STORY AND PHOTO BY KAREN BOSSICK

There’s a whole lot of shaking going on in Stanley.

More than a hundred small earthquakes have occurred in the past couple of weeks 10 miles east of the Sawtooth Fault, an old fault that runs 40 miles across central Idaho. And scientists are noting some unusual things about the swarm.

The activity has revealed a fault that geologists did not know existed, Lee Liberty at Boise State University’s Department of Geosciences told KTVB.

And the mini quakes are unusual in that they’re moving side to side, rather than up and down, as most Idaho earthquakes do.

Most of the quakes have been between 2.0 and 3.5 in magnitude but several have reached 4.0. Experts say damage does not usually occur until the magnitude is in excess of 4.0 or 5.0, the damage depending on such variables as distance from an earthquake, the soil in the area and building construction.

The swarm is occurring along the same fault that was implicated in Idaho’s 6.5 magnitude earthquake in March 2020.

That quake rattled people as far away as Boise and Twin Falls in March 2020 while everyone was sheltering in place during COVID.

It broke off one of the fingers of Finger of Fate and damaged the nearby Arrowhead rock formation. And the sandy beach at Stanley Lake’s inlet collapsed, lost forever.

The 6.9 magnitude Borah Peak earthquake in 1983—Idaho’s largest ever--raised Mt. Borah a foot and collapsed a building in Challis that killed two schoolchildren walking to school.

Aftershocks from both of those quakes continue to this day.

Ground liquefication, in which water-saturated sediments become weakened and flow like liquid could be taking on the appearance of high-pressure fluids that are weakening the fault zone and causing it to slip, generating the ongoing swarm, said James Thompson, of Modern Engineering Marvels.

Scientists don’t know how long this will go on, nor do they know if they portend a stronger quake. But, at present, they don’t seem concerned.

So don’t cancel your reservations to Redfish Lake.

That said, Idaho ranks fifth in the nation for earthquake risk. And the Sawtooth Fault is capable of producing earthquakes of magnitude 7 or greater, which could leave people quaking in their boots hundreds of miles away.

Prehistoric faults in the area took place 4,300, 5,100, 7,600 and 9,000 years ago, according to Thompson.