Here’s Where Earthquakes Have Happened in Southern Utah

There is a fault that runs from the end of the Cedar Valley, down past Toquerville and Hurricane, across the Grand Canyon and all the way to just east of Kingman Arizona. It is known as the Hurricane Fault and is capable of delivering a 7.0 earthquake. In 1992 this fault moved causing a 5.8 temblor known as the St. George earthquake. 

So, what are the chances of it shaking again in the near future? The US Geological Survey notes that the fault has been active for a very long time, and therefore, will likely continue to be. 

Complex geology and variable topography along the 250-kilometer-long Hurricane fault in northwestern Arizona and southwestern Utah combine to create natural conditions that can present a potential danger to life and property.   

Some of those potential dangers are of course the shaking of buildings and houses, but it could also block streams and rivers causing possible flooding. The fault also shows a long history of landslides. This could cause damage to roads and structures close by. 

This information from a website about Silver Reef gives a good idea how active the fault has been. By looking at the disruption to ancient lava flows on the ridge, they can get an idea. 

Knowing how much the rocks are offset by faulting (1200 feet) and knowing the age of the flow (850,000 years old), it is a simple matter to calculate a long-term average rate of displacement on the fault of nearly two feet per thousand years. 

If those calculations are correct, we shouldn’t see too much shaking in Southern Utah any time soon. Of course, nothing is for sure and it doesn't hurt to be prepared.