A sizable aftershock jolted the Salt Lake Valley on Tuesday night, reigniting jitters for residents hit by a much stronger earthquake less than a month ago.
The magnitude 4.2 quake, centered 2.5 miles northeast of Magna, struck at 8:56 p.m., according to the U.S. Geological Survey. It was later downgraded to magnitude 4.17.
There were no immediate reports of damage.
The latest temblor was among the most powerful aftershocks since March 18, the day a magnitude 5.7 earthquake rocked northern Utah, damaging more than a hundred historic buildings, a number of schools and dozens of homes. No one was killed or seriously injured.
Still, hundreds of aftershocks since then have shaken — physically and emotionally — hundreds of thousands of people.
“This aftershock is part of the Magna sequence,” the University of Utah Seismograph Stations tweeted Tuesday night, “and even though we have not felt shaking for a couple of weeks, the aftershocks are ongoing and this is normal.”
Normal but hardly soothing for a crisis-weary populace already grappling with stay-at-home directives due to the coronavirus pandemic.
“I call them coronaquakes," Holladay resident John E. Henderson wrote on Facebook. "Can’t go outside, can’t stay inside.”
Tuesday night’s shaking — the strongest since the day of that mainshock — was felt in Salt Lake and Davis counties, including in Magna, West Valley City, South Jordan, Sandy, Salt Lake City, Bountiful and Farmington.
“It was mesmerizing watching my clothes jiggle in my closet,” tweeted Nicole Bullock from West Jordan.
“Just today I was thinking, ‘at least I don’t have to worry about earthquakes anymore,'” tweeted environmental activist Deeda Seed, a former Salt Lake City councilwoman.
“Slow-motion and panic," Murray resident Jenny Noonan Dye wrote on Facebook. "The 11-year-old was about to get in the shower. We called her back downstairs (and of course by that time it was over).”
It was the 629th aftershock exceeding magnitude 1 since the mainshock, according to the USGS, and the fifth exceeding magnitude 4. On March 22, a magnitude 3.94 quake, initially pegged at magnitude 4, also jostled the Salt Lake Valley.
Most of the aftershocks were centered near Magna, although some weaker quakes occurred several miles to the east, under Salt Lake City.
Late Tuesday, the U. Seismograph Stations pointed to 1,247 aftershocks from the March 18 quake. “The aftershock activity is expected to continue for at least several more weeks,” the U. said in a news release, “but with the rate continuing to decrease with time.”
— Tribune reporter Brian Maffly contributed to this story.