretching has broadened the region and left the crust beneath it thinner.
Friday’s activity came after a series of earthquakes near Preston in recent months, including two magnitude 4.1 tremors west of the community on September 27.
The USGS ShakeMap indicated that the strongest shaking was concentrated near Friday’s epicenter and weakened with distance.
Trina Thomasson wrote on Facebook that she felt the shaking in Ely, roughly 32 miles northeast of Preston.
Nevada is the third-most seismically active state in the country, behind Alaska and California, according to the Nevada Bureau of Mines and Geology.
Earthquakes occur somewhere in the state every day, most of them too small to cause significant effects.
However, Nevada has also endured earthquakes powerful enough to permanently transform the landscape.
On December 16, 1954, a magnitude 7.1 earthquake struck Fairview Peak in central Nevada. About four minutes later, another major earthquake hit nearby Dixie Valley.
The pair of earthquakes caused ground movement along several faults, with vertical displacement reaching about 12 feet in some locations.
They also set off landslides and rockfalls and altered the flow of springs and wells.
Even so, a sequence of smaller earthquakes does not automatically mean a major earthquake is imminent.
The USGS notes that some earthquake clusters end without a larger shock. Scientists can identify a tremor as a foreshock only after a more powerful earthquake occurs.