Researchers studying Taylorsville-West Valley City Fault to better understand quake conditions in Utah

Posted at 10:04 PM, Sep 05, 2015
and last updated 2015-09-06 00:04:50-04

TAYLORSVILLE, Utah -- A research team is digging up a portion of the Taylorsville-West Valley City Fault out by the Salt Lake City International Airport, and their goal is to get a better sense of the danger from that fault and how big of an earthquake it could create.

The group’s findings could impact future developments all across Utah, as scientists are measuring a section of the Taylorsville-West Valley City Fault, tracking earthquakes from before Utah was settled.

“When these kinds of faults have ruptured the ground surface, it’s been at least a magnitude 6.5,” said Mike Hylland of the Utah Geological Survey.

The researchers are working to figure out how often that fault experiences an earthquake, though they said the bigger danger lies just to the east on the Wasatch Fault.

“Things are moving apart,” said Chris Duross, a research geologist for the United States Geological Survey. “Reno is moving apart from Salt Lake City very slowly, and the Wasatch Fault allows that extension to occur.”

The geological evidence shows the Wasatch Fault triggers an earthquake every 1,000 to 1,500 years.

In some places it’s been more than 1,000 years since the last earthquake, and two of Utah’s most densely populated areas could be the most at-risk.

“Salt Lake City and Provo, they sit in valleys with mountains on either side, and these valleys can trap ground motions and seismic energy,” Duross said.

The geologist said it’s not a reason to panic, but rather a good reason to plan.

“Large earthquakes can occur in this region,” Duross said.

Their results could impact future building codes, creating safer buildings when the tension on the fault line finally reaches a breaking point.

“You can think of it like a rubber band,” Duross said. “So you’re slowly pulling a rubber band and eventually that rubber band is going to break.”

One focus of the current research is to figure out if the Taylorsville-West Valley City Fault generates its own earthquakes, or if it shifts along with the larger Wasatch Fault.