Earthquake shakes Silver Valley

MULLAN — Folks settling in for the evening Monday got quite the shock when an earthquake briefly rattled through the area.

According to the United States Geological Survey, the epicenter of the 3.3-magnitude quake was a little under 2 miles north of Mullan, but people from as far away as the Kingston/Cataldo area reported feeling something.  

Monday’s earthquake was measured at a depth of 3 miles, which classifies it as a shallow-focus earthquake. Shallow-focus earthquakes are more destructive than their deeper counterparts because they release more energy.  

Shoshone County is no stranger to geological activity, with several significant faults coursing through the area, but it was the first quake of its size in almost three years.  

According to Steve Sobieszczyk with USGS, there have been five earthquakes with an M3 or greater in the Mullan area since 2000, including an M3 that occurred May 22, 2022.  

Idaho in general is a geological hotbed due to its proximity to an area known by geologists as the Basin and Range Province. Consequently, hundreds of geological faults are created due to the seismic activity in this region. In the Silver Valley, the Osburn Fault runs the length of the county and is prone to seismic activity.   

According to USGS’s catalogued records, which date back to just 1985, the largest earthquake within the area most recently happened Dec. 22, 1998, when an M4.7 rattled the Idaho/Montana border. 

In March 2020, North Idaho experienced a hefty aftershock from an M6.5 quake that originated outside Challis. People in grocery stores reported items falling from shelves.

The 1983 Borah Peak earthquake, Idaho’s strongest, was a magnitude 6.9, and resulted in the deaths of two people in Challis near the earthquake’s epicenter.