Magna earthquake helps scientists understand Utah’s vulnerability
Mar 18, 2022, 12:34 PM | Updated: 3:27 pm
SALT LAKE CITY — The earthquake centered near Magna on March 18, 2020, damaged buildings in nearby cities and caused some injuries, but no deaths. For scientists, though, the quake has helped them learn much more about the Wasatch Fault system that underlies many of the most populated areas of Utah.
Among the most significant lessons of the quake, said University of Utah Research Scientist Katherine Whidden, was that the quake occurred on a segment of the Wasatch Fault.
“Before this, we thought that the Wasatch Fault only produced magnitude 7 earthquakes,” Whidden told KSL Newsradio. “So this was interesting to see that it can produce smaller earthquakes. Magna was a 5.7.”
“It’s not a surprise that we could have damage from a five-and-a-half or that a five-and-a-half happened here, but the interesting part is that it happened on the Wasatch Fault itself,” Whidden said.
Much of what they’ve been able to learn is the result of the ongoing series of aftershocks that have happened since the Magna earthquake. There have been more than 2,600 aftershocks, most of them too small to feel. Only six were magnitude 4.0 or larger.
Seismologists placed dozens of sensors in the area east of the Kennecott tailings pond, where the quake was centered and used the data from the smaller shocks to add to their knowledge of the event. In one published study, the team said they had to hold off placing sensors for a day or two because fresh cougar tracks had been discovered in the area.